This time five years ago, the virus that caused Covid-19 was spreading all over the world without deterrence. One of the biggest questions that remain: Where did it come from?
Today, increasing evidence from more than ten studies indicates a person, or people, hunting the virus from an animal or wild animals in the seafood market in Huanan in Wuhan, China, the city at the center of the disease. And the animal in the upper part of the list is the Raccon Dog (NYCteteuts Procyonoides).
“There is a great focus on the raccoon dogs,” says Christian Andersen, an evolutionary biologist at Scripps Research in La Jolla, California.
Some scientists, including the virus scientist Edward Holmes of Sydney University in Australia, suspected of raccoon dogs all the time. On January 21, 2020, he sent an email to Andersen and another colleague, with the topic “Booker Booker”. In Jest, suggest a bet on the animal that may carry the virus for people. He said: “I bet on the raccoon dog.” Holmes watched the raccoon dogs in the Huanan market when he traveled to Wuhan in 2014.
But part of the reason that the raccoon dogs topped the list of suspects because they were studied more than other animals, including those also in the market, says Michael Warbob, the evolutionary biologist at the University of Arizona in Toxon. He says there are more possible candidates.
Marion Kobmans, the virus of Erasmus MM in Rotterdam, agrees to the Netherlands. “We must be modest about our ability to predict animal species,” she says.
The origin of the epidemic is still deeply foresight, and the lack of clear answers did not help. The virus may arose into the bats that live in southern China. From there, many scientists believe that he had an intermediate animal transferred to people. The virus could have passed directly from the bats, although this is considered less likely to give his homeland far from Wuhan. Some still suggest that the virus could have escaped, or was deliberately launched, from the Wuhan Institute of Virus, which was known to have research on crown viruses.
The viral host
One of the reasons that the raccoon dogs as a major candidate is early is that they may have been involved in passing another virus, associated with people. In 2003, the researchers isolated matches close to the virus that causes acute breathing syndrome (SARS) in many custodians and a raccoon dog in a living animal market in Guangdong, China.
This discovery prompted researchers in Germany to investigate the ability of these animals to SARS-COV-21.
They found that the raccoon dogs could develop SARS-COV-2, and despite the lack of patients themselves-the infection can be transmitted to other animals.
Holmes and colleagues’ studies also showed that the crushed and wild dogs in China are often affected by many viruses that can jump between species. “Raccon dogs are very popular hosts,” says Holmes.
The right time, the right place
It included many first cases of Covid-19 market, which indicates that it was the Firvalover website. SARS-COV-2 sequence of the first injured people, in late December 2019 and early January 2020, as well as geographical location and epidemic data, support this2.
During the fascism, the market was closed by the authorities, but the researchers know that the raccoon dogs were being sold there, for their parts and as food. In June 2021, the study of the results of the monthly surveys of lively wild animals that are sold across four markets in Wuhan between May 2017 and November 2019, including seven kiosks in Huanan3. Every month, 38 raccoon dogs have been sold in these markets. The most selling species were Amur (Erinaceus amurensisOn average 332 individuals per month. Civet Palm Civeet (convincing (Pagoma Lervata), Swazine Grill (Arctonyx AlbogularisChinese bamboo mice (Sinensis roots) And Porcupines Malayan (Hystrix BrachyuraIt was also sold regularly.
December 2019 sales records from the Huanan market also list the trading of live animals or products of bamboo mice, gynecasis, and ends, among other things.
The additional evidence to support the theory of Daccoon-Dog came in 2023. The Chinese researchers published genetic data from the swabs that were taken in the Huanan Market in January 2020, after its closure, including stalls, garbage and sanitation boxes4. DNA studies of mitochondria of raccoon dogs found in many glimpses, including those that have proven positive for SARS-COV-2. Backer’s raccoon dogs (Pruinosus rootsThe most common types of wildlife were in mammals that were discovered in the DNA of mitochondria; Cvets and Hog Badges are found, but not in many samples5. The results do not prove that animals have SARS-COV-2, but if they have it, this is the type of evidence that you expect to find, says Andersen.
The unpublished work written by Angela Rasmussen, the world of viruses at the University of Saskatchewan in Saaskaton, Canada, indicates that some of the raccoon dogs and the largest pigs of the pigs (Arctonyx collarOn the market, it may have been sick, although it is not clear what the virus was infected with it.
Other animals on the market, which could have been infected with the virus and may have been transferred to people, include bamboo mice, Malayan isotopes, and Amur. But researchers do not know how much these types are offered to SARS-COV-2 infection.
Cellular studies indicate that the Himalayan palm clients can be infected with the virus, but whether they can transfer the virus to other animals that have not been studied, partly because these studies are expensive and were not a priority early in the epidemic.