PARENT SESSION
Symposium 3: Emerging Diseases: Stressing the Union of Community Ecology and Epidemiology
Organized by: S Collinge and C Ray
Monday, August 4. 8:00 AM to 11:30 AM, SITCC Chatham Ballroom C.

The emergence of a new genus of lethal zoonotic paramyxoviruses in Australia and Malaysia.

Daszak, Peter^*,1, ¹ Consortium for Conservation Medicine, Palisades, NY, USA

ABSTRACT- Emerging infectious diseases (EIDs) are the key future threat to global human health through the emergence of previously unknown or novel zoonotic agents such as A.I.D.S. Zoonotic viruses (transmissible between humans and animals) make up 75% of known human EID agents. Therefore, predicting their emergence is a holy grail of EID research so far impossible to achieve. In the current talk, I focus on a new genus of viruses (Henipavirus) that emerged during the 1990s in Australia and Malaysia. These viruses have high human case fatality rates (>40%), no known therapies or vaccines, and a lack of knowledge of their range, biodiversity and ecology. The first Henipavirus to emerge, Hendra virus, killed 15 horses and 2/3 people in three separate outbreak events in Australia during the 1990s. The second, Nipah virus, was more devastating, killing over 100 people in Malaysia and Singapore during 1998-1999. Both viruses have fruit bat (Pteropodid) reservoir hosts and appear to require a domestic animal intermediate host (horses and pigs respectively) for transmission to humans. By analyzing recent changes in land use, agricultural patterns, climate, fruit bat migration and distribution, we are testing hypotheses on the anthropogenic factors that drove Henipavirus outbreaks. We have developed a preliminary matrix model for Henipavirus emergence that will be parameterized using these data to ultimately assess the risk of future outbreaks. Recent reports of Nipah-like virus outbreaks in Bangladesh and India, and the presence of antibodies in fruit bats of other southeast Asian countries suggest a wider biodiversity and distribution of this genus. Our approach will be directly applicable to predicting emergence throughout the Henipavirus range as future viruses are discovered. Finally, the emergence of Henipaviruses highlights the double impact of some anthropogenic environmental changes that both reduce available wildlife habitat and promote the interspecies transmission of microbes.

Key words: virus, fruit bats, emerging disease