Global Health Vet – A One Health approach to public health

I just had the opportunity to attend to the International Meeting on Emerging Infections (IMED), held in Vienna, Austria where I presented a poster on West Nile Virus (WNV) surveillance efforts in Southern California (click here to read my previous post on WNV monitoring in wild birds).

Ugandan artist’s rendition of the Ebola outbreak presented at the conference by a speaker from South Africa.

The event united over 700 visitors from 99 different countries and presenters shared their experiences and findings on various issues regarding infectious diseases in both animals and people. One of the themes that was highlighted across the board was the need for an appropriate educational component when fighting emerging infections, especially in developing countries. Viruses like Ebola for example, that can cause severe disease in those affected, can be transmitted from animals to humans, or between people, due to specific habits that are practiced in areas at-risk. Ebola is present in wildlife and several outbreaks in Equatorial Africa have been associated with hunting and consuming primate meat. As the animal is hunted and prepared for food, the virus, found in the primate’s blood, can enter the hunter’s body through scratches or wounds. However, the virus is also shed in the saliva and secretions and contact with these fluids is the main way that this disease spreads to others once an outbreak has started. This is why attending the sick without proper personal protective equipment can cause transmission of the disease. Unfortunately, Ebola is often fatal and family members or friends who prepare the body for burial can also become infected by such activities. The speaker  of this particular presentation emphasized on cooperation with local leaders in order to increase efficacy of control measures. One such example was apparent when the presenter discussed traditional Muslim habits of preparing a body for burial, which has to be done in a certain way but can expose people to the virus. One crucial step in implementing intervention methods was to meet with higher Muslim leaders in the region as they only could grant exceptions to these burial practices once they understood the circumstances. This is a perfect example of how trying to manage outbreaks in any country without taking into consideration the local culture can fail, even if responders have all the appropriate medical tools at their disposal. A lot of great work is done by USAID in Equatorial Africa in order to understand the drivers for emerging diseases like Ebola.

Covering jars collecting date palm sap is a simple and effective way to prevent contamination from fruit bat urine and therefore, human transmission of Nipah, as described by this presenter from Bangladesh.

Another clear example of how human practices can affect disease dynamics is Nipah in South East Asia. This is a virus that can affect both animals, such as pigs, and humans and is shed by  fruit bats from their saliva and urine. Just like Ebola, Nipah can cause grave disease in populations exposed. It was striking to see various presenters talk about their different experiences dealing with this disease and how neighboring countries can have big effect on the number of people affected because of the smallest changes in habits. As an example, in Bangladesh, the disease is concentrated in what is called the “Nipah Belt” and researchers have spent time looking at what are some of the causes for this increased presence of Nipah in this region. One of the most important factor was the consumption of raw date palm sap. In order to collect this delicacy, a shaved area on the tree trunk is made and a jar collects the sap. As it turns out, fruit bats are also fond of the juice and will drink from the jar, contaminating it with their urine or saliva. In neighboring countries such as Thailand, raw date palm sap is not as commonly consumed, and villagers also cover the collecting jars more frequently, leading to a reduced likelihood of transmission of Nipah. It is amazing to see how small interventions at the local level can greatly affect the life cycle of a disease and save lives.

Another risk factor for the transmission of Nipah to people is forest fragmentation, leading to increased contact between bats and people. One Health teaches us that the interactions between humans and our environment can greatly promote zoonotic transmission of disease, or even the apparition of new pathogens. Some of the presenters shared hard evidence of this relationship between health and the environment. A significant focus was put on some of the issues that can arise from loss of biodiversity. One may think that a decreasing number of wild animals may mean reduce chances of transmission of zoonoses. However, some  researchers presenting at IMED advocated that biodiversity plays the role of a buffer for disease and in effect dilutes pathogens across multiple species rather than concentrating them into a few species, which we can then enter in contact with. Similarly, loss of animal diversity and specifically predators can lead to an increased number of prey species that can be considered as pests such as rats, which can transmit diseases like plague.

Finally, we were reminded of some of the challenges that promoting public health and preventing diseases can generate. As  one presenter suggested, successes with disease prevention result in lack of illness, and therefore, it can be difficult for policy makers and the public to see the benefits of such programs. This is why it is important to maintain infectious disease prevention projects existent or we will likely face a come-back of some major infections that were controlled, and as such invisible, in the past while these programs were in place.

Overall this was a very interesting conference and I think participants were exposed to a lot of different challenges in disease prevention, but also new tools and ideas that can help us meet and overcome these challenges. I left Vienna with a new sense of motivation and I can only hope to attend the next IMED conference, held in April 2014 in beautiful Cape Town, South Africa.

Quick visit of beautiful Vienna…The Schönbrunn park, hunting grounds of the Kaiser where we can find the Gloriette, a ballroom built in 1775.

For more information:

International Society for Infectious Diseases (ISID)

ProMED-mail – A great way to receive updates on disease outbreaks (from ISID)