Two items of recent pandemic news: Sanofi & GSK get some good news from a Phase II study of their reformulated vaccine candidate; and questions swirl anew around the origins of the pandemic virus. Plus news briefs and a frippery.

The question is not settled. The WHO’s investigation team sent to China early this year did not provide a conclusive answer. Four possibilities are on the table: (1) SARS-CoV-2 jumped from bats to an (unidentified) intermediate species and then into humans, or (2) jumped directly to humans, or (3) came to people via fresh or frozen food, or (4) escaped from a laboratory by accident. None can be proved. None can be ruled out.

We haven’t paid any attention here to the origin question. Part of the reason is that over 2020 the issue was highly politicized — the lab escape theory (4) was pushed by an administration that had good reason to want to deflect blame from its (literally disastrous) performance in the pandemic. And of course many in the scientific community reflexively discounted whatever came out of the mouth of the previous, relentlessly anti-science, president.

But just because Trump said it, that does not make it automatically wrong.

The WHO’s report gives qualitative weights to the origin options as follows:

1. Spillover via an intermediate species: likely to very likely
2. Direct spillover: possible to likely
3. Transmission via food or cold-chain: possible
4. Release from a laboratory: extremely unlikely

The report’s release in late February resulted in immediate calls for a more complete and transparent in­ves­ti­ga­tion, including by the WHO’s director-general. Dr. Tedros Adhanom Ghebreyesus said he does not believe the team’s assessment of the lab leak possibility was extensive enough.

Making the case for a lab leak — The proximate factor stirring up interest in the Covid origin question at this time is a long argument (10,000+ words) for taking the lab accident hypothesis seriously. It was published on May 5 in the Bulletin of the Atomic Scientists; the author is former Nature and NYTimes science journalist Nicholas Wade.

Wade’s report was favorably recommended by Tucker Carlson (“lays out a nearly insurmountably large amount of evidence that this virus originated at the Wuhan Institute of Virology in central China”) and seems to be the source of a beef between Rand Paul and Dr. Anthony Fauci, on the occasion of Fauci’s appearance at a Senate hearing last week. Sen. Paul demanded that Fauci comment on “gain of function” (GoF) research performed at the Chinese institute under a subcontract to work funded by the National Institutes of Health’s NAIAD, which Fauci leads. Fauci retorted that the NIH did not now and never had funded GoF research in Wuhan.

Gain of function — The Washington Post’s fact checker, Glenn Kessler, in examining the Paul-Fauci scuffle, lays out the range of things people mean when they use that term in the context of virology.

Kessler’s column in the end mostly sides with Fauci and awards Paul two Pinnochios for his insinuation that NIH – NIAID paid for GoF research at the Wuhan Institute of Virology. Kessler concluded “There is some smoke here, but we do not yet perceive the fire claimed by Paul.”

The default assumption — For the ultimate source of SARS-CoV-2, natural emergence (or zoonotic spillover) has been the default assumption, except in right-wing circles, since a group of researchers published an attack on the lab escape hypothesis “conspiracy theory” in The Lancet on February 19, 2020.

But as it turns out, that attack letter had been surreptitiously orchestrated by a scientist (Peter Dashzk) involved with a US public-health nonprofit (the EcoHealth Alliance) that had won a contract from the National Institutes of Health’s NAIAD, and subcontracted part of the work to the Wuhan Institute for Virology from 2014 to 2019.

Wade’s report contends that the NIH contract was for GoF research on betacoronaviruses from bats. Kessler, of the WaPo, quotes a spokesman for the EcoHealth Alliance to the effect that the parts of the contract whose wording could be interpreted as GoF were never carried out: NIH money paid for some bat sample collection in China.

Here is some of the circumstantial evidence that Wade corrals to make the case that a lab leak origin for SARS-CoV-2 cannout be dismissed:

— The Wuhan virology lab had moved in December 2019, as the WHO’s report notes, and such a move can be dis­rup­tive to procedures such as safety routines. While the lab was rated for BSL-4 containment work, some of its research was carried out in BSL-2 conditions — lab coats, goggles, gloves. Work on bat coronaviruses other than SARS and MERS was carried out under BSL-2. A BSL-2 lab does not involve bunny suits or sealed, positive pressure rooms with strict protocols for donning and doffing protective gear.

— The hospitals admitting the first cases of Covid-19 in the city of Wuhan are clustered along that city’s subway line No. 2, which connects the virology institute with the international airport.

Going mainstream — After a spring in which talk about, and journalistic coverage of, the lab leak option moved from Fox News hosts and right-wing talk radio into mainstream outlets, a different group of experts, whose members do not overlap with the Lancet assemblage, has published a letter in Science titled “Investigate the origins of COVID-19.” They call for an investigation that is “transparent, objective, data-driven, inclusive of broad expertise, subject to independent oversight, and responsibly managed to minimize the impact of conflicts of interest.”

The Biden administration has not ruled out a lab leak. As David Frum reports in The Atlantic:

After the hiccup last December when their first vaccine candidate proved not to develop enough of an immune response in older adults, the companies announced preliminary Phase II results for a revised formula.

The companies put out a press release, promising to follow up with publication in a refereed scientific journal.

In 722 volunteers aged 18 to 95, the Sanofi vaccine candidate boosted by a GSK adjuvant induced rates of neutralizing antibodies at levels similar to those seen in people who have recovered from Covid-19. These results applied across all adult age groups, though higher levels were observed in those 18 to 59 years old. No safety or tolerability concerns were noted.

Sanofi and GSK also mentioned that for those who had recovered from Covid-19, the vaccine candidate provided good seroconversion after a single dose. This bodes well for the drug’s use as a booster shot in the later phases of the pandemic.

A Phase III study enrolling 37,000 volunteers will get under way in the coming days in countries around the world, to include South Africa. Sanofi also plans to test other formulations tweaked to respond to variants such as B.1.351.

The companies plan to produce a billion doses annually, in addition to helping other vaccine makers with manufacturing. Sanofi has signed deals to help Johnson & Johnson, Moderna, and Pfizer; GSK will be manufacturing for CureVac and Novavax.

• Com-COV results — We wrote last week about the Com-COV study investigating mixing doses of different vaccines to see how the immune response is affected. Preliminary results are in after 28 days of observation following the second shot (CIDRAP summary, paper in The Lancet), but they are mostly about tolerability and reactogenicity. Participants who received different shots (in either order) had more side effects than those who got two shots of the same vaccine. More results will come out later when another study cohort receives their second shot after 84 days.
• Will you stay masked? — Slate has an interview with an ER doc who discloses how her personal behavior will or will not change following the CDC’s change of heart on masking. I especially like her quick answers to the interviewer’s “lightning round” of questions. Here is the podcast for those who prefer that format.

Here is the reward for your patience in getting this far: the frippery today is a test of your ability to defeat dark patterns of user in­ter­action. In this game you get 29 tries (with a timer running) to outwit Evil Corp’s dasterdly and devious at­tempts to obtain your private data.

Let us know how you scored in the comments below. On my first try I was fooled by 5 of 29 puzzles and scored at the 66th percentile among site visitors.