COVID-19 and bats

Research papers about Coronavirus Disease (COVID-19) and the virus that causes it (SARS-CoV-2) are being produced at an unprecedented rate and this information will be updated annually or when a new breakthrough is announced.

Coronaviruses are a large family (the Coronoviridae) of viruses. Humans and many other animals carry a wide range of coronaviruses, many of which are not seriously harmful, for example the common cold is a coronavirus. However, they include a small number of very serious respiratory viruses, including SARS-CoV-2, the virus that is causing the coronavirus disease (COVID-19) pandemic.

COVID-19 is a human disease with animal origin- a zoonotic disease. While the animal source of SARS-CoV-2, the virus behind the COVID-19 pandemic, remains unproven, the genomic sequence of SARS-CoV-2 has offered a means of testing whether natural evolution or a laboratory-origin is most probable. Scientific data collected in the last 5 years by virologists worldwide supports a direct zoonotic natural origin (14). It is most likely to have an ancestral evolutionary origin in a bat species many years ago, and to have reached humans through an intermediary animal species. Once in humans, it mutated to be able to spread between well people. It is important to note that spread of COVID-19 is from person-to-person.

No, the virus that causes COVID-19 hasn’t been isolated from any of the UK’s 17 resident breeding bat species, nor any bat globally. There are no known zoonotic (harmful to humans) coronaviruses found in UK bats. In fact the COVID-19 virus hasn’t been isolated from any of the world’s 1465+ species of bat. A coronavirus with 96% of its genome in common with SARS-CoV-2 (2) has been found in a single species of bat (Rhinolophus affinis) in China. This may sound significant, but to put it in context, we share 96% of our genome with chimpanzees but we are not the same species. It is important to stress that it is humans that transmit COVID-19 to other humans. Bats do not carry COVID-19 and you cannot catch COVID-19 from a bat.

Zoonotic spillover is the transmission of a pathogen from an animal to a human, often through an intermediary species. For such an event to happen, zoonotic pathogens must overcome a series of barriers that would otherwise prevent spillover infections into humans (5). If we fail to care for the natural world and all of the services that it provides to humanity then ecosystems can break down in ways that have significant impacts on us, including through emerging infectious diseases (6).

Human alterations to the environment can therefore break or even remove some of these barriers (7). For example destruction of natural habitat by deforestation and subsequent intensive livestock farming on the cleared land. This process brings wildlife into closer contact with humans and livestock than would naturally happen, providing the opportunity for a spillover event.

Interfaces that can provide opportunities for spillover include the live wildlife trade, in which many different species of wild animals are brought together in markets, can also provide the conditions for spillover events. The traded animals are held in cramped, stressful, unsanitary conditions, with many different species caged side by side and slaughtered to order. The species in these markets would not be found together in such close proximity in the wild. Such trade increases the chances that viruses can jump from one species to another, and ultimately from animals to humans.

BCT has joined with more than 240 other organisations from around the globe to call for the World Health Organisation (WHO) to recommend that governments worldwide ban wildlife markets and the use of wildlife in traditional medicine. You can read the letter to WHO via our News pages.

Kit Stoner, BCT’s Chief Executive Officer, states “The selling of live wild animals in markets is both cruel and facilitates the spread of viruses by bringing stressed animals of different species into close proximity where this would not naturally occur. Wildlife markets pose an increasing risk to human health and a danger to the conservation of bats and other wildlife. Bat Conservation Trust recognises the need to take urgent action which is why we have joined this broad coalition of organisations demanding governments ban wildlife markets.”

Dr Kevin Olival, of EcoHealth Alliance, points to closing and cleaning up wildlife markets as a win-win solution in a National Geographic article: “One intervention, which is fairly simple, is reducing the wildlife trade and cleaning up the wildlife markets. Cutting back the wildlife trade has a win-win effect of both protecting species that are harvested from the wild and of reducing spillover of new viruses”(10). There is a widespread recognition that along with banning wildlife markets there is a need for initiatives that both educate people and provide those dependent on this type of trade with alternative sources of income and protein in order to further reduce the risk to human health.

No, the pandemic was caused by people. Human activities that alter the environment can increase the risk of disease spillovers from wildlife to people (a zoonotic spillover is the transmission of a pathogen from an animal to a human). The science writer, David Quammen, who has published two books on wildlife and diseases, wrote about this back in January (9). He argues that we specifically made this pandemic (or epidemic as it was then) by engaging in unsustainable ecological destruction and the dangerous and devastating trafficking and illegal trade of wildlife for human consumption.

Deforestation and subsequent intensive livestock farming on the cleared land will bring wildlife into much closer contact with humans and livestock than would naturally happen, providing the opportunity for a spillover event. Opening up roads through pristine rainforest increases access for hunting. The live wildlife trade, in which many different species of wild animals are brought together in markets provide conditions for spillover events. The traded animals are held in cramped, stressful, unsanitary conditions, with many different species caged side by side and slaughtered to order. The species in these markets would not be found together in such close proximity in the wild. Such trade increases the chances that viruses can jump from one species to another, and ultimately from animals to humans.

No, culling bats will not end the COVID-19 pandemic or any future emerging infectious disease outbreaks, in fact this may well increase the dangers since stressed animals may become more disease prone. It is human activity that led to the current pandemic and it will be changing human behaviour in relation to wildlife that may prevent future pandemics. To prevent future outbreaks we need to stop uncontrolled habitat destruction and control the trade in wild animals. See ‘How did COVID-19 get from wildlife to people?’ above.

There are over 1,400 bat species around the world (of which 17 are resident and breeding in the UK). Many have adapted to living alongside us in both urban and rural environments, in our gardens, parks and even roosting around our homes, without posing a threat to their human neighbours.

Many bat species are in trouble and need our help to survive. Some bat species have legal protection (all do here in the UK) but globally many don’t and much more needs to be done to ensure the survival of bats and other wildlife around the world. While the killing of bats will not have any effects on the spread of COVID-19, it would adversely affect the conservation of bat populations and the benefits they bring to people and our ecosystems. Bats provide enormous benefits including pollination, seed dispersal and pest control, worth billions of dollars annually. (See the BCT news item ‘What have bats ever done for us’ for more information.)

The Secretariats of the Convention on the Conservation of Migratory Species of Wild Animals, the Agreement on the Conservation of Populations of European Bats and the Agreement on the Conservation of African-Eurasian Migratory Waterbirds have issued a statement of facts relating to bats and COVID-19.

There’s no evidence that bats in the UK carry any coronaviruses that can be passed to humans but can humans pass the COVID-19 virus to animals? There have been a small number of cases where dogs, cats (both domestic pets and big cats in a zoo), and mink have tested positive for the virus following close contact with their owners/handlers, who were known or suspected to have had COVID-19 (11). None of these cases were in the UK.

We don’t yet know whether humans can pass the COVID-19 virus to animals in the wild. So, for the bat’s protection, if you’ve found a grounded or injured bat we’d recommend that you cover your nose and mouth when you have to get near to the bat to contain it. It doesn’t have to be a proper face mask – you can use a tea towel or T-shirt. Please see our advice pages if you find a bat.

COVID-19 transmission is most likely when people are in close proximity to each other (hence the social distancing guidelines). If you are lucky enough to have a bat roost in your house or bats visiting your garden they have nothing to fear from you as there will not be that level of close proximity (and you have nothing to fear from them, see: Do the bats in my house have COVID-19? / Can I get COVID-19 from the bats in my house? above). You do not need to take any extra precautions unless you find a grounded bat that needs help.

As they will regularly be in close contact with bats, we are asking that bat rehabilitators take precautions just as they would for other disease transmission, to wear gloves (you should not handle bats with bare hands), minimise handling, practice good hygiene with food and housing, etc. along with additional precautions specific to this disease, including wearing a face covering as a precautionary measure to minimise any potential risk there might be.

You should not care for an animal if you are poorly yourself or think you might have COVID-19. For information about risks associated with pets, please see the World Organisation for Animal Health (OIE) website (the animal equivalent of the World Health Organisation).

A small number of bats in the UK have been found to carry rabies viruses called European Bat Lyssaviruses (EBLV); but these are from a completely different viral group to the virus that causes COVID-19.

There are two known rabies viruses found in the UK: EBLV-1 and EBLV-2 (these are not the same as the classical rabies virus, which has never been found in a bat in Europe). Rabies caused by infection with EBLV has only been associated with one human case in the UK and EBLVs have only been found in a small number of bats despite more than 15,000 bats having been tested by the Animal & Plant Health Agency since 1986. EBLVs are transmitted via a bite or scratch therefore there is no risk if you do not handle bats. If you do need to handle a bat (i.e. if it is grounded/injured) wear gloves to protect yourself from any potential risk. It is always good practice to wear gloves when handling wild animals anyway (12). For more information please see our web pages about bats and rabies and what to do if you find a grounded bat. No other zoonotic diseases have been found in UK bats.

No, bats don’t host any more disease-causing (zoonotic) viruses than any other groups of animals (mammals and birds) of similar species diversity (13). There are more than 1,400 different bat species, the second largest group of mammals by species. Taken as a group, bats are considered ‘reservoirs’ (long-term hosts) of a number of viruses but most of these are not harmful and cannot be passed to humans.

There is a lot of misinformation circulating around the COVID-19 pandemic. It is really important that people check the facts behind the stories they see in the media or via social media platforms.

There are excellent fact checking websites, including Full Fact UK, Snopes, etc., the COVID-19 specific Misinformation Watch and Coronavirus: the science explained (focussed on human health), and more generally the FAIR website provides guidance on how to detect bias in the news media.

1. Wu et al (2020) A new coronavirus associated with human respiratory disease in China. Nature 579, 265-269
2. Zhou et al (2020) A pneumonia outbreak associated with a new coronavirus of probable bat origin. Nature 579, 270-273
3. Andersen et al (2020) The proximal origin of SARS-CoV-2. Nature Medicine 26, 450–452
4. Lam et al (2020) Identifying SARS-CoV-2 related coronaviruses in Malayan pangolins. Nature (pre-publication).
5. Plowright et al (2017) Pathways to zoonotic spillover. Nature Reviews Microbiology 15, 502–510
6. Robins (2012) The Ecology of Disease. The New York Times
7. Contagion. Steven Soderbergh. Warner Brothers. 2011
8. Lindahl & Grace (2015) The consequences of human actions on risks for infectious diseases: a review. Infection Ecology & Epidemiology 5, 1
9. Quammen (2020) We Made the Coronavirus Epidemic. The New York Times
10. Akpan (2020) New coronavirus can spread between humans—but it started in a wildlife market. National Geographic
11. World Organisation for Animal Health (2020) Questions and answers on the COVID-19
12. RSPCA (2020) What to do with injured animals.
13. Mollentze & Streicker (2020) Viral zoonotic risk is homogenous among taxonomic orders of mammalian and avian reservoir hosts. Proceedings of the National Academy of Sciences
14. Alwine JC,Casadevall A, Enquist LW,Goodrum FD, Imperiale MJ. 2023. A Critical Analysis of the Evidence for the SARS-CoV-2 Origin Hypotheses. mSphere8:e00119-23.https://doi.org/10.1128/mspher...