Covid-19 – a blessing for pangolins?

Covid-19 is a human disaster. However, for one group of animals, there may be a silver lining. Pangolins are one of the most heavily trafficked animals in the world, and as a result they are endangered. But in the past few weeks they have been linked to the initial outbreak of the Covid-19 disease in China. The evidence is inconclusive, but it has already prompted the Chinese government to take action. If more actions against the wildlife trade follow, the incident could prove to be a turning point for pangolin conservation.

A key question is where Covid-19 came from. Many animals carry coronaviruses and are potential sources of infection. That is important to know, if only because it should help us prevent future outbreaks. Several ideas have been proposed, but arguably the most dramatic is that pangolins were the source.

World’s most trafficked mammal
Pangolins look like scaly anteaters. Uniquely among mammals, their bodies are covered in hard protective scales made of keratin: the same material as our nails. They feed on insects such as ants and termites, and are often nocturnal and shy. While they look like anteaters, they are not closely related to them, and their closest living relatives are actually carnivorans: the group that includes wolves and cats.

There are eight species of pangolin. Four live in Africa and four in Asia. All are at risk of extinction, according to the International Union for Conservation of Nature (IUCN). Two of the African species are considered vulnerable and two are endangered. Of the Asian species, one is endangered while the other three are critically endangered.
Pangolins are illegally hunted and traded for two main reasons. First, their meat is considered a delicacy in several south-east Asian countries, especially China and Vietnam. And second, their scales are used in Chinese traditional medicine. As a result, they are the world’s most trafficked mammals.
The idea that pangolins gave us Covid-19 emerged at a press conference given by the South China Agricultural University in Guangzhou on 7 February. Two scientists there, Yongyi Shen and Lihua Xiao, were said to have compared coronaviruses from pangolins and from humans infected in the outbreak. The viruses’ genetic sequences were said to be 99% similar. One co-author, Wu Chen of Guangzhou Zoo, had previously helped show that Sunda pangolins carry coronaviruses.
However, the results had not been published at that stage, so other scientists could not examine them in detail. Meanwhile, there were many other possibilities. The virus could have come from an animal and seafood market in Wuhan, where many species were held. Animals in such markets are often kept in closely packed, unsanitary conditions, with many people nearby: a perfect opportunity for a virus to jump species. Many pointed the finger at bats: the virus is genetically similar to those in bats, and it would not be the first time a disease passed from bats to humans. There was also a study linking the virus to one found in snakes, but this is now considered unlikely.
Then there was a twist in the story. On 20 February the researchers posted a preliminary version of the study on the preprint site bioRxiv. The conclusions were radically different to what was described at the press conference. While the pangolin virus was “genetically related” to the one infecting humans, it was “unlikely to be directly linked to the outbreak because of the substantial sequence differences”. The 99% similarity was only in one region of the genome. Across the entire genome, the similarity was only 90.3%. There had been an “embarrassing miscommunication between the bioinformatics group and the lab group of the study”. When contacted by the Observer, Xiao declined to comment.

A halt to the wildlife trade?
However, the Chinese government was already lurching into action. On 24 February, China announced an immediate ban on trading and eating many wild animals, including pangolins. Officials began shutting down wild animal markets across the country.
This was the latest in a series of steps that ought to reduce the pangolin trade. Back in 2016, the international trade in pangolins was entirely banned by the 183 nations that signed up to the Convention on the International Trade in Endangered Species (Cites). All eight pangolin species were placed in Appendix I of the Convention, giving them the strictest protection currently possible.

However, so far this does not seem to have resulted in a drop in the number of pangolins traded, says Xu Ling, China director at wildlife trade monitoring group Traffic. The trade continues but the nature of the shipments has changed. “Before 2016 we could find frozen pangolin bodies, the meat smuggled in from other parts of south-east Asia to China,” says Ling. Nowadays most shipments are purely pangolin scales. Often they come from Africa, after being illicitly shipped out via Nigeria.

More recently, in August 2019, China’s state insurance providers announced that they would stop covering medicines made from pangolin scales. The move took effect in January 2020.

Against this background, it is unclear what impact China’s new ban on eating wild meat will have on pangolins. “Even without this ban, pangolin meat consumption was forbidden in China,” says Ling, as pangolins had protected status. This was reflected in the shift to importing scales. These are only legal if they come from certified sources but, as so often happens, the traders find ways around that. In the longer term, the loss of insurance funding may undercut the scale market.