Global Health Vet – A One Health approach to public health

What the what?? Two posts 2 weeks apart? I know, I’m trying to make up for the lack of blog action so far this year. Oh and I went to a pretty interesting conference so I wanted to share.

I just came back from the International Meeting on Emerging Infectious Diseases (IMED), held in Vienna Austria and organized by the International Society for Infectious Diseases (ISID). This is the 2^nd time that I attend this conference (see post of last year) and this is one of the best One Health-oriented conferences that I’ve attended. It’s really invigorating to learn from those who are at the front lines of One Health.

Ebola

One of the major topic of the conference of course, was Ebola and several speakers presented about their hands-on experience with the current outbreak in West Africa. It was great to hear about the work done in the field, and especially to get a reality-check on the conditions and challenges encountered in this outbreak. As of October 25^th 2014, the total number of cases amounts to 10 141 people with the disease, with 4922 deaths. According to a presentation from Médecins Sans Frontières (MSF), the outbreak could have started as soon as December 2013 in rural regions of Sierra Leone before being spread to larger cities from movement of people. On the bright side, it looks like the mortality rate (percent dead from those infected) is lower (60-70%) than previously thought for Zaïre Ebolavirus, which is the deadliest strain of Ebola – and the one responsible for the current outbreak.

A presenter from the University of Witwatersrand, South Africa mentioned that outbreaks of diseases like Ebola are increasing. This could mean that we are better at finding these outbreaks (if we look more, we’ll find more), or it could mean that epidemics are truly rising. The presenter added a few potential reasons why this phenomenon may be happening:

• Better diagnostic capabilities making identifying the disease easier
• Increase in Ebola spreading among non-human primates (ex: chimpanzees)
• The epidemiology and ecology of Ebola may be more complex than previously thought
• The human population in endemic areas becomes more mobile, therefore spreading diseases more easily
• There is a larger human population, which encroaches into natural environments, where the virus is present

An interesting aspect of the current Ebola outbreak is the socioeconomic implication caused by the epidemic, which some argue are more deadly than the disease itself. For example, the stigma associated with Ebola cannot be neglected, both on the individual and national level. In fact, this outbreak, located in West Africa, has caused business to decrease with some other African nations, located thousands of kilometers away.

One of the most difficult factor to deal with in this epidemic is the local funeral ritual of cleaning the dead. When someone passes away, it is common for members of the family to meet and say their good bye to the deceased, which includes cleaning and even kissing the body. The number of people attending these events can range from 50 to 150 family members, some travelling long distances, and this practice has definitely played a big role in the explosion of the outbreak. Unfortunately, changing cultural belief can be very difficult. For example, some organizations started cremating the dead in hopes of preventing the spread of the virus. Unfortunately, this is not widely accepted and it convinced people not to contact authorities when faced with the possibility of Ebola in their household. Finding control methods that are accepted by the local population is an imperative when dealing with disease outbreaks and unfortunately, the solutions may be difficult to find.

Other challenges encountered by the teams in the field include the shutdown of local public health structures, which includes lack of proper infection control or isolation protocols. In countries with the least numbers of doctors per capita, any disruption of the health system can have disastrous consequences.

Finally, one presenter touched on the misinformation that plagues the efforts to control the disease in West African countries. There are many outrageous beliefs about Ebola held by some, including that the outbreak is a government scam, and some government officials have even claimed to have stocks of Ebola vaccine and treatment – when in fact there is no such thing yet.

In spite of this mountain of challenges, the rate of infected seems to be decreasing, thanks to the enormous effort from both local and international health workers have risked their lives fighting this disease.

Middle-East Respiratory Syndrome Coronavirus (MERS CoV)

With Ebola monopolizing the air, it is easy to forget that another disease is also a cause of concern, especially in the Arabian Peninsula: MERS CoV. Contrary to Ebola, this is a virus that was never seen before the 1^st case appeared in Saudi Arabia in 2012. It is interesting to revisit this disease at IMED and when I attended the last conference, the disease had been known for only 5 months. Now, 2 years later, cases of MERS CoV are still popping up and the source of the virus remains in questions.

Since last year, however, a lot of studies into potential animal reservoirs have been done. Although the true origin of this pathogen remains unknown, the picture has become clearer regarding animal species that could implicated in spreading the virus. Using the lessons from the Severe Acute Respiratory Syndrome (SARS), a previous virus that bears a lot of similarities with MERS, researchers looked into the possibilities that local bats may be harboring the pathogen. Some bats have been found to carry pieces of the virus, in the form of RNA, thus indicating that these animals could play a role in the spread of disease. Attention was also turned on camels. Interesting findings of multiple research projects have shown that camels throughout the Middle East and also parts of Africa possess antibodies against this disease. As such, they were exposed to the disease in the past. One theory is that the virus jumped from bats to camels somewhere in Africa and that the camel trade may have brought the virus to the Arabian Peninsula, where humans became infected. In addition, experimental infection of camels with MERS CoV have shown that the animals became mildly sick but were able to shed large amount of virus from their respiratory tract. However, the fact that only 1/3^rd of humans infected with MERS CoV reported having contact with camels leads many to believe that, while camels and bats may be a big part of the MERS puzzle, other factors leading to transmission of the virus to humans must be present. Investigating disease ecology often takes time at it may be a while before we fully understand the dynamics of MERS – after all, only last year did we positively identify the bat origins of the SARS virus, when the outbreak occurred over 10 years ago. Hopefully, even more will be known at next year’s IMED conference.

Update on international organizations:

Conferences like IMED are a great way to learn more about the work done by international public health organizations, and it was great to hear about the work done by these groups.

I have mentioned EcoHealth Alliance several times in some of my previous posts and representative from this organization spoke at IMED. One of the talks that I thought was interesting was regarding bats as vectors for viral zoonoses. With all the serious diseases potentially by bats (Ebola, SARS CoV, rabies, Hendra & Nipah viruses), a lot of attention has been put on identifying what makes these animals so special when it comes to transmission of diseases to humans. One theory was that bats may carry more viruses compared to other animal species. The work done by EcoHealth Alliance showed that bats themselves do not carry more viruses, however they (along with rodents and primates) do harbor more zoonotic viruses compared to other animals.

The World Organization for Animal Health (OIE) presented about their disease mapping system. The OIE gets report of diseases in animals and maps them on their World Animal Health Information System (WAHIS) portal. The information they gather is very detailed and includes: numbers of animals affected, control measures, morbidity and mortality rates and more. Recently, the OIE started a WAHIS – Wild  mapping portal where diseases of wildlife can be monitored. In times where an increasing number of human infections come from animal origins, it is paramount to keep track of diseases in both domestic and wild animals in order to reduce likelihood zoonotic spread.

Finally, a presenter the Food and Agriculture Organization of the United Nation (FAO) gave a great presentation on the changing disease landscapes and challenges to improve animal and human health in an ever-changing world.

Of course, there were many great talks (and posters) during IMED and I cannot go over all the cool things I learned there…so you’ll just have to go there yourself next time (and maybe I’ll see you there).

Yours truly, presenting a poster about flea and tick infestations