COS 17-2 - Joint circulation of viral diseases in a bat population

Tuesday, August 9, 2016: 8:20 AM
Palm B, Ft Lauderdale Convention Center
Noam Ross1, Jonathan H. Epstein2, Simon J. Anthony3, A. Marm Kilpatrick4, Ariful Islam3, Phoenix Lan Quan5, Jennifer Barr6, Ina Smith6, Carlos M. Zambrana-Torrelio1, Yun Tao7, Ausraful Islam8, Kevin J. Olival3, Emily Gurley8, M. Jahangir Hossein8, Hume E. Field9, Mark D. Fielder10, Thomas Briese11, Mahmud Rahman12, Gary Crameri13, Lin-Fa Wang6, Stephen P. Luby14, W. Ian Lipkin5 and Peter Daszak1, (1)EcoHealth Alliance, New York, NY, (2)Ecohealth Alliance, New York, NY, (3)EcoHealth Alliance, (4)Ecology and Evolutionary Biology, University of California, Santa Cruz, Santa Cruz, CA, (5)Center for infection and Immunity, Columbia University, (6)CSIRO Australian Animal Health Laboratory, (7)Environmental Science and Policy, University of California, Davis, Davis, CA, (8)International Centre for Diarrheal Diseases Research, Bangladesh, Dhaka, Bangladesh, (9)Animal Research Institute, Queensland Department of Primary Industries and Fisheries, Brisbane, Australia, (10)School of Life Sciences, Science, Engineering and Computing Faculty, Kingston University, London, UK, (11)Center for infection and Immunity, Columbia University, New York, New York, (12). Institute of Epidemiology, Disease Control & Research, Government of Bangladesh, Dhaka, Bangladesh, (13). CSIRO Australian Animal Health Laboratory, (14)Stanford University, Stanford California, USA

Bats are reservoir hosts for a wide variety of viruses, several with the potential to cause human disease. The Indian Flying Fox (Pteropus medius, formerly P. giganteus) is a large, colonial fruit bat species that lives in close association with humans in Bangladesh and are a known source of Nipah virus (NiV), which can cause fatal encephalitis in humans.

Here we examine the dynamics co-circulation of multiple viruses with spillover potential in a population of P. mediusin Bangladesh. In addition to NiV, we report on circulation of Ebola virus (EBOV) antibodies present in the same population.

As part of a broader study, we sampled bats from a population in Fardipur, Bangladesh quarterly over six-year period. We used a Luminex assay to measure levels of both NiV and EBOV IgG antibodies in bat blood samples. Using hierarchical general additive models, we examine longitudinal trends and seasonal patterns in antibody levels. We infer periods of peak infection and the role of seasonal reproduction in driving disease dynamics using age-structured SIR models.


Both NiV and EBOV infections exhibit seasonal dynamics driven in part by pulsed introduction of susceptible newborn bats into the population. Seasonal outbreaks vary year-to-year, with some years lacking a distinct period of infection. Exposure to EBOV infection occurs more quickly than NiV, with most bats exhibiting signs of first exposure during their first year. By contrast, exposure to NiV occurs later in life. This implies more efficient transmissiion of EBOV than NiV during the same contact events in this population.

We measure the loss of antibodies to NiV and EBOV in wild in recaptured individuals, finding that NiV IgG antibodies declined faster than EBOV IgG antibodies, suggesting shorter-lived immunity against EBOV. Differences in transmission dynamics and other virological properties may explain these differences in the dynamics of naturally infected bat populations and may have implications for spillover into other animals or human populations.

Slides and other related materials will be made available at prior to the presentation.