Investigating seasonal drivers of viral zoonoses from Madagascar fruit bats

Zoonotic pathogens derived from an animal reservoir account for some 60-75% of emerginginfectious diseases in humans, a disproportionate number of which take place in resource poorcountries where the economic and social burden of corresponding health crises is greatest. Bats havereceived much attention in recent years for their role as the putative reservoir hosts for a number ofhigh profile, virulent zoonoses, including Ebola and Marbug filoviruses, Hendra and Nipahhenipaviruses, and SARS coronavirus, all of which demonstrate peaks in transmission-both betweenbats and from bats to spillover hosts (including humans)-during the resource-poor dry season for thesystem in question. Seasonal forcings are known to play an important role in driving epidemic cycles ininfectious diseases for both humans and wildlife, though the mechanistic drivers of seasonality cansometimes be difficult to identify. In bat systems, researchers have posited that dynamical patternscould result from pulsed additions of annual, synchronous births to the pool susceptible to immunizingviruses, while others have suggested that bats might instead maintain these viruses as persistentinfections across the duration of their lifespans and undergo periodic bouts of viral shedding. A trueunderstanding of these dynamics will be essential to predicting and preventing the next bat zoonosis, acritical public health aim for developing world countries, like Madagascar, where we base our work. Todate, longitudinal data of a fine enough scale do not exist to distinguish among the proposedhypotheses. Our project brings together a diverse team of molecular biologists from Institut Pasteur deMadagascar and Duke-NUS, epidemiological modelers from Princeton, and field ecologists fromHarvard to address these challenges. In Aim 1 of our research, we introduce novel Luminex assays toidentify henipaviruses, filoviruses, coronaviruses, and lyssaviruses antibodies in both bat and human serum samples in Madagascar.In Aim 2, we build mechanistic transmission models exploring the proposed hypotheses of seasonaldrivers of infection dynamics in bat systems, and in Aim 3, we unite these goals in a longitudinal model-guided field study, with corresponding serological and molecular analyses, which will generate the dataneeded to enable effective model comparison and evaluation. Our work addresses questions of criticalinterest to both evolutionary biology and public health, while simultaneously building scientificcapacities in the developing world.