Biology

The pangolin, the source of the Wuhan SARS-CoV-2 coronavirus?

Every third Saturday in February, International Pangolin Day is commemorated , sadly? famous in recent weeks because it appears that the pangolin is the reservoir of the Wuhan coronavirus (although it is still pending confirmation).

And if I sadly put between question marks it is because perhaps it is time to focus on this species that is in danger of extinction precisely because of illegal hunting for consumption as a delicacy in countries like China and Vietnam , or for use in medicine. traditional Chinese or for its curious skin based on scales.

Precisely, the consumption of its meat that was the traditional objective of hunting pangolins may be the origin of the infection by the Wuhan coronavirus or SARS-CoV-2 as its official name is, as has been recently declared. The disease has been called COVID-19.

A species is considered a reservoir of a pathogenic agent (it can be a virus, bacteria or parasite) when it has it in its body and in a natural and habitual way this species is not affected (or it affects it very little). to other species, in this case the human. Briefly, it can be said that a reservoir species is the natural host species of the pathogen.

A recent study published in Nature pointed out that the genetic sequence of a coronavirus found in pangolins matched 99% with that found in humans affected by SARS-CoV-2. It appears that pangolins have a good chance of being the source of this new virus.

Until February 7, no relationship with the coronavirus had been made public and it was still thought that given the similarities with the bat coronaviruses they could come from there since in the inventory of products that were made from the Wuhan market it does not appear in no time the pangolin. It is possible that it was on the market but it did not appear because the pangolin trade is illegal. This can make further investigations and controls difficult.

What are pangolins?

Despite their reptilian appearance, pangolins are mammals with scale-based skin. If from childhood we were told that one of the characteristics of mammals was that they were covered with hair, the pangolin is a clear exception to this rule. This is biology , full of exceptions.

pangolin
pangolin

Pangolins are mammals that fall within the order Pholidota, which is characterized by being mammals with skin covered with scales. Not to be confused with armadillos that belong to another order because their body is covered with juxtaposed bone structures but not scales.

This order contains six families, all of them extinct except for the Manidae family, which is where current pangolins are classified. There is only one genus with eight living species of pangolin, the genus Manis .

  • Manis crassicaudata  – Indian pangolin or Indian pangolin (Asia)
  • Manis pentadactyla  – Chinese pangolin (Asia)
  • Manis javanica  – Malayan Pangolin (Asia)
  • Manis culionensis  – Philippine pangolin (Asia)
  • Manis temminckii  – Temminck’s pangolin or terrestrial pangolin (Africa)
  • Manis gigantea  – Giant pangolin (Africa)
  • Manis tetradactyla  (or  Manis longicaudata ) – Long-tailed or black-bellied pangolin (Africa)
  • Manis tricuspis  – Arboreal pangolin or arboreal or white-bellied pangolin (Africa)

They live in tropical areas of Asia and Africa where they feed on ants and termites. They lack teeth but do have a very long tongue and powerful claws to be able to dig the nests of termites and ants and feed on them. They also allow them to dig into the ground to create burrows and hide in them.

This ability to excavate allows them to aerate the soil and facilitate the mixing of nutrients, thereby fulfilling a very important ecological function for soil conservation. In addition, as they feed on insects (they can eat up to 70 million ants a year) they regulate their populations and prevent pests.

They are nocturnal and solitary so that they only live alone or pairs. They are viviparous (that is, the female has the young inside the body until its full development) and only have one young at a time. When threatened they are able to roll up into a ball to protect themselves with their skin from scales.

Why are they threatened?

The eight species of pangolin are classified as “Critically Endangered” in the Red List of Threatened Species of the IUCN (International Union for Conservation of Nature) and according to data from the CITES convention it is the most trafficked mammal in the world, since 2015 As of 2019, 46 tons of scales were seized in importing countries, and more than 1,500 individuals between living and dead; as well as medicines, skins, etc.

Pangolins are highly prized for their meat in China and Asian countries where it is considered an exquisite delicacy . In traditional Chinese medicine its scales are thought to have properties as diverse as reducing swelling and improving circulation and for rheumatism, arthritis or asthma. In the fashion industry its scales were also highly valued.

In addition to the illegal hunting of these species, their habitat is threatened by its destruction to change land uses. This, together with the fact that they only give birth to one calf at a time, make it seriously threatened.

Asia’s pangolin populations are severely decimated by illegal trade, so the pressure has shifted to Africa where until now their illegal hunting was much less than in the Asian area.

Related Articles

Leave a Reply

Your email address will not be published.

Back to top button