A qualitative risk assessment for re-introduction of rabies into rabies-free areas of Bhutan

Abstract

Background: Although, rabies is eliminated from most regions of Bhutan, it remains endemic in the Southern region and sporadic incursions are reported in the East. Elimination of rabies from these areas is challenged by the porous border with the neighboring states of India which facilitates free and unregulated movement of people and animals. Around 17 outbreaks of rabies are reported annually in dogs with spill over infection in other livestock species. This poses constant public health risks and economic loses to communities. Furthermore, due to anthropogenic factors such as increasing human settlements along highways, animal transportation, and the complex and changing human-pet relationship, there is a likelihood of reintroducing rabies to the rabies-free areas. Therefore, the objective of this study was to estimate the risk of rabies re-introduction and to identify the most effective risk mitigation options. Methods & Materials: The assessment was conducted for three risk pathways under scenarios in which the current risk mitigation measures were in place and in which no risk mitigation measures were in place. These were the pet dog pathway, stray dog pathway, and cattle pathway. The likelihood of an event occurring was assigned using the available literature. Where gaps in knowledge existed, expert opinion was used. Results: Under the scenario in which no risk mitigation measures were in place, the risk of rabies re-introduction to Bhutan was estimated to be medium for the stray dog pathway with a low level of uncertainty, low for pet dog pathway with a low level of uncertainty, and very low for the cattle pathway with a medium level of uncertainty. When current risk-mitigation measures were included, the risk of rabies reintroduction was estimated to be very low for the stray dog pathway with a medium level of uncertainty, low for pet dog pathway with a low level of uncertainty, and extremely low for the cattle pathway with a medium level of uncertainty. This reflects Bhutan's current effective rabies control program. Conclusion: The risk of rabies re-introduction through all the pathways was greater than negligible. The findings highlight the importance of maintaining and enhancing current risk mitigation measures to prevent re-introduction of rabies.