Bats in Laos caves found to carry coronaviruses that share key feature with Sars-CoV-2

‘Bats dwelling in limestone caves in northern Laos were found to carry coronaviruses that share a key feature with Sars-CoV-2, moving scientists closer to pinpointing the cause of Covid-19. Researchers at France's Pasteur Institute and the University of Laos looked for viruses similar to the one that causes Covid-19 among hundreds of horseshoe bats.

‘They found three with closely matched receptor binding domains - the part of the coronavirus' spike protein used to bind to human ACE-2, the enzyme it targets to cause an infection. The finding, reported in a paper released on Friday (Sept 17) that is under consideration for publication by Nature journal, shows that viruses closely related to Sars-CoV-2 exist in nature, including in several Rhinolophus, or horseshoe bat, species. The research supports the hypothesis that the pandemic began from a spillover of a bat-borne virus.’

Read here (Straits Times, Sept 18, 2021)

The origins of SARS-CoV-2: A critical review

Since the first reports of a novel severe acute respiratory syndrome (SARS)-like coronavirus in December 2019 in Wuhan, China, there has been intense interest in understanding how severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) emerged in the human population. Recent debate has coalesced around two competing ideas: a “laboratory escape” scenario and zoonotic emergence. Here, we critically review the current scientific evidence that may help clarify the origin of SARS-CoV-2.

We contend that although the animal reservoir for SARS-CoV-2 has not been identified and the key species may not have been tested, in contrast to other scenarios there is substantial body of scientific evidence supporting a zoonotic origin. Although the possibility of a laboratory accident cannot be entirely dismissed, and may be near impossible to falsify, this conduit for emergence is highly unlikely relative to the numerous and repeated human-animal contacts that occur routinely in the wildlife trade. Failure to comprehensively investigate the zoonotic origin through collaborative and carefully coordinated studies would leave the world vulnerable to future pandemics arising from the same human activities that have repeatedly put us on a collision course with novel viruses.

Read here (Cell, Aug 18, 2021). Download PDF here

Investigate the origins of Covid-19: ‘Take hypotheses about both natural and laboratory spillovers seriously’

‘As scientists with relevant expertise, we agree with the WHO director-general, the United States and 13 other countries, and the European Union that greater clarity about the origins of this pandemic is necessary and feasible to achieve. We must take hypotheses about both natural and laboratory spillovers seriously until we have sufficient data. A proper investigation should be transparent, objective, data-driven, inclusive of broad expertise, subject to independent oversight, and responsibly managed to minimize the impact of conflicts of interest. Public health agencies and research laboratories alike need to open their records to the public. Investigators should document the veracity and provenance of data from which analyses are conducted and conclusions drawn, so that analyses are reproducible by independent experts.’

Read here (Science, May 14, 2021)

China’s exotic farms may be a missing link behind the pandemic’s leap to people

‘Given that more than a year passed between late 2019, when the disease was linked to the market, and December 2020, when China says it shut down all its food-supplying wildlife farms, acquiring such evidence may prove impossible. Still, filling in gaps about how the virus may have leaped to humans is essential for understanding the COVID-19 pandemic and combating future zoonotic diseases.

‘Yunnan, the southern Chinese province where many of the now-shuttered wildlife farms are located, is also where virologists found a bat virus almost identical to the coronavirus circulating in humans. Some wildlife farms sold animals that can be infected with other coronaviruses, including civets, so scientists suspect that these species may also be susceptible to SARS-CoV-2, the virus that causes COVID-19. “Potentially, some of these animals were infected at those farms and then brought the virus into the market,” Peter Ben Embarek, the Danish food safety scientist heading WHO’s delegation, told Science in February, after he and the WHO team returned from China, adding that more testing was needed.’

Read here (National Geographic, Mar 25, 2021)

The secret weapon [abolishing factory farming] against pandemics that nobody wants to talk about | Alex O'Connor

‘Alex O’Connor is a prominent podcaster, YouTuber and student at the University of Oxford. In his TEDx talk, Alex puts forward the case against factory farming, not only based on ethical concerns, but also by exploring how factory farms can become breeding grounds for Zoonotic viruses.’

View here (TedTalk, Youtube, Mar 5, 2021)

The search for animals harbouring coronavirus — and why it matters

‘Ever since the coronavirus started spreading around the world, scientists have worried that it could leap from people into wild animals. If so, it might lurk in various species, possibly mutate and then resurge in humans even after the pandemic has subsided.

‘That would bring the tale of SARS-CoV-2 full circle, because wild animals probably brought it to humans in the first place. Strong evidence suggests that the virus originated in horseshoe bats (Rhinolophus spp.), possibly hitching a ride on other animals before infecting people1. In the current stage of the pandemic, with hundreds of thousands of confirmed COVID-19 infections every day, people are still driving transmission of SARS-CoV-2. But years from now, when community spread has been suppressed, a reservoir of SARS-CoV-2 in free-roaming animals could become a recalcitrant source of new flare-ups.’

Read here (Nature, Mar 2, 2021)

Where did Covid come from? Five mysteries that remain

‘In the wake of the World Health Organization’s investigation, there are still key questions about when, where and how the pandemic began.

1. Was the virus circulating in Wuhan before the first known cases?
2. Was the virus spreading in people outside China before December 2019?
3. What was the role of the Huanan market?
4. Did frozen wild-animal meat have a role in the early spread of the virus?
5. Was the virus circulating in animals in China before the pandemic?

Read here (Nature, Feb 26, 2021)

WHO team says theory Covid began in Wuhan lab ‘extremely unlikely’

‘The World Health Organization team that visited Wuhan to investigate the origins of the coronavirus pandemic has all but dismissed a theory that the virus leaked from a laboratory, while giving some credence to China’s focus on the possibility of transmission via frozen food.

‘They said the team’s work did not dramatically change the picture they had before they began, but had added important details to the story. The team found no evidence of widespread circulation of the virus in Wuhan prior to December 2019, and said it was still unclear how it got into the Huanan seafood market, where the virus was initially detected. But, they added, “all the work that has been done on the virus and trying to identify its origin continue to point toward a natural reservoir”.’

Read here (The Guardian, Feb 9, 2021)

After coronavirus: Our relationship with meat and the next pandemic

‘All pandemics in recorded human history have come via the animal kingdom. With mutations abounding and our interaction with wildlife widening, when are we finally going to address the sick animal in the room?...

‘To be precise, three out of four of those "new diseases" come from animals, and the frequency with which they have emerged has been accelerating for over 40 years... [Delia] Randolph was the lead author of a joint International Livestock Research Institute and UNEP report published in July looking into the reasons for this acceleration. Research from dozens of scientists spanning the globe came to one conclusion: human behaviour, i.e., the way we interact with and consume animals, is the main driver increasing the prevalence of zoonotic disease. 

‘The report lists seven "human-mediated factors" behind the emergence, with numbers one through three as follows: 1) increasing human demand for animal protein, 2) unsustainable agricultural intensification, 3) increased use and exploitation of wildlife.’

Read here (DW, Nov 20, 2020)

‘Mutant coronavirus’ seen before on mink farms, say scientists

‘The coronavirus mutation causing concern in Denmark has arisen before in mink, scientists have revealed. The mutated virus has been detected retrospectively in mink at a farm in the Netherlands, but it did not spread to humans, said a leading Dutch expert...

‘The genetic data from Denmark was released on an international database a few days ago, with some scientists questioning why it had not been released sooner. "I think that it is most disappointing that the data have only just reached the light of day," said Prof James Wood, head of the department of veterinary medicine at the University of Cambridge, UK...

‘Six countries have reported coronavirus outbreaks at mink farms: the Netherlands, Denmark, Spain, Sweden, Italy and the US.’

Read here (BBC, Nov 9, 2020)

Denmark to cull millions of minks over mutated coronavirus

‘Denmark, the world's biggest producer of mink fur, said Wednesday it would cull all of the country's minks after a mutated version of the new coronavirus was detected at its mink farms and had spread to people. The mutation "could pose a risk that future (coronavirus) vaccines won't work the way they should," Prime Minister Mette Frederiksen told a press conference, adding: "It is necessary to cull all the minks."

“The mutated virus could thereby have serious negative consequences for the whole world’s response to the ongoing pandemic,” she said. Danish police estimated that between 15 and 17 million minks would need to be put down. Twelve people are currently registered as infected with a mutated form of the coronavirus in Denmark, according to news wire Ritzau. The mutated virus is reported to respond weakly to antibodies.’

Read here (The Local, Denmark, Nov 4, 2020)