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Inside the risky engineering of the bat virus linking America to Wuhan

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For Baric, this research began in the late 1990s. Coronaviruses were then considered low-risk, but Baric’s studies on genetics that allow viruses to enter human cells convinced him that some could. be only a few mutations by jumping the species barrier.

This intuition was confirmed in 2002 – ’03, when SARS broke out in southern China, infecting 8,000 people. As bad as it is, says Baric, we dodged a bullet with SARS. The disease did not spread from one person to another until about a day after severe symptoms began to appear, making it easier to correct it through quarantine and contact tracing. Only 774 people died in that outbreak, but if it had been transmitted as easily as SARS-CoV-2, “we would have had a pandemic with a mortality rate of 10%,” Baric says. “That’s how humanity is close.”

For temptation that was to cancel SARS as a unique event, in 2012 MERS developed and began to infect people in the Middle East. “For me personally, it’s been a wake-up call that animal reservoirs need to have many, many more strains that are ready for movement between species,” says Baric.

Later, examples of such dangers were already discovered by Shi’s team, which had spent years sampling bats in southern China to find the origins of SARS. The project was part of a global viral surveillance effort led by the nonprofit EcoHealth Alliance of the United States. The nonprofit — which has an annual income of more than $ 16 million, more than 90% of government grants — has its office in New York but partners with local research groups in other countries to do the fieldwork and of laboratories. The WIV was his crown jewel, and Peter Daszak, president of EcoHealth Alliance, co-authored with Shi on most of his keynote papers.

By taking thousands of samples from guano, fecal swabs, and bat tissues, and searching for these samples for genetic sequences similar to SARS, Shi’s team began discovering several tight viruses. In a cave in Yunnan province in 2011 or 2012, they discovered the two closest ones, called WIV1 and SHC014.

Shi was able to grow WIV1 in his lab from a fecal sample and show that it could directly infect human cells, showing that SARS-like viruses ready to jump directly from bats to humans were already hiding in the natural world. This showed, Daszak and Shi argued, that bat coronaviruses were a “substantial global threat.” Scientists, they said, needed to find them, and study them, before they could find them.

Many of the other viruses could not be cultured, but the Baric system provided a way to quickly test their tips by ingesting them into similar viruses. When the chimera he made with SHC014 was able to infect human cells in a dish, Daszak told the press that these revelations should “move this virus from a pathogenic emerging candidate into a clear and present danger.”

For others, it was the perfect example of the unnecessary dangers of the science of function gain. “The only impact of this work is the creation, in a laboratory, of a new unnatural risk,” Rutgers microbiologist Richard Ebright, a longtime critic of such research, told Nature.

For Baric, the situation was more nuanced. Although its creation might have been more dangerous than the original mouse virus adapted to the mouse it had used as a backbone, it was still timid compared to SARS – certainly not the supervirus Senator Paul suggested later.

In the end, the NIH clampdown never had teeth. It included a clause granting exceptions “if the head of the funding agency determines that research is urgently needed to protect public health or national security.” Not only were Baric’s studies allowed to move forward, but so were all studies that demanded exemptions. Funding restrictions were lifted in 2017 and replaced by a more lenient system.

Tyvek suit and respirators

If the NIH was looking for a scientist to make regulators comfortable with the pursuit of function gain, Baric was the obvious choice. For years and years he had insisted on more security measures, and it took a lot of pain to highlight them in his 2015 paper, as if shaping the road forward.

U CDC recognizes four levels of biosafety and recommends which pathogens should be studied at which level. Level 2 biosafety is for non-hazardous organisms and requires virtually no precautions: wear a lab coat and gloves as needed. BSL-2 is for moderately dangerous pathogens that are already endemic in the area, and relatively mild interventions are indicated: close the door, bring eye protection, throw scrap materials into an autoclave. BSL-3 is where business becomes serious. It is for pathogens that can cause serious diseases through respiratory transmission, such as influenza and SARS, and associated protocols include more barriers to escape. The laboratories are walled by two sets of self-closing doors, closed; the air is filtered; staff use full PPE and N95 masks and are under medical supervision. BSL-4 is for the worst of bad guys, like Ebola and Marburg: full moon clothing and dedicated air systems are added to the arsenal.

“There are no applicable rules of what should and should not be done. It affects individual countries, institutions and scientists.”

Filippa Lentzos, King’s College London

In Baric’s lab, chimeras were studied in BSL-3, enhanced with additional steps such as Tyvek clothing, double gloves and air-fed respirators for all workers. Local first responder teams have participated in regular exercises to increase their familiarity with the lab. All workers were monitored for infections, and local hospitals had procedures in place to treat incoming scientists. It was probably one of the safest BSL-3 installations in the world. That wasn’t even enough to prevent it a handful of mistakes over the years: some scientists have even been bitten by mice carrying the virus. But no infection resulted.

New pathogens

In 2014, the NIH awarded a five-year, $ 3.75 million grant to the EcoHealth Alliance to study the risk that more coronavirus-transmitted coronaviruses would emerge in China, using the same type of techniques that Baric had opened up. Part of this work had to be subcontracted to the Wuhan Institute of Virology.


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