Kozhikode: Recurring instances of Nipah outbreak in Kozhikode has brought the focus on the need for enhanced and regular surveillance of Nipah virus dynamics in bats (the main reservoirs of the virus) and there are questions whether ecological factors – including shift in cropping practices – have increased the chances of human-bat interactions and the risk of virus spillover.
Experts said regular virus surveillance in Pteropus medius species of large fruit-eating bats through cross sectional analysis must be prioritised to assess the risk of Nipah spillover as it will help target interventions to reduce the same. “Also, we should have mechanisms in place to monitor the population structure of bats to see if there was an increase in human-bat interactions,” said chief veterinary officer of forest department Dr Arun Zachariah.
He said that an integrated disease-ecology approach – which focuses on host-pathogen systems in context of their environment and evolution and how it affects patterns and processes of infectious diseases – is needed. He said this must be done by bringing various stakeholders together as it would help identify the factors behind the reemergence of the disease in the region.
Zachariah said there was a need to do an in-depth study into ecological changes and whether it had links with recurring outbreaks. “Shift in agri cropping practices is a major factor which should be looked into in detail. It has been observed that more bat habitats are found near human boundaries and agricultural fields than what is seen inside forests and such linkages should be examined closely,” he said.
Faculty at Kerala Veterinary and Animal Sciences University’s centre of wildlife studies Dr George Chandy said increased cultivation of fruit trees in home compounds could be a possible factor that attracts bats to human habitations and further research is needed to shed light on whether this was leading to increased human-bat interactions.
Chandy said that the pandemic made us adopt simple behaviour modifications like proper washing of hands that helped in preventing the spread of the disease and similarly awareness and adoption of simple measures like avoiding fruits bitten by bats and care while handling crops and fruits bitten by bats can help in preventing possible spillover of the virus to humans.