Posted by: glamielle | May 3, 2012

Bovine Spongiform Encephalopathy (Mad Cow Disease) detected in Central California, USA

usda.gov

Last week (April 24th, 2012), a case of Bovine Spongiform Encephalopathy (BSE) was identified in a single animal in Central California.  This case, recorded in a dairy cow, is the 4th ever case in the USA and was discovered through the USDA’s BSE Surveillance Program, which is a very stringent system allowing officials to detect the disease at very low levels. The USDA is still investigating the case but the appropriate measures have already been taken, and the affected animal did not enter the human food chain, therefore preventing any spread to people. Furthermore, the affected cow’s progeny has been tracked down and is currently being tested for the disease and the dairy farm where the animal originated is under quarantine. The Department further emphasized that beef is still safe to consume.

The disease, commonly known as Mad Cow, is caused by abnormal molecules called prions that, once ingested, travel to the animals’ brains causing degenerative changes leading to neurologic signs such as tremors, incoordination or seizures. The disease is not infectious and does not transmit from a live animal to another animal. However, transmission can occur through ingestion of parts of affected animal that contain the prion, such as the brain or spinal cord tissue. This is why BSE has traditionally been associated with a practice consisting of feeding beef-based diets to cows, in order to promote protein intake. This practice is, however, illegal now in most countries, including the US and that has led to a decrease in BSE worldwide.

BSE causes degenerative changes in the patient’s brain, characterized by vacuole formation (http://www.sciencedaily.com)

Transmissible spongiform encephalopathies can nevertheless appear spontaneously in some animals, although very rarely, and it appears that this is what happened in this case. Similar diseases exist in other animal species such as Scrapie in sheep or Chronic Wasting Disease (CWD) in wild deer. Whether or not these diseases can be transmitted to humans remain unclear.

People eating beef containing nervous tissues (brains, spinal cord) of a cow with BSE can a disease called variant Creutzfeldt-Jakob Disease (vCJD) and is closely related to the human-only disease Creutzfeldt-Jakob Disease (CJD). Symptoms of vCJD are very similar to those of BSE in cows and can include tremors, confusion, dementia or difficulty walking. There is unfortunately no treatment or cure for the disease and one of the challenges (in both animals and people) is that the incubation period (amount of time until symptoms appear after exposure) can be very long and it can take decades for the disease to manifest itself.

This case was very promptly detected by the USDA during routine testing and shows the importance of continued disease monitoring like BSE. Although very rare however, they can cause significant public health problems and also critically injure a country’s agriculture. Sometimes, the public opinion is to cut resources for disease monitoring programs that have not detected any disease for some time. However, the fact that such programs do not observe any positive does not reflect failure or lack of usefulness. On the contrary, if we stop looking for these diseases we might miss the next epidemic.

Michael Alpers presenting the movie “Kuru – Science and Sorcery” at the One Health Congress in Melbourne, Australia about his pioneer work leading to the discovery of prion diseases

More information:

CDC – Bovine spongiform encephalopathy

FDA – All about BSE

OIE – Number of BSE cases reported worldwide

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Posted in Food safety & security, USA, Zoonoses

Posted by: glamielle | January 12, 2012

Rabies, one of the most well known zoonoses remains a significant public health issue worldwide

Hello everyone, I would first like to wish to all of you a great and prosperous year 2012 and I would like to thank all of those who have visited the website as well as supported me and left comments.

I want to start the year talking about one of the most recognized zoonotic diseases in the world: rabies. However, in spite of its somewhat “famous” status, I have observed that some people miss some key facts regarding this disease

As a small animal practitioner, rabies prevention through pet vaccination is a cornerstone of my work and I always take the time to educate clients about the risks posed by the disease, but also proper management of animals to reduce likelihood of transmission to animals and people. As such, I have noticed some discrepancies between what people know about rabies and what I believe are other important points.

Rabies is caused by a virus from the Rhabdoviridae family and it is present generally worldwide except some parts of the world such as Hawaii or New Zealand. Several European countries have also become rabies-free after intensive wildlife vaccination programs.

The Common Vampire Bat is a species of bat often implicated in rabies transmission to livestock in Latin America. (wikipedia.org)

One of the greatest misconceptions comes from the belief that it only affects dogs. However, the virus can be found in virtually every mammal, including dogs, cats, bats, cows, horses, sheep and several wildlife species. In fact, there have been several outbreaks of rabies in livestock recently in cows in Costa Rica and Peru in November and December 2011 as well as in a horse in Colorado in April 2010. Transmission is done by a bite of from an infected animal, when virus particles are inoculated into the muscle of another animal, or human.

Once the virus enters the hosts, it replicates in the muscle and travels to the brain inside neurons. Animals and people affected with rabies can usually show a wide range of neurologic clinical signs such as pain, difficulty walking, lack of coordination, or aggression. Some animals, however, can also exhibit what is known as “dumb rabies”, showing signs of depression and lethargy. The disease is progressive in nature and as more organs become affected, patients can also exhibit difficulty swallowing (commonly recognized as fear of water) and sensitivity to light. Patients eventually die from asphyxiation as their respiratory muscles stop working. Clinical signs in animals in people can appear between 10 days to several months after being bitten.

Pets can be exposed to rabies when they come into contact with wild animals such as this skunk. (http://www.globalanimal.org)

There is virtually no treatment against rabies, and affected animals are usually required to be euthanized to protect human health as  well as prevent unnecessary suffering of the patient. Treatment options in people who have been bitten by an unvaccinated animal are also scarce, usually limited to post-exposure prophylaxis (PEP). Essentially, PEP is injection of hyper-immune serum into the wound of an infected person to prevent further virus replication. For this to work, timing is critical and once the virus has entered the nerves, PEP will be of little use. This is why those who have been bitten must go to the hospital as soon as possible to receive PEP treatment. Once people start exhibiting symptoms, prognosis is very poor and these individuals will unfortunately most likely die. There has been a newly developed treatment protocol known as the Milwaukee Protocol that has had some success in treating and curing a handful of people showing symptoms of rabies. This treatment is, however, very challenging and requires the affected person to be put in a coma for a long time. There has been to date only 6 people who have survived rabies using this or similar protocol and if we compare with the number of infected people in the world (about 50 000), the mortality rate for rabies remains approximately 100%.

Rabies has been known for hundreds of years and was one of the first diseases to which a vaccine was created in the 1800s by Louis Pasteur. However, the virus remains prevalent worldwide and affects about 50 000 people yearly. As with many zoonotic diseases, the developing world can be more severely affected and some risk factors for rabies in animals and people include: large population of stray dogs and cats, dog fighting, or close contact between humans and wildlife.

However, rabies can also cause problems in developed countries. An article published in the Journal of the American Veterinary Medical Association (JAVMA) compiled all rabies cases (human and animals) for the year 2010 in the USA. Rabies in pets is usually well controlled in this country, however, several other species of animals can host the disease in the wild, depending on geographical location. The East Coast of the US is characterized by raccoon hosts while on the West Coast, skunks predominate. In other parts of the countries, foxes are also known to harbor the disease. During the year 2010, there has been several reported cases of rabies in domestic animals: 303 cats, 71 cattle, 69 dogs, 37 horses and 6 goats/sheep. Looking at these numbers, it is obvious that the major misconception that dogs only can be affected by the disease doesn’t hold as canine cases come in third place after cats and cattle. It is also important to remember that all these animals are potentially sources of the disease in people. Reported cases in wildlife included raccoons (2246), skunks (1448), bats (1430), foxes (429) and rodents/rabbits (33). These numbers represent the reported cases, meaning that these animals were submitted to laboratory for testing, thus it is likely that the actual numbers were higher. Finally, there have been 2 cases of human rabies during 2010, both fatal. One case was seen in a migrant worker in Louisiana who had been bitten by a vampire bat in Mexico about 10 days before showing symptoms of rabies. The second case was a man in Wisconsin who was hospitalized with difficulty swallowing. Viral testing revealed a strain commonly seen in bats of the area.

Distribution of wildlife terrestrial hosts of rabies. Bats are not terrestrial animals and are not depicted on this map. (http://www.cdc.gov)

It is important to notice that both of these people were infected after being bitten by bats, thus showing how important this species is when it comes to zoonotic transmission of rabies. In fact, the latest case of rabies in the US was seen in Massachusetts over the end of December 2011. The patient started exhibiting neurologic signs after having been bitten by a bat (once again) and is currently (as of January 2012 when this post was written) hospitalized in critical condition. This is the first case of human rabies in Massachusetts in over 70 years. These cases remind us that, while in many parts of the US, canine rabies cases have gone down, bats are often the most important vector for human rabies.

Considering the severity of the disease, there are several guidelines that people should follow to reduce their likelihood of infection. One of the most important is to stay away from wildlife, especially those animals that are exhibiting strange behavior including aggression or absence of fear. As previously mentioned, bats play a very important role in transmission of rabies and should not be handled by people who are not qualified. Animal control authorities should be called if someone notices a bat in their house. These animals  have small sharp needle-like teeth so bites can often go unnoticed.

There are good vaccines available against rabies, both in animals and people, and those in close contact with animals should definitely be up to date on rabies vaccination. These include people working in veterinary clinics, animal shelters and, in my opinion, livestock workers as well. Likewise, all cats and dogs should be current on their vaccines. Some cat owners may feel that their indoor cat is not at risk of contracting rabies compared to animals that go outside regularly. While that may be true, the severity of the disease warrants strong preventive measures to be put in place in order to protect pets and animal owners alike. In some instances indoor cats may find their way outdoors accidentally and become exposed to rabies. Also, it is not uncommon for bats to be able to enter homes and cats can be attracted by a bat struggling on the floor of a home.

Unvaccinated animals biting people or other pets must be put under strict quarantine or euthanized. (http://www.ccac.ca)

In fact, the diagnosis of rabies in animals usually involves some significantly drastic measures and the issue arises if an unvaccinated  pet/animal bites a person. Laws of different cities/countries may differ on the subject, however, they do follow the same general guidelines. If an unvaccinated animal bites a person, that pet may be required to be put in quarantine at the owner’s expense or even be euthanized in order to submit the brain for laboratory analysis. Maintaining appropriate vaccination status in pets is an easy and simple way to prevent such measures to be taken to protect the public.

In many countries, especially in the developing world, rabies is maintained by stray dogs and cat populations. It is therefore also important to take steps to reduce stray animal numbers and spaying/neutering pets is a great way to achieve that.

Finally, just as in any public health issue, population education is essential to ensure that the public is aware of the risks caused by rabies and the steps they can take to reduce the incidence of the disease in both animals and people.

Dog vaccination programs help greatly in managing rabies incidence in developing countries. (http://www.rabiescontrol.net)

For more information on rabies:

World Health Organization – Rabies

Centers for Disease Control and Prevention – Rabies

Los Angeles County Veterinary Public Health – Rabies control manual

Rabinowitz PM & Conti LA. 2010. Human-Animal Medicine. Saunders Elseviers ed.

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Posted in All posts, USA, Wildlife, Zoonoses

Posted by: glamielle | November 25, 2011

The pet veterinarian as a public health advocate

The role of the veterinarian in promoting public health does not always involve work in developing countries or tropical places. Zoonotic diseases, or diseases common between animals and people, are present worldwide, including in the homes of pet owners.

It is clear that the importance of pets in today’s households is significant, and it is thus crucial for animal owners and physicians to take into account the pet when looking at disease dynamics in a family. Indeed, pets can serve as a source of infection to people, and vice versa, and the close contact that many have with their companion animals puts them at higher risk of infection from these pathogens. This is why the veterinarian should be an active member of a family’s health team and work together with family physicians when evaluating how the pets’ health can affect households.

In order to assess this risk of transmission of zoonosis from pets to humans, it is important to focus our attention on several groups who are at higher risk of infection. These usually include children, the elderly, pregnant women or those with depressed immune systems like those individuals with HIV, cancer or other chronic conditions.

Due to close contact with their pets, children are at higher risk of contracting diseases from companion animals. (http://leerburg.com/308.htm)

This does not mean that people should refrain from having pets and, if the animals are treated properly, the benefits of having a pet definitely outweigh the risks. What needs to be done is to realize that these animals should be maintained healthy in order to reduce likelihood of transmission of disease to people.

More than half of infectious diseases in people are shared with animals, including some of the more famous diseases like rabies, plague or influenza. However, there are more pathogens that pets can harbor and can infect people.

Roundworms & hookworms

Roundworms, specifically by Toxacara canis and Toxacara cati, are nematodes of the dog and cat that are commonly affect veterinary patients. Often seen in younger animals, toxacariasis is transmitted by ingestion of eggs from the environment or from contaminated

Child affected with ocular larva migrans from Toxacara infection (sunnysidevet.net)

meat, although nursing puppies an also acquire the parasite from the milk of an infected female. The disease in animals is usually mild and is characterized by gastrointestinal inflammation, distended abdomen and lack of weight gain. In some severe cases, worms migrating from the intestinal tracks to other organs such as liver or lungs can cause a more severe clinical appearance such as respiratory disease. Humans also get infected from ingestion of eggs from contaminated soil, or sometimes on animal’s fur. The parasite can also be present in larval form in tissues of a wide range of species such as cattle or birds, and as such, eating infected meat represents another transmission pathway. The disease in people is represented by two major processes: ocular-larva migrans and visceral-larva migrans. In ocular-larva migrans, parasites migrate to the eyes of the affected person, where they can generate strong inflammatory response. Visceral-larva migrans is characterized by larval migration to internal organs, where the parasite can become dormant. This disease is usually mild although inflammatory response can rarely lead to severe symptoms. In both of these syndromes, children are at higher risk of infection due to their close contact with dogs and cats as well as potentially contaminated soil or sand.

Cutaneous larva migrans from Ancylostoma infection. (ruby.fgcu.edu/courses/davidb/50249/web/clm1.htm)

Hookworms are also a common occurrence in veterinary patients. Caused by Ancylostoma or Uncinaria species, these infect dogs and cats, especially kittens and puppies as well as stray animals. Infected hosts shed eggs into the environment and the parasite needs to hatch and develop into a larva before becoming infective to other species. Disease in dogs and cats is usually mild and characterized by weight-loss and diarrhea however, severe infection can lead to anemia. One important characteristic of hookworms is that the larvae living in the environment have the ability to directly enter the skin or mucous membranes of hosts, which is how humans most commonly get infected. People walking barefoot outdoors can have hookworm larvae enter through the skin, causing intensely itchy and inflammed lesions where the parasite is seen migrating under the skin. Rarely, hookworms in people can cause pulmonary and gastrointestinal symptoms.

While hookworms and roundworms are some of the most common parasitic zoonoses of pets, it is important to remember that other parasites of dogs and cats can be transmitted to people, such as tapeworms (Dyplidium sp.) and whipworms (Trichuris sp.). In all these cases, frequent deworming of dogs and cats leads to a decreased chance of infection in people

Giardia

Giardia lamblia are unicellular protozoans that are present in both animals and people. Commonly found in the intestinal tract of many animal species including wildlife, the parasites are shed in the feces and can survive well in water sources. Clinical appearance in both animals and humans is similar, commonly showing gastrointestinal involvement. Dogs and cats most often have watery diarrhea that may be bloody, depending on the severity of the infection. Vomiting, lethargy and decreased appetite can also be present. Diagnostics is usually done through evaluation of a fecal sample by identifying the parasite its cyst form directly under the microscope, although other tests like ELISA can detect the microbe more efficiently. Humans show very similar symptoms, including diarrhea and abdominal pain. Treatment in both animals and people include medicating with drugs such as metronidazole or fenbendazole. In my experience, giardiasis in animals can be challenging to treat and using a single drug may not do the trick. The current recommended treatment includes using metronidazole and fenbendazole together for better control.

Stained Giardia protozoans in their trophozoite forms (cdc.gov)

It is important to recognize that, both in animals and people, the parasite can be present in asymptomatic individuals, which suggests that it is part of the natural flora. This means that those who show significant disease from an infection may be more sensitive to it, such as kids (and puppies) or the immune-compromised.

Finally, while Giardia is one of the most commonly recognized zoonotic diseases from pets, it is important to realize that, in practice, it may not be the most important. There are in fact several different strains of Giardia lamblia, and each strain commonly affects a specific host. For example, Giardia types C and D only infect dogs, while type F only infects cats – human infection from these strains is not likely to cause disease in people, who are usually colonized by type A2. Some strains, however can infect a wide range of species, including people, and those are the ones that have zoonotic potential.

Giardia Assemblages A1 and B are the only ones capable of zoonotic infection (Weese JS & Fulford MB. 2011).

Toxoplasma

Toxoplasmosis, caused by protozoan Toxoplasma gondii, is mainly a parasite of cats, however the it can be found in several other animal species and humans. The disease is generally mild in both animals and people and usually goes unnoticed in healthy individuals. As such, there can be a significant proportion of the population that has had previous infection and is therefore protected, as evidenced by their elevated blood antibodies to the protozoan. Cats are the primary reservoir for T. gondii and acquire the infection from feeding on raw diets or other animals such as rodents. In felids that are infected for the first time, a large number of oocysts can be shed in the environment and thus infect other animals and people if ingested. It is important to recognize that these oocysts take 1-5 days before being infective to other species but can survive in the environment, including water sources, for long periods of time.

Disease in both healthy cats and humans usually provides good lifelong immunity to further infection, however some cats can have short-lived diarrhea diarrhea and symptoms in people are usually non-specific including headache, fever and swollen lymph nodes. While infection in healthy individuals is generally asymptomatic, the issue with T. gondi arises when it is found in special populations, specifically pregnant women and the immune suppressed, where it can cause severe illness. Toxoplasmosis is a well-recognized disease that can affect foetal development leading to abortion and neonatal death, as well as neurologic signs later on in life such as blindness, deafness or mental retardation. While previous infection in women usually generates appropriate life-long protection against the disease, a previously uninfected pregnant woman will not be able to generate sufficient immunity to prevent toxoplasmosis in the foetus.

Life cycle of Toxoplasma (http://dpd.cdc.gov/dpdx/html/Toxoplasmosis.htm)

Likewise, the parasite can cause significant disease in those with depressed immune systems in people suffering from AIDS or undergoing chemotherapy, leading to symptoms such as encephalitis. Another important aspect of toxoplasmosis infection is the potential for latency, meaning that the parasite will become inactivated in organs of healthy individuals and remain embedded for the rest of their lives. Previously healthy people who become immunosuppressed can thus suffer from symptomatic toxoplasmosis from re-activation of these hidden cysts without the need for new exposure to the parasite.

Due to the possibility of severe disease in the population at-risk, some clinicians advocate for complete removal of cats in households of pregnant women or HIV-positive patients. This drastic measure can, however, be avoided by proper management of the pet cat as well as good hygiene. Proper hygiene habits are always mandated when dealing with animals, including pets, and frequent handwashing or avoiding contact with cat feces (especially 1-5 days old), but also dirt or sand, is essential. People at risk should refrain from handling cat feces if possible, however, if they are unable to do so, the use of gloves is definitely warranted, as well as washing litter box and utensils with warm water. Reflecting the situation in humans, immunosuppressed cats are at higher risk of disease, leading to longer oocyst shedding time, and maintaining a healthy pet is an integral part of disease management in people. Cats usually have a good habit of grooming themselves however, in unthrifty or ill animals, grooming may be reduced and the cats may carry more Toxoplasma oocysts on their fur. Keeping cats indoor is also a very good way to prevent infection, as they will not be exposed to rodents that may carry the protozoan. Since it takes a few days for the oocyst in cat feces to become infective, frequent, daily cleaning of the litter box is a very effective way to prevent human infection. Finally, it is interesting to notice that, although cat ownership has increased in the US, the incidence of toxoplasmosis as been decreasing.

Ringworm

Ringworm (Microsporum canis) infection in a person. (dermnetnz.org)

Ringworm, or dermatophytosis, is one of the most common zoonotic diseases that affects a wide range of animals, especially cats, as well as people. It is caused by a group of fungus that can be found on the skin of many pets and can be spread to other individuals through direct contact, such as petting, but also fomites (couch, bedding) and fleas. Animals usually have a mild localized skin infection characterized by an area of hair loss and skin inflammation that may or may not be itchy. Likewise, in people, ringworm is characterized by circular skin lesions and is not usually severe if the individual’s immune system is working normally. Children tend to be at higher risk of infection due to their closer contact with pets. Not all cases of human ringworm are caused by a zoonotic species of fungus and it is important that physicians dealing with dermatophytosis infection in a family recommend veterinary examination of the pets to help control the outbreak.

About half of ringworm infections can glow under ultraviolet light (http://www.monvt.eu/)

Salmonella

Gram-negative staining of Salmonella sp. (textbookofbacteriology.net)

Salmonella are bacteria that are part of the intestinal flora of a wide range of animal species, especially cattle, and are mostly known as a food-borne pathogen. Symptoms in humans include diarrhea that can sometimes be severe and life-threatening. When it comes to pets, the traditional hosts of Salmonella include reptiles and birds and it is very important that people, and especially children, wash their hands after handling these animals. The bacteria are not common natural flora of dogs and cats and infection in these species usually doesn’t last more than a few weeks. In severe cases, gastrointestinal signs may occur. Therefore, the risk of transmission of Salmonella from dogs and cats to people is very low. This risk, however, can greatly increase in dogs and cats that are fed raw diets. I have seen from personal experience in the clinic that a significant number of people prefer to feed their pets raw diets. It is important to educate animal owners that these diets are usually not processed to the extent of other available pet foods and thus, contamination with bacteria such as Salmonella and E. coli will be transmitted to the pet. In fact, a study from 2008 has shown that dogs fed raw diet are 23 times more likely to shed Salmonella in their feces compared to dogs fed processed food, thus increasing chances of infecting people.  This is why it is generally contraindicated to feed such diets, especially in households where there are people at higher risk of infection such as children or immunocompromised individuals.

Methicillin-resistant Staphylococcus aureus (MRSA)

Culture and antibiotics sensitivity testing is used to determine resistance in bacteria. Each dot represents a different antibiotic used; the clear area around each dot represents the degree of sensitivity to that specific antibiotic. (http://www.staph-infection-resources.com)

The rise of antibiotic-resistant bacteria has become an important issue in both human and veterinary medicine. Specifically, MRSA is a growing issue in human healthcare contexts such as hospitals. There are two recognized forms of MRSA infection in people: hospital-associated and community-associated. Staphylococcus aureus can be a common bacteria living in the upper respiratory tract and on the skin of humans. In healthy people, the bacteria generally does not cause disease, however, in people whose immune system is

depressed or skin is broken after a wound or surgery, MRSA can be the source of a significant infection. The challenge in the management of MRSA infections stems from the fact that the bacteria may be resistant to a wide range of antibiotics and, thus, treatment options can rapidly become limited.

S. aureus is not considered a common flora of dogs and cats, which are colonized by different staphylococcal species such as S. intermedius. Therefore, MRSA is usually not a natural occurrence in pets. The bacteria can, however, survive on the skin and nasal passages of household pets but colonization is usually self-limited and clears up on its own in about 14 days. In terms of disease in pets caused by MRSA, it is safe to assume that the same principles from human medicine apply and that the bacteria can be pathogenic in animals with wounds or depressed immune system. There is a consensus, however, that MRSA in animals is considered a reverse zoonosis, meaning that humans are the ones infecting pets. This is supported by the fact that, as previously mentioned, MRSA infection in pets is usually transient. Furthermore, studies have shown that dogs infected with MRSA reflect infection in the human population. This is significant because affected individuals can infect their pets, which can in turn re-infect their owners. This is the reason why collaboration between physicians and veterinarians is crucial when trying to get rid of an infection and thoroughly control MRSA in a household.

Human and animal health are intricately linked, and that may be even more apparent when it comes to companion animals. Most pet owning families share a close bond with their dogs and cats which can put them at greater risk of zoonotic infections, however this does not mean that they should give their animals away and not be exposed to the benefits of animal companionship. What needs to be done is to treat these pets as members of the family and thus provide them with appropriate care to ensure they remain healthy. The general guidelines to prevent transmission of zoonoses from pets to humans are very similar regardless of the diseases in questions: prevent pet contact with wildlife, frequent deworming, maintaining up-to-date vaccines and proper hygiene practices. Dealing with health problems in pets at an early stage is also more likely improve the animal’s health, reduce costs of treatment and decrease likelihood of transmission of disease to people.

Pet veterinarians play a crucial part in maintaining a healthy family. (http://www.ct.gov/dph/cwp/view.asp?a=3143&q=388948)

Resources:

Rabinowitz PM & Conti LA. 2010. Human-Animal Medicine. Saunders Elseviers ed.

Weese JS & Fulford MB. 2011. Companion animal zoonoses. Blackwell Publishing.

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Posted in All posts, Zoonoses

Posted by: glamielle | May 24, 2011

World Conference on Veterinary Education Report – May 13th-15th, 2011, Lyon, France

The year 2011 represents a significant milestone for the veterinary profession as it is the 250th anniversary of the first veterinary school in Lyon, France. To commemorate this important date, the 2nd World Conference on Veterinary Education was held at the veterinary university of Lyon, now known as Vet Agro Sup.

Claude Bourgelat, founder of the Veterinary Profession

The origins of veterinary education and the profession itself can be traced back to the initiative of French barrister Claude Bourgelat. Noticing discrepancies in knowledge of equine anatomy in previously published resources, he decided to collaborate with human surgeons in order to address the issue. It was after this cooperation that he recognized the similarities between the “human and animal machine” and considered the opportunity for an “animal doctor” profession. He later managed to secure an audience in front of the King Louis XV and argued that the creation of a school to publicly teach veterinary medicine would significantly benefit the country’s agriculture in combating cattle diseases such as Rinderpest. The King authorized his request and the first veterinary school was created in 1761 in Lyon, followed by Maison Alfort near Paris in 1766.

The World Conference on Veterinary Education, sponsored by various international organizations such as OIE or Merial, reunited some 250 delegates from educational entities worldwide and largely celebrated this history of veterinary education and Bourgelat’s initiative. However, much focus was also put on the future of veterinary education, in particular how to improve current veterinary curricula in developed countries as well as in the developing world. Notable attendees included representatives from the AVMA, OIE, AAVMC and a multitude of international veterinary schools.

Commemorative statue of Claude Bourgelat at the veterinary school in Lyon.

A recurring topic throughout the conference was that of the OIE’s & AVMA’s Day One Competencies. These provide guidelines to veterinary universities on specific areas of focus to teach students in order form competent veterinarians at the time of graduation. There was some discussion on potential enforcement of such guidelines by the OIE as well as the idea of a global veterinary school accreditation system. The OIE, however, argued that their role is not to oversee global veterinary curricula and that the guidelines provided are voluntary.

There was also significant mention of the need to integrate One Health into veterinary curricula, however, only few presentations provided concrete examples. I offered Western University’s perspective as I talked about the school’s Inter-Professional Education (IPE) curriculum (see previous post for more info) through my presentation: Inter-Professional Education – Training Veterinary students in a One Health Context. Western’s IPE curriculum brings together students from 9 health colleges covering human and animal needs and teaches these students how to approach health issues with a teamwork perspective as opposed to have each health profession isolated. At the basis of One Health is inter-professional cooperation and programs such as Western’s IPE provides a framework for communication and cooperation between health professions. I believe that adding skills in inter-professional cooperation could be a beneficial addition to the OIE’s Day One Competencies.

Western University's IPE curriculum is an example of applied One Health concepts to veterinary education.

Other points of focus included addressing animal welfare issues in veterinary education. This can mean training students to recognize and address such issues once they become graduates, but also to provide education that minimally harms animals. There were several interesting presentations touching on this, notably from the University of Nottingham in the UK.

This 250th anniversary of veterinary education reminds us that, while forgotten until recently, One Health was at the genesis of the veterinary profession. Claude Bourgelat himself recognized the inherent similarities between human and animal medicine and actively cooperated with human surgeons to expand veterinary knowledge. Also, it is important to recognize that Bourgelat’s efforts to create veterinary schools in 1761 came as a consequence of a significant outbreak of Rinderpest decimating Europe’s agriculture. The year 2011 is not only the anniversary of the veterinary profession but also the year that Rinderpest has officially been eradicated from the globe.

Thanks to the Dean of Vet Agro Sup, all the staff and students for their tremendous work organizing this conference.

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Posted in All posts, Conferences & Events, Education, France

Posted by: glamielle | April 19, 2011

Wildlife and Public Health – Working with marine mammals at TMMC

Increases in resource consumption and waste production associated with booming human development in the past hundred years have profoundly altered our environment. However, the question remains: how can we measure these changes adequately? One tool at our disposal is the study of animals in the wild. Wildlife, especially top predators, provides a good marker of environmental health and an abundance of these predators often reflects a healthy ecosystem.

I recently had the opportunity to visit The Marine Mammal Center (TMMC) in Sausalito, CA , where I met with fellow Western University 2009 graduate, Dr. Vanessa Fravel. The center offers state of the art facilities for the study and rehabilitation of stranded marine mammals such as California sea lions, Northern elephant seals or harbor seals and thus provides us with a better understanding of the interactions between wildlife, environment and public health. Just as with other animals, marine mammals can share a wide variety of diseases with humans and diagnosis of such pathogens in these species can help identify an outbreak in the environment and thus lead to preventive actions to aprotect the human population.

Such zoonoses include bacterial diseases (leptospirosis, brucellosis) but also fungal (coccidiomycosis), viral (influenza A & B, rabies) and parasitic (Anisakis). A more comprehensive list of zoonotic diseases shared between people and marine mammals can be found on this UC Davis webpage. Many of these diseases are present in both marine and terrestrial environments and studying their prevalence in wild marine mammals can help identify if these pathogens are naturally present in these animals’ environments or if they represent runoff from a land-based outbreak.

Taking a urine sample on an anesthetized California sea lion to look for Leptospira

Centers like TMMC are also very well placed to assess maritime ecosystem health, through evaluation of predatory species numbers or prevalence of environmental toxins. One such toxin has gained much attention in the marine mammal field in the past. Domoic acid has been linked to several sea birds deaths as well as marine mammals strandings, including a recent event involving sea lions in Santa Monica, CA in the USA. The toxin is produced by algal diatom Pseudonitzschia sp. The algae are naturally present in the environment and can be found at every level of the oceanic food chain beginning by absorption of the toxin by filter feeders such as clams and small fishes. While non-toxic at low levels, predators such as sea lions eat a large amount of these fish, leading to very high domoic acid tissue levels.

Dr. Fravel closely monitoring anesthesia in a California sea lion. The animal recovered uneventfully

The toxin principally affects the hippocampus and the most recognized clinical appearance of affected animals is neurologic in nature, represented by bouts of seizures as well as altered behavior. The signs are irreversible and animals are gradually not able to hunt and feed properly leading to death. However, the toxin can affect several other organs and has been detected in cardiac tissues of subclinical animals. Antemortem diagnosis of domoic acid poisoning can be difficult but MRI scan of the brain can reveal lesions in the hippocampus, however most diagnoses are made during necropsy once the animal has died.

The amount of fish people eat compared to marine mammals is minimal and as such, domoic acid poisoning in people does not lead to such extreme symptoms as seizures. However, the toxin is recognized to be the etiology of Amnesic Shellfish Poisoning (ASP) in humans through ingestion of contaminated shellfish, especially in periods of diatom blooms. Symptoms in humans also reflect involvement of the hippocampus and include short-term temporary memory loss, which can be permanent in severe cases.

While naturally present in the environment, scientists agree that blooms of domoic acid-producing algae are increasing. Reasons for this trend are most likely multifactorial and it remains to be seen whether causes include natural algal life cycle, global weather changes or increased nitrogenous agricultural waste runoff into the ocean (a phenomenon often associated with blooming of various algal species).

The diatom Pseudonitzschia, responsible for domoic acid poisoning (image from: http://www.sbnature.org/crc/425.html)

Once again, a One Health perspective allows us to recognize the inter-dependence between human, animal and ecosystem health and it is only through careful analysis of all of these factors that we can improve public health through an efficient and long lasting approach.

Zoonotic disease warning sign at TMMC - Always a good reminder when working with animals

More information:

Dierauf LA & Gulland FMD. 2001. CRC Handbook of Marine Mammal Medicine. Second edition. CRC Press ed.

Washington State Department of Health – Domoic Acid

National Oceanic and Atmospheric Administration (NOAA) – Domoic Acid Factsheet

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Posted in All posts, Environmental health, USA, Wildlife, Zoonoses

Posted by: glamielle | April 3, 2011

Animal Welfare and Public Health

The role of veterinarians in promoting animal welfare is evident and explicitly stated in the AVMA’s Veterinary Oath, along with their involvement in protecting public health.

Veterinarians are therefore at the perfect intersection of these two ideas that may seem somewhat unrelated. While it is part of my ethical beliefs that unnecessary suffering in animals should be prevented, it is important to recognize that promoting animal welfare goes beyond an ethical imperative, it is also a necessary step to improving public health.

The concept of promoting welfare in animals is often brought up in most industrialized countries, however, it is in the developing world that the majority of animals suffer neglect or mistreatment.

Treatment of animals in various countries is largely dependent on cultural context and is influenced by experiences, education, religion, community, among other factors. Many who live in developing countries don’t always view animal welfare as a priority. We must remain open-minded when we approach these communities as Westerners and try not to impose our values of ethical treatment of animals in these regions where the people themselves are struggling to survive and improve their own welfare.

However, One Health gives us the tools to improve treatment of animals by promoting public health. Indeed, developing communities need to see how promoting proper animal welfare can benefit them. This doesn’t so much stem from a feeling of selfishness but rather a need for self-preservation.

One of my patients in Morocco, presented plantigrade on the left rear leg and I suspected Achilles tendon rupture. The dog suffered a laceration injury on that leg from a knife wound during a fight. Left: suturing gastrocnemius tendon ends. Right: post-operatively, the patient should not use the affected leg for the next month to avoid tension on the tendon. Unfortunately, the dog never presented for re-check examination.

Working in a free veterinary clinic in Morocco, I was often exposed to cases of animal neglect or mistreatment (although to be fair, I must also recognize that many of my clients treated their animals very well). These usually included malnourished animals, as their owners often gave them scraps of their meal or a diet based on milk and bread. As a veterinarian, educating the owners on proper animal handling and nutrition was an important part of my work, along with deworming these patients, reducing intestinal parasite load and decreasing the chance of zoonotic transmission.

This dog presented with a laceration from unknown origin. Although the owners said it had just happened, it was evident during examination that laceration was several days old. The wound was flushed, debrided and closed. The patient recovered uneventfully.

Dog aggression was also a major issue, which often made it difficult to work with some patients. There was a belief among many owners that proper dog management was through violent repression of unwanted behavior. Naturally, some animals became very fearful of human contact, which translated into aggression. Aggressive dogs can become unpredictable and more prone to biting. This has a direct effect on public health as bite wounds can often lead to grave injuries, especially in children. Furthermore, a study from 2007 done by the Moroccan Ministry of Agriculture looked at rabies statistics in the country. Researchers saw that dogs were the main vector for transmission of rabies to humans and that cases of human rabies averaged 22/year. It is important to remember that rabies remains a largely incurable disease. The study also indicated that dog fighting was implicated in the transmission of the virus to people.

Large abdominal hernia in a mule. Lesions like this one can cause intestinal entrapment and torsion, often fatal without significant surgical intervention. A large number of patient presented with similar conditions, which may be related to excess pressure on abdominal wall from long-term carrying of heavy loads.

While the link between animal welfare and public health is clear looking at this previous example, it is even more direct when one looks at working animals. Many people in developing countries depend on animals such as livestock to survive, whether it is for consumption or transport of loads. The center of the Moroccan town of Fès, called the Medina, is a network of medieval streets only accessible to pedestrians. As such, merchants largely use animals such as donkeys and mules to transport goods. Thus, neglect or malnourishment of these animals can severely affect these merchants’ businesses if they are unable to reach parts of the city and it makes sense that keeping these animals healthy is essential for the wellbeing of the people depending on them.

Overgrown hoof in a mule. Conditions like these can lead to permanent damage to hooves and tendons, causing chronic pain and lameness.

From my experience in North Africa, animal mistreatment often originate from lack of education or proper understanding of what these animals need, weighed against the people’s own needs. Education always plays a pivotal role in development of populations and it is important that leaders in animal health such as veterinarians be good resources on proper animal management practices. However, when trying to promote animal welfare in culturally diverse environments, it is also important to recognize the local cultural or religious values that guide these communities. We must find ways to work within this framework if we want the changes to be well-received and integrated in the lifestyle of these communities. This is why cooperation with local leaders such as governmental but also religious is essential.

Lastly, I want to share an example in the United States where improving animal welfare led to a benefit to both the animals affected and the people depending on them. Dr. Temple Grandin, professor at Colorado State University, was concerned over the state of distress of various livestock species in agricultural settings. Drawing on experiences with dealing with her autism, she recognized similarities between prey species and autistic behaviors and used that insight to improve animal’s conditions in farms. Chronic stress in animals can lead to several adverse effects such as increased susceptibility to diseases, failure to thrive or physical trauma when panicking animals injure themselves. As farmers lost significant numbers of cows from stress and self-inflicted injuries, she approached them with plans for improved facilities that made use of the animals’ natural behaviors to reduce handling stress. Changes included curving corrals so that cows could only see few animals ahead of them but also avoiding use of objects prone to scare animals such as reflecting surfaces, smooth floors or chains. These improvements lead to reduced mortality rates in cows used for agriculture and thus increased production and benefits for farmers, a win-win situation. Of course, conditions of farmed animals can still improve but Dr. Grandin’s changes have largely become the norm when managing livestock in the USA.

Example of curving corral developed by Dr. Grandin. (image from: http://www.grandin.com/design/design.html)

It is important to realize that animal welfare should not just be the agenda of animal activist groups, but rather an important component of public health and animal production activities. This idea is spreading within international organizations such as the OIE, which include promotion of animal welfare on their list of objectives. As human population grows and human-animal contact increases, we must be proactive and determine how we can best serve both the health of populations and the animals they depend on.

For more information on animal welfare:

Gregory NG. 2004. Physiology and behaviour of animal suffering. UFAW Animal Welfare Series. Blackwell Publishing, Oxford.

American Veterinary Medical Association – Animal Welfare

OIE – Animal Welfare

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Posted in All posts, Animal Welfare, Morocco, USA

Posted by: glamielle | February 20, 2011

One Health Congress Report – Feb. 14th-16th, 2011, Melbourne, Australia

The 1st congress dedicated to the One Health movement was just held in Melbourne,  from February 14th-16th, 2011 and attracted hundreds of health professionals from all over the world.

Skyline view of Melbourne

Melbourne amazed the attendees by its vibrant architecture, modern cityscape & lively citizens. The congress was held at the Melbourne Convention Centre and offered its state of the art facilities to presenters.

The opening ceremony acknowledged aboriginal culture and respect of nature through traditional welcoming dances, followed by a speech by Peter Doherty from University of Melbourne and first veterinarian recipient of the Nobel Prize for his works in microbiology. From there, the program was packed with lectures and talks representing the diversity of One Health, divided into plenary sessions and smaller box sessions addressing specific themes.

Martyn Jeggo, Co-chair of the Organizing Committee, welcomes the attendees

Attendees reflected the diversity of the One Health movement and included many veterinarians, some human medical professionals, students, researchers and environmentalists. International organizations were also present such as the CDC, WHO, FAO, UN, WCS and USDA. Finally, there was a significant representation from governmental bodies including the Governments of Australia, Canada, Thailand as well as the European Union. Western University was also very well-represented as they were 4 of us at the conference presenting on various topics.

Cystic echinococcosis, considered a neglected infectious disease by the WHO is overrepresented in developing countries

I presented on my work in Latin America (see previous post) entitled Cystic echinococcosis prevention in the Highlands of Peru – A multidisciplinary perspective, under the banner of Neglected Zoonotic Diseases. These diseases usually remain on the sidelines of international attention but still kill millions worldwide. They are often driven by social factors such as human practices, poverty or development and are the perfect example of how One Health can benefit communities afflicted by such illnesses.

Other speakers provided us with practical examples of how the multidisciplinary approach of One Health has been applied from research to other health-related programs locally and internationally.

An interesting discussion regarding the definition or scope of the One Health movement was initiated by Jørgen Schlundt of the Danish National Food Safety Institute, who pushed for a more restrictive definition of One Health to “reduction of human disease through prevention of animal disease in all ecosystems”. His arguments were valid in the sense that we need a clear and simple idea of how to describe One Health to others, including governments, media, sponsors or the public. He further developed that if we focus on a single theme and build credibility and acceptance of the One Health movement using this issue as a support or example, we may then branch out and include other perspectives, such as social and mental health or non-transmissible diseases. Others responded that definition of health varies across the geographical and cultural spectrum and that social components of health are inherently part of One Health.

On this issue, I must say that I agree with both perspectives. One Health is indeed a very broad philosophy that can help us bridge and combine all aspects of global health, as it should be. However, I do have to side with Dr. Schlundt, to a certain extent. One of the recurring conclusions of the conference is that we need to keep the One Health momentum going. I think we all know in our hearts that One Health encompasses social issues, mental well-being and other non-transmissible illnesses. However, I also think that if this movement is to survive, we must simplify its meaning in order for others to understand it, and eventually support it. We must build a sort curriculum vitae for One Health to show the world what it has done as a movement and that such approach works. If we try to fix all of the planet’s problems at once, we will end up doing nothing and I am afraid that for the 2nd planned One Health congress to be held in 2 years time, we will be at the same place as today. Once we manage to build proper networks and channels and once One Health has become an established and respected idea, we can (and should) then expand its definition to other health-related fields. I do disagree with Dr. Schlundt, however, on the fact that, while zoonotic diseases are important, diseases affecting food safety and security should be included in this narrower definition of One Health (in fact, both fields often overlap). Hunger is one of the most important issues in the world today and One Health is the perfect platform to address it.

Another idea that came through the congress is that One Health doesn’t belong to anyone and I urge those who feel that the One Health perspective applies to their work, even if it relates to non-communicable diseases or social issues, to go ahead and bring this philosophy to their projects. As a small animal veterinarian, I do feel that the human-animal bond does belong under the One Health banner and I will try to include it in my work whenever I can. I just don’t think that it should be in the priorities of the movement as a whole right now.

Michael Alpers presented the movie "Kuru - Science and Sorcery" about his pioneer work leading to the discovery of prion diseases

The needs for a One Health paradigm is clear looking at the following statistics:

- By 2020, 50 million people will be environmental refugees, fleeing change in weather affecting their livelihoods

- One billion of people suffer from hunger worldwide (1/7 people)

- About 60% of emerging infectious diseases of humans come from animal origins

No single approach can solve these “wicked problems”, however in order to do things right, we cannot rush things. I would personally like to see a roadmap of what One Health should accomplish in the near future and maybe some objectives that the movement will try to attain as a whole before we hopefully meet again in Thailand in 2013. We need to progress step by step and build a strong base before we can expand.

This is the synthesis of my feelings towards One Health at the close of this first conference, and I am ever more motivated, especially now, to be part of it and see it progress and evolve over time.

I welcome people’s thoughts or comment and hope for a constructive discussion so that we can have a clearer picture of who we are as a movement and where we should be heading.

I also would like to thank the organizers of this congress Martyn Jeggo, John Mackenzie and their team for their tremendous work and for giving me the opportunity to meet and interact with so many others who are as passionate as I am about One Health.

Victoria's Great Ocean Road offers truly breathtaking vistas such as the Twelve Apostles pictured here

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Posted in All posts, Australia, Conferences & Events

Posted by: glamielle | October 5, 2010

Working in Morocco – Recurring leishmaniasis in a canine patient

For the past month, I have been working as a volunteer veterinarian at the American Fondouk, a mixed animal hospital in Fès, Morocco. The clinic offers free veterinary care to its patients and sees all sorts of animals from dogs and cats, to horses, donkeys, birds, sheep and goats. I chose this site to get more experience in promoting veterinary care in communities with limited resources as well as to see more public health-related cases.

The American Fondouk in Fès, Morocco offers free veterinary care to the community.

After a few weeks, I had the occasion to be exposed to such a case. The veterinary student externs were presented with an adult male German shepherd with recurrent epistaxis and crusting skin lesions on his face and ears. Upon closer examination, the lesions were distributed around the nose, eyes as well as the ear tips and were characterized by exfoliative dermatitis and ulceration. Ocular examination revealed bilateral anterior uveitis, keratitis and conjunctivitis.

Adult German shepherd with clinical appearance suspect of cutaneous leishmaniasis.

Due to the history and clinical presentation, leishmaniasis was suspected. I scraped the affected area around the right eye using a scalpel blade to clear the debris until bleeding was noticed. I then made an impression smear of the bleeding lesion which was stained with Diff Quick. During microscopic evaluation of the sample, I noticed macrophages with intracytoplasmic structures characteristic of infection with Leishmania. The dog had previously been treated with allopurinol, with unfortunately no improvement and euthanasia was elected due to the poor prognosis.

Macrophage from a direct smear of a periocular lesion. The intracytoplasmic inclusion bodies are consistent with Leishmania protozoans. (excuse the low quality of the picture...)

Leishmaniasis is a protozal disease seen in several different animal species as well as humans. It is distributed worldwide and affects millions of people each year. There are about 20 different species of Leishmania sp. and disease presentation can vary depending on the protozoan type.

Leishmania is present as a motile, flagellated protozoan in the vector, the sand fly (Phlebotomus & Lutzomyia), which feeds on mammalian hosts. As the parasite enters a host, it becomes non-motile and reproduces inside macrophages. The life cycle completes when another sand fly ingests a blood meal from an infected host. Wildlife reservoirs for the protozoan include rodents, hyaxes, dogs or foxes.

Life cycle of Leishmania sp. (http://www.dpd.cdc.gov/DPDx/html/Leishmaniasis.htm)

In North Africa, Phlebotomus sp. acts as the vector. However, in the United States, there have been reports of direct transmission, without the presence of an appropriate vector; direct transmission from a bitch to her pups has also been reported in the USA.

The Phlebotomus sand fly, vector of leishmaniasis in North Africa, is smaller than a mosquito and active throughout the night. (http://www.life-of-science.net/medicine/)

In animals, the disease is most commonly seen in dogs, although cats and horses can also show signs of infection. Canine leishmaniasis can have visceral, cutaneous and systemic component (although multiple forms can occur in a single animal). Clinical presentation is similar to the patient above and there is often cutaneous involvement. Other clinical signs present in dogs include anorexia, fever, lymphadenopathy and renal failure (the main cause of death in unmanaged cases). The disease in cats and horses is usually milder and is characterized by non-healing ulcers on the ear tips or muzzle.

Treatment in dogs is often unrewarding and no good protocol has been found yet. Common medications used include allopurinol or Pentostam (sodium stibogluconate). Even well-managed patients can show high rates of recurrence.

Human disease also varies in clinical appearance. Cutaneous manifestations can be simple or diffuse and are usually characterized by nodules on exposed areas of skin (most often face & hands), which can develop to ulcers. Simple cutaneous infection is often self-limiting while the diffuse form can be lifelong. Symptoms of visceral leishmaniasis in people (Kala-azar) include weight loss, fever, splenomegaly and hepatomegaly. Once again, the illness can resolve on its own, however, in immunocompromised or malnourished individuals, the disease can be fatal. Resolution of the visceral form can also be followed by the cutaneous form. Mucocutaneous leishmaniasis is a more aggressive form found primarily in Latin America and is characterized by erosion of the nose or oropharynx.

Treatment in people is often long and depends on the form of the disease, geographical location and species of Leishmania. Pentostam and meglumine are often used; guidelines from the World Health Organization (WHO) also include the use of amphotericin for visceral leishmaniasis.

From left to right: visceral, mucocutaneous & cutaneous leishmaniasis. (http://wiz2.pharm.wayne.edu/module/antiparasitic.html)

Infection rates in people and animals are increasing worldwide and it is important to look to environmental factors to explain this trend from a One Health perspective. Some of these factors include increased human-wildlife contact, such as in newly deforested areas where populations have increased contacts with sand flies. Another theory that has been put forth regarding many arthropod-transmitted diseases is global warming. As average summer temperatures rise, vectors find more suitable environments and establish persistent populations at higher latitudes.

For more information on Leishmaniasis:

Leishmaniasis – CDC

Leishmaniasis – Iwoa State Center for Food Security and Public Health

Rabinowitz PM & Conti LA. 2010. Human-Animal Medicine. Saunders Elseviers ed.

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Posted in All posts, Morocco, Zoonoses

Posted by: glamielle | August 21, 2010

One Health in education

(Courtesy of Western University)

One Health promotes a multi-disciplinary approach to public health, in which professionals from different backgrounds must work together for a common goal, each adding their part to the puzzle that is public health.

At a basic level, it requires health professionals to be aware of responsibilities of other health-related fields.

Short-term strategies to establish a One Health approach include having current health professionals communicate and encourage multi-field cooperation. This is a conscious transition that these professional have to make. A more long-term solution is to expose professionals to One Health during their training and give them the tools for efficient inter-disciplinary cooperation as they become prepared to enter their respective professions.

Western University of Health Sciences, located in Pomona CA USA, started in January 2010 its first Inter-Professional Education (IPE) curriculum. The program reunites 1st and 2nd year students from the 9 colleges present on campus into groups of 8 or 9 as they are exposed to cases written by various professors. These cases may focus on one specific aspect of medicine or health, but are inter-disciplinary in nature (just like real life) and every team member adds their own perspective and experience to solve the problem presented to them with a multi-faceted approach. The Problem-Based Learning (PBL) curriculum promotes discussion and cooperation between the students and exposes them to the work of their peers. PBL requires that each group is facilitated by a faculty member, however, this person only monitors the discussion and this is overall a student-oriented process. The group members are responsible for steering the analysis of the case and its progression. The elect which strategy would be beneficial to follow and identify what issues or concept are important.

I had the occasion to participate to this IPE courses as a facilitator (faculty member) responsible for several different student groups. This was a unique experience, to sit in the facilitator’s chair, after having been taught veterinary medicine at Western myself through a PBL system. Group dynamics largely depended on individual student personalities, however, the most interesting aspect for me was to see how these students’ views on other health-related professions changed during the course. During my professional career, I have noticed that people do not always appreciate the range of work executed by veterinarians and IPE is a way to introduce these health professions to one another.

The hopes are that, after graduation, work in inter-disciplinary teams will be easier for these students as they will have been exposed to the challenges of such environment.

The course is mandatory for all students enrolled in 1st and 2nd years at Western University, regardless of their future professional interests and some may not see themselves working in the public health field. It is important, however, to remember that every health professional is a public health advocate and that a better understanding of One Health starts with a better understanding of health professions in general.

For more information on Western University’s IPE program, check out their website.

Note:
Western University is home to 9 colleges:

Osteopathic Medicine (COMP), Allied Health – PT, PA, MSHS (CAHP), Pharmacy (COP), Graduate Nursing (CGN), Veterinary Medicine (CVM), Dental Medicine (CDM), Podiatric Medicine (CPM), Optometry (CO) & Biomedical Sciences (GCBS)

(Courtesy of Western University)

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Posted in All posts, Education, USA

Posted by: glamielle | August 21, 2010

Echinococcosis prevention in the highlands of Peru

The communities studied were often remote and had limited access to medical facilities

Zoonotic diseases most often affect populations of the developing world, as exampled by tuberculosis, an illness largely eradicated from developed countries but still present in poor communities. The relationship between poverty and such diseases are multifactorial in nature but heavily influenced by lack of education, inadequate funding or little international interest in these pathogens.

I was able to witness these relationships as a 4th year veterinary student at Western University. Our curriculum enabled us to set up rotations in specific areas of interest and I naturally focused on public health. During one of these rotations, I and two other classmates spent one month in Peru with the San Marcos Veterinary Faculty in Lima, Peru. We participated in various local research projects regarding zoonotic diseases such as Chagas disease, neurocystisercosis, equine infectious anemia and methicillin-resistant Staphylococcus aureus (MRSA) prevalence in neighboring farms.

Our main work, however was in the Peruvian Highlands as we were actively participating in a prevention program against tapeworm Echinococcus granulosus. This is a parasites that is distributed worldwide, however there are several hotspots such as Peru, where human prevalence is thought to be around 9% in some parts of the country (one of the highest worldwide). Other hotspots include Northern Africa and China.

Life cycle of Echinococcus granulosus (http://www.dpd.cdc.gov/dpdx/html/Echinococcosis.htm)

The parasite’s life cycle is closely related to several domestic species, which greatly facilitates human transmission. Dogs are the primary host and the pathogens are shed in the feces. From there, they are eaten by a secondary host, in our case sheep, and escape the gastrointestinal tract to internal organs where they form cystic structures. This life cycle completes when dogs eat these organs along with the cysts.

A human radiologist came along for part of the research to help us identify hepatic hydatid cysts in sheep

Dogs remain relatively asymptomatic for infection as the parasite stays in the intestines, however sheep can show clinical signs as these cysts grow and obliterate internal organs.

In the Andean context, this life cycle is favored by a sheep-based agriculture and a large canine population, mainly used as herders. Native practices of home slaughtering of the sheep and feeding viscera to the dogs also greatly facilitate this life cycle. Human cystic echinococcosis is similar to the sheep disease as people are considered a secondary dead-end host (fortunately because we seldom get eaten by dogs, the life cycle doesn’t complete itself after human infection). The pathology is also similar in the sense that the tapeworm disseminates to internal organs, mainly liver and lungs, and forms slowly growing cystic structures, eventually leading to failure of these organs. In the Andean context, children are often the primary caretakers of the dogs and thus are at higher risk of exposure.

People often get infected at an early age as they care for the family's dog

Diagnostics in people and sheep is most efficiently done through diagnostic imaging such as abdominal ultrasounds or radiographs. Treatment is often difficult as medications can have difficulties reaching through the cysts and surgery is often necessary for complete removal. However, surgery itself is not without risks and rupture of the cyst during removal can cause dissemination of the parasites throughout the body and secondary cyst formation in the abdomen. Several methods have been developed to treat the infection such as the perforation aspiration injection and re-aspiration (PAIR) procedure, in which cystic fluid is aspirated and then replaced by medication. This procedure, however requires general anesthesia and advanced medical equipment, which is not always available in remote areas. In fact, in the some remote communities of the Andes, medical facilities can be virtually non-existent and infection in people can be undiagnosed until later stages.

Diagnostics in dogs can also be difficult since these animals are usually asymptomatic. Fecal floatation for egg identification can yield results, however, eggs are shed intermittently and it is impossible to distinguish them visually from other tapeworm eggs such as Taenia spp. Other methods include ELISA and PCR but these can be costly. The infection in dogs is efficiently resolved through the uses of praziquantel but, since the parasite is present in the environment, there are high rates of re-infection.

The culprit: Echinococcus granulosus, in a heavily infected canine fecal sample

Our work with the San Marcos Faculty included travelling to various Andean communities to promote knowledge of the

Fecal sampling in a dog. Samples will be analyzed for infection through fecal floatation and copro-ELISA

infection and its life cycle as well as testing alternate treatment protocols using more frequent praziquantel administration. We took blood and fecal samples from dogs presented to us by the villagers and gave them medication. Researchers would come at different time in the future to reproduce these steps and measure rates of re-infection in dogs. Along with that, I designed a knowledge, attitude, practices (KAP) survey to identify potential risk factors for human infection and administered the survey in a few of these communities. The fact that these were usually indigenous populations often made Quechua the favored language compared to Spanish and communications often required a translator. I found that knowledge of the disease was inconsistent and education is the first barrier for proper management and control of echinococcosis in these parts.

When considering zoonotic diseases, prevention is one of the most important aspects for eradication and control. These are often pathogens that are prevalent in parts of the world that do not have proper access to medical professionals, proper educational background or the economic power to implement ideal surveillance programs. In this context, there are specific practices that put people at higher risk of infection, namely feeding infected sheep offal to dogs or hygiene habits. If we want to be able to prevent human infection, we must educate the local population about the disease and implement proper slaughter protocols to break the life cycle of the parasite. A One Health approach is needed to recognize that reduction of disease in people is impossible without treating dogs and the environment in which they live and thus limit rates of re-infection.

While there is a lot of attention on emerging infectious diseases such as novel influenza strains or Ebola virus, we need to remember that there are countless chronic or re-emerging illnesses diseases that still affect millions of people worldwide, such as cystic echinoccocosis or leptospirosis.

Administering KAP surveys. Contact with the affected population was an essential part of the project.

 

More information:

Echinococcosis - Iwoa State Center for Food Security and Public Health

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Posted in Peru, Zoonoses

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