Updated Sep 2024
Bats play a vital role in ecosystems around the world. They are a diverse group of animals accounting for over 20% of the world's mammals. Different species of bats contribute to wild and agro-ecosystems; pollinating plants, spreading seeds, and feeding on insects that threaten crops.
In the UK, changes to our bat populations can indicate changes in aspects of biodiversity. For example bats might suffer when there are problems with insect populations (because our bats feed on insects) or when habitats are destroyed or poorly managed (for example, some bats only live in large woodlands).
In addition to their important roles in many environments around the world, bats (like nearly all mammals), may carry microbes, including viruses, bacteria, or other parasites, that could potentially infect people. Different bat species in different regions generally host different microbes, and the distribution of potential pathogens may vary throughout the range of any given species.
A zoonosis is any disease or infection that is naturally transmissible from vertebrate animals (such as bats) to humans. While the risk of becoming infected with a bat-borne disease is generally low, the consequence (or impact) of the transmission of these pathogens can be very high. For example, Nipah virus in Southeast and South Asia and Marburg virus in sub-Saharan Africa, can have very high fatality rates and few to no available medical countermeasures. Some zoonoses, such as rabies ( which is the only zoonotic disease associated with bats in the UK), are 100% preventable through vaccination and other methods.
Transmission from wild animals to humans is normally the result of human alterations to the environment. For example with bats, destroying their habitat (by deforestation and intensive building for example) and the intensification of livestock farming, can mean that bats are forced to live more closely to humans, livestock and pets than they would naturally. This closer contact can result in cases of spillover of a virus into human populations either directly or via an intermediate host (e.g. livestock).
