The ecology of Nipah virus in Bangladesh: a nexus of land use change and opportunistic feeding behavior in bats

Abstract

Nipah virus is a bat-borne paramyxovirus that produces yearly outbreaks of fatal encephalitis in Bangladesh. Understanding the ecological conditions that lead to spillover from bats to humans can assist in designing effective interventions. To investigate the current and historical processes that drive Nipah spillover in Bangladesh, we analyzed the relationship between spillover events and climatic conditions, the spatial distribution and size of Pteropus medius roosts, and patterns of land use change in Bangladesh over the last 300 years. We found that 53% of annual variation in winter spillovers is explained by winter temperature, which may affect bat behavior, physiology, and human risk behaviors. We infer from changes in forest cover that a progressive shift in bat roosting behavior occurred over hundreds of years, producing the current system where a majority of P. medius populations are small (median of 150 bats), occupy roost sites for 10 years or more, live in areas of high human population density, and opportunistically feed on cultivated food resources - conditions that promote viral spillover. Without interventions, continuing anthropogenic pressure on bat populations similar to what has occurred in Bangladesh could result in more regular spillovers of other bat viruses, including Hendra and Ebola viruses.

Assessing Environmental Factors within the One Health Approach

“…The surveillance of terrestrial and aquatic ecosystems are of increasing interest and relevance in the One Health approach, as knowledge of the ecology of organisms can help to model and predict recurrent threats. Examples include, but are not limited to, blooms of toxic algae and outbreaks of infections spilling out from wildlife like bats, to humans [ 72 , 73 ]. In these examples, the environmental expertise can support the epidemiological modelling by identifying relevant modulating factors, such as pollution and land use for algal blooms, and bat-borne infection, respectively.…”

Ecological countermeasures for preventing zoonotic disease outbreaks: when ecological restoration is a human health imperative

“…In Bangladesh, bats (Pteropus medius) visit silver date palm trees (Phoenix sylvestris) tapped for sap collection. Bats lick the shaved area of the tree and sometimes urinate or defecate in the collection pots, contaminating the sap with Nipah virus (Luby et al 2006;McKee et al 2020). Although covering sap containers has reduced disease risk (Nahar et al 2013), the ideal solution would be an ecological countermeasure that draws bat populations to food resources not shared with people (Mckee et al 2020).…”

SARS-CoV-2: Cross-scale Insights from Ecology and Evolution

“…Concepts and tools from spatial ecology allow us to identify and predict landscapes at high risk of experiencing cross-species spillover [46]. In particular, anthropogenic landscape changes increase spillover risk by: (i) altering the abundance and distribution of wildlife hosts, with highly modified areas potentially attracting a greater abundance of known reservoir hosts of zoonoses (e.g., rodents and some bat species), (ii) promoting stress-induced shedding and host susceptibility, and (iii) increasing contact rates among domestic animals, wildlife, and humans [1,2,11,22,47].…”