World

COVID-19: The endless search for the origin of the virus | News about the coronavirus pandemic


Even as COVID-19 enters its third year as a pandemic, the world still won’t know the source of the virus that caused it all.

Just six weeks after declaring a global health emergency, the World Health Organization (WHO) declared the spread of the new coronavirus a pandemic. March 11, 2020.

But while the animal hosts of the coronaviruses that caused the 2003-2004 SARS-2004 and 2012 MERS outbreaks had been identified within months, the source of the current SARS-CoV-2 virus – along with its numerous mutations and variants. it – proven harder to grasp.

Last September, a task force set up by The Lancet COVID-19 Committee to search for the ultimate source of the pandemic was disbanded after 14 months, amid mastermind, reassigned and worry about conflict of interest. And the investigation by WHO, a public health agency with no authority to investigate, has largely stalled after tightly controlled fact-finding trip to China in January 2021.

China has yet to provide WHO with evidence to support Beijing’s assertion that the spread of the coronavirus has a natural zoonotic route – moving from bats to animal hosts to humans – and Huanan Seafood Market where the first cases were traced was quickly disinfected and closed.

The struggle to find the source has helped give more confidence about the possibility that the virus may have come from elsewhere, including leak lab. Either way, the evidence is still in China.

“I believe that China is not transparent; Colin Butler, professor emeritus of the National Center for Epidemiology and Population Health at the Australian National University in Canberra.

Plainclothes security officials guard the Huanan market, tied behind blue plastic panels, during the WHO expert team's visit to Wuhan in January 2021
A team of WHO experts visited Wuhan under strict conditions in January 2021. Huanan Market was cleaned and disinfected quickly after the first cases were identified in the central central city. China, complicating the search for the source of the virus [File: Thomas Peter/Reuters]

Late last year, Butler was commissioned by the United Nations Environment Program to write a report titled Environmental Change and COVID-19: The Risk of Future Pandemics in Asia and the Pacific. In the study, Butler listed medical and laboratory procedures as risk factors that could allow the virus to escape a controlled environment and spread widely. For example, China allows coronavirus experiments in places with low biosecurity, requiring only protective gear for lab staff, sinks and eyewash stations.

Remember that the origin of a In 1979 there was an anthrax outbreak in the former Soviet Union that killed at least 66 people was only revealed after the country’s collapse in 1992, Butler said that he believes the truth about the current pandemic will still be buried by the current Chinese leadership. .

“China will not be open about this under the current regime,” he said.

‘Standing to one side’

In the first months of the pandemic, in April 2020, Australia was one of the first countries to call for an independent inquiry into the origins of COVID-19. But other countries, especially the United States, did not echo Canberra’s call.

Butler added: “I completely believe that many people are not transparent enough – not only in China but also in the US.

In the US, molecular biologist Alina Chan shares Butler’s doubts.

Chan, a scientific adviser at MIT and Harvard’s Broad Institute, was one of the first scientists to advocate dismissing a lab leak as the source of the virus.

A civet cat in a chicken cage is watched by Chinese police after the animal was identified as a possible vector of SARS virus in 2003.
The animal hosts of the SARS virus nearly 20 years ago were identified within a few months [File: AFP]

Last November, along with British science writer Matt Ridley, Chan co-authored Viral: The Search for The Origin of COVID-19 and explained the evidence for two stories that most likely originated the virus. : through an animal carrier in the wild or a laboratory accident.

In a poll last summer, a majority of Americans, regardless of political conviction, said they believe the virus came from a lab leak in China. Even so, Chan said pushing for an investigation has been stymied by partisan politics in Washington.

Chan told Al Jazeera: “Everyone is taking one side and trying to take the other side down. “It is not an illusion to say that there is a cover-up.”

For Chan and all those who argue that the SARS-CoV-2 virus could have originated in the laboratory, as long as an intermediate host for the transmission of the virus from bats to humans cannot be identified, the scenario is unscientific natural origin. support it needs.

In addition, the widely shared observation that since its inception, the virus has had unique characteristics that make it extremely well-adapted to infect humans in bulk, continues to make it difficult for even humans to survive. coronavirus expert.

“Concrete evidence for the natural origin of SARS1 and MERS was quickly found despite less advanced technologies at the time. However, for SARS2, we were still unable to find any infected animals that might have passed the virus to humans at the market, and we have not obtained evidence to tell us when and how the virus was transmitted. stop spreading in Wuhan before mid-December 2019,” said Chan.

High-rise, crowded apartments in Shanghai are locked down with some people going to the rooftops to enjoy the fresh air
China is currently grappling with its worst COVID-19 outbreak since cases were initially identified in Wuhan with millions confined to their homes in Shanghai. [Hector Retamal/AFP]

Last month, new studies – among the most detailed published on the origins of the virus to date – identified the market as the “clear epicenter” of the pandemic based on the nature and grouping of the virus. of cases.

One of the papers, pending peer review, suggested that the earliest known COVID-19 cases were located near Huanan and that in November 2019 the virus had spread from bats to mammals. other and are spread in the western corner of the market, where live animals are kept and sold.

Virologist Marion Koopmansa member of the WHO expert team who visited China, said study led by Michael Worobey of the University of Arizona’s Department of Ecology and Evolutionary Biology, provided “compelling evidence” that the market is indeed where it all started.

But Chan and other scientists say the papers made claims based on incomplete data and misleading samples. And for scientists tracing how the virus spread – especially in the early days – the scarcity of data provided by China has proved particularly difficult.

Evolutionary Risks

Hoping to trace the pandemic, last spring, virologist Jesse Bloom at the Fred Hutchinson Cancer Research Center in Seattle tried to find the genome sequence of SARS-CoV-2 from cases of coronavirus. earliest outside of China – only to find out data was removed from an open access website maintained by the US National Institutes of Health, at the request of Chinese researchers. As the owner of the data, scientists have the right to request its removal without giving a reason.

For example, Bloom said if the Wuhan Institute of Virology released its entire database of bat viruses, it would go a long way to solving the question of whether one of its labs is a bat virus. origin or not.

Without that information, he said the investigation could not be scientifically resolved. “It’s an important question to understand the origins of the pandemic,” Bloom said. “And the public wants a more scientific explanation.”

Earlier this month, Bloom and 17 other scientists signed a letter asking China to release sequencing data from samples taken at the market.

Regardless of whether the virus is transmitted by animals or by laboratoryRosemary McFarlane, assistant professor of public health at the University of Canberra, says a lot can be done to prevent the risk of the next outbreak.

That’s because both scenarios point to longstanding problems with how humans handle wildlife. Keeping them in close proximity during trade and transport increases the potential for the virus to spread between animals and to humans.

“We can continue to debate the origins of this pandemic, but we need to understand what the risks are now, as the virus circulates among people with low access to vaccines and those with limited access to vaccines. near animals. All of these create opportunities for virus evolution, McFarlane said. This pandemic “is a wake-up call to the possibility of future mishaps”.



Source link

news7d

News 7D: Update the world's latest breaking news online of the day, breaking news, politics, society today, international mainstream news .Updated news 24/7: Entertainment, Sports...at the World everyday world. Hot news, images, video clips that are updated quickly and reliably

Related Articles

Leave a Reply

Your email address will not be published.

Back to top button