By: Laura Pulscher, MSc, PhD
A study recently published in Transboundary and Emerging Diseases by postdoctoral fellow Laura Pulscher, PhD, MSc and colleagues explores the ability for small, geographically isolated bat populations to maintain multiple viral families. The strategies
for viral maintenance in bat populations is not well understood, some viruses may require large populations for sustained transmission while others may establish persistent infections which could be sustained in smaller, isolated populations. Using
the Christmas Island flying-fox (Pteropus natalis), a medium-sized fruit bat confined to Christmas Island, as a model species, Pulscher and colleagues sought to determine if paramyxoviruses, coronaviruses, and a rabies-related virus, Australian bat
lyssavirus, could be maintained in this small, geographically isolated bat population.
Serological data provided evidence that the Christmas Island flying-fox is maintaining a pararubulavirus and a betacoronavirus, but not henipaviruses, Menangle virus, or Australian bat lyssavirus. This study provides further support that these viruses
can be maintained in isolated populations likely through latent infection or rapidly weaning immunity resulting in re-infection of individuals within the population. From a One Health perspective, the apparent absence of some pathogens in this population
may make the Christmas Island flying-fox more susceptible to an introduced disease either due to spillover from humans (termed a reverse zoonoses) or due to the introduction of a non-native bat species, or other vector. Increased biosecurity protocols for ships docking on Christmas Island and increased use of personal
protective equipment by researchers and staff working with flying-foxes
is warranted.
Additionally, as the Christmas Island flying-fox is a critically endangered species, a conservation
breeding program is being considered as a possible management tool for the population and the presence of a pararubulavirus and betacoronavirus could have implications for public health. Further studies are needed before any risk can be assess; regardless,
people handling Christmas Island flying-foxes, and bat populations more broadly, should wear personal protective equipment to not only prevent viral spillover, but also reverse spillover events.
The full article can be found here.