Since the beginning of the year, the whole world has been monitoring the development of the situation in China in connection with the outbreak of the new coronavirus 2019-nCov. Every day from the Celestial Empire, new data are received on the number of infected, which is constantly growing. Scientists have found that the coronavirus can be transmitted from person to person at the stage of the incubation period - that is, before the first symptoms appear, which significantly complicates an already difficult situation. Meanwhile, researchers are trying to understand the origin of 2019-nCov. At the moment, there are two hypotheses: a gradual mutation of the virus among wild animals on the market in Wuhan and a leak from a laboratory for the study of deadly viruses, which is located near the epicenter of the outbreak.
Where do new viruses come from in the 21st century?
The emergence of new viruses today should not surprise anyone - after all, viruses, like all organisms on our planet, develop and adapt to new conditions. Due to the growth of the world's population and the amount of meat consumed, a variety of viruses have received carte blanche in their hands: a large concentration of mammals and poultry on farms where sanitary standards are not always observed, becomes an ideal breeding ground for viruses. At least that was the case with bird flu and swine flu. Avian influenza is an extremely common bird disease in the wild, but when this strain gets into domestic chickens, they die rather quickly due to lack of immunity. And the frequent contact of sick birds with humans gradually allows the virus to mutate, which was the reason for the emergence of a lethal strain of bird flu for humans.
A similar situation was observed during the outbreak of severe acute respiratory syndrome (SARS) in 2003: the carriers of the virus were bats that live in a cave in Yunnan province in China. In general, bats do not get sick with anything. So, recently we told you about the threat of a pandemic of the Nipah virus, which is carried by fruit bats of the genus Pteropodidae. The rise in temperatures due to climate change is also a threat to the spread of other equally dangerous diseases.
In such conditions, animals were kept at the seafood market in Wuhan.
The genome of 2019-nCov, as scientists have found, almost 80% coincides with the genome of SARS. However, the death rate from SARS was significantly higher than from the new coronavirus. But if bats were the cause of SARS, where did the 2019-nCov come from in the Wuhan seafood market? Scientists have narrowed down the reasons for the spread of the coronavirus to interspecies transmission from bats or snakes and a potential laboratory leak in Wuhan, CNN reports.
Promotional video:
Reason # 1: Transmission of 2019-NCoV to Bat Snakes
Given the causes of SARS and MERS, it is not surprising that the first suspicion of scientists fell on bats. Subsequently, it became known that at the seafood market in Wuhan, live wild animals were traded, which the citizens of the Celestial Empire often use for culinary purposes. So, the researchers suggested that the coronavirus was transmitted from bats to snakes and, ultimately, to humans. Chinese food cravings, including bat soup, have been heavily criticized lately on social media. In 2017, Wang Mengyun, a Chinese celebrity, apologized after a video of her eating a fried bat went viral. The question of whether the coronavirus or other forms of the virus can be transmitted to humans after heat treatment remains open.
Bat soup on the left. On the right, Chinese actress Wang Mengyun is eating a fried bat. As the researchers write in a paper published in the Journal of Medical Virology, snakes are the most likely reservoir for 2019-nCoV. Despite the criticism of this work in the scientific community, experts believe that finding a large number of wild animals in cages on the market in Wuhan represents ideal conditions for the reproduction and interspecies mutation of viruses. Previous studies have shown that the virus can spread from live bats in poorly regulated markets where live animals are traded.
Reason # 2: Potential Leak from the Deadly Virus Lab
In 2017, the National Biosafety Laboratory was opened in Wuhan to study the world's most powerful viruses and pathogens. However, even then, researchers expressed concern about a possible leak from the laboratory. Due to the fact that in Chinese laboratories, scientists are testing pathogens on animals, including monkeys, there is a possibility that pathogens can break out in various ways. According to some experts, due to pathogens, monkeys can exhibit variable behavior.
Pictured is the province of Hubei. The distance from the seafood market to the virus laboratory is marked in red.
They can run away, scratch, bite. However, based on the development of the virus and research in recent weeks, interspecies transmission from bats or snakes to humans is a more likely cause of the coronavirus than a possible leak from an object. However, the version of a leak from the laboratory cannot be completely ruled out. So, in 2004, a SARS leak occurred in one of the laboratories in China.
Lyubov Sokovikova