The pangolin - an endangered mammal with scales all over its body, and a long tongue that it uses to hunt ants - has now entered the COVID-19 scientific journals because it carries a coronavirus that looks strikingly similar to the virus that has swept the world.
In February a team of scientists at the South China Agricultural University took a sick pangolin into the lab. It not only tested positive for COVID-19, but some of the viral genes were close matches to the genes in the human version of the virus, and the “spike protein” which the virus uses to penetrate a cell was nearly identical.
How does an ant-eating, solitary hunter that inhabits remote wooded areas infect humans?
“Pangolins, even though most people have never heard of them, they are, in fact the most illegally trafficked wild mammals in the world, more than tigers, more than elephants, more than rhinos, anything,” said Paul Thomson, Director of Conservation Programs at Wildlife Conservation Network.
Pangolin meat is considered a delicacy in parts of Asia, and the animal’s scales are believed to have medicinal qualities. According to the Red List of Threatened Species, all eight species of pangolin are either vulnerable, endangered or critically endangered. But despite its protected status, a UN report released last month shows seizures of illegally traded pangolins have skyrocketed in the last ten years.
“Pangolins are being traded along with other illicit materials, firearms, narcotics, even human trafficking,” said Thomson.
One theory is the virus began its journey in a bat, jumped to a pangolin, and then found a host that would spread it worldwide and ultimately to humans.
“Bats are very interesting because they have like a super strong immune system - stronger than the human one, and so they harbor a lot of viruses because it just doesn't bother them,” said Julia Schaletzky, a biochemist at UC Berkeley. The bat would then shed the virus in its droppings. “This virus particularly is shed in the stool,” said Schaletzky, “it is one of the major elimination routes.” So, the bat’s droppings would carry the virus to the forest floor.
“Potentially a pangolin went rummaging through that leaf litter on the forest floor, foraging for termites or ants and ... picked up the scat from the bat and then took on that virus,” said Thomson.
In this scenario, the virus would have made the pangolin sick, but would never have left the forest. But, add a poacher and a worldwide trafficking network, and the dead, infected pangolin travels thousands of miles, landing in Asian markets as meat. Its scales are bagged up to be used in Chinese traditional medicine. A market in Wuhan, China remains high on the list of possible starting points for the COVID-19 pandemic.
In late February, as a response to the spreading disease, the Chinese government announced it was increasing penalties for the illegal wildlife trade, and stated “It is forbidden to eat terrestrial wild animals with important ecological, scientific and social value." The committee stopped short of a ban on medicinal use of wildlife, but vowed to strictly regulate the "non-edible use" of wild animals in a timely manner.
“Pangolin scales were used in Chinese medicine for over a thousand years,” said Lixin Huang, Vice President of China Projects at California Institute of Integral Studies. Even though scientific studies show pangolins scales have no healing effect, they continue to be used to treat a wide variety of ailments like circulation problems and malarial fever. Huang is leading the charge to replace pangolins with alternatives.
“As the world is changing, traditional medicines or the way how traditional medicines are practiced have to change,” said Huang, who is confident that herbs and minerals can successfully replace the pangolin - or any other endangered animal - in Chinese traditional medicine, pointing out that doctors across China have already moved away from using pangolins in treatments. “If you'll go to the hospital, the doctor would never prescribe pangolin in the formula for patients - but you find the products in the market,” she said.
Those markets continue to be supplied by a massive, worldwide trafficking network that continues to grow year to year, and is now considered a potential bad actor in the COVID-19 outbreak. But Thomson said, this isn’t the first time the illegal wildlife trade unleashed a dangerous disease.
“Some of the biggest, most damaging or high-risk diseases we've seen all stem from wild animals and either the trade or consumption of wild animals,” said Thomson. “We saw it with SARS, with Ebola, with MERS, and now we're seeing it with COVID-19. So this entire thing could have been prevented if we weren't consuming animals like pangolins.”