- A study that highlights masks as the most effective tool against Covid-19 has come under scrutiny by scientists in a published letter
- The study also claims that airborne transmission is the most prolific route of the coronavirus, which the letter disputes
- The paper was spearheaded by Marion Molina – a chemist who won a Nobel Prize for his contributions to identifying the link between the hole in the ozone layer and chlorofluorocarbon gases used in aerosol cans
There’s a feud brewing in academia.
As scientists rush to learn more about the coronavirus sweeping across the world, the checks and balances in peer-reviewing have become less stringent in an effort to get as much information about the virus to governments and health agencies as quickly as possible.
But one particular study has provoked the ire of more than 40 scientists. Published in the Proceedings of the National Academy of Sciences (PNAS) on 11 June, a paper claims that the coronavirus’s main route of infection is airborne, and that masks are the single most important preventative measure against its spread.
Analysing data and policies from the pandemic’s epicentres – Wuhan, New York City and Italy – it holds that physical distancing isn’t effective by itself, adding that the virus spreads through long-range airborne transmission.
Headed by Nobel laureate
It compared statistics from New York City that mandated the wearing of masks with outbreaks in the rest of the US to make some of its claims.
“With physical distancing, quarantine, and isolation in place worldwide and in the United States since the beginning of April, airborne transmission represents the only viable route for spreading the disease, when mandated face covering is not implemented,” says the study.
The paper also criticised the World Health Organisation (WHO), governments and the CDC for focusing its messaging too much on contact transmission instead of airborne transmission, despite WHO including the wearing of face cloths in its official guidelines policy.
The paper was helmed by Nobel laureate Mario Molina, who received recognition for his contributions to identifying chlorofluorocarbon gases used in aerosol cans and refrigeration as damaging the earth's ozone layer.
He’s currently working at the University of California.
Calls for retraction
But the paper is being heavily scrutinised following an open letter to PNAS, urging them to retract the paper due to various false statements and questionable methodology. It was published on the website of the Meta-Research Innovation Centre at Stanford.
The letter – signed by leading scientists and experts in epidemiology from Stanford University, Johns Hopkins University and the University of Colorado – says that it’s erroneous to claim that policies were exactly the same in New York City and the rest of the US, except for the wearing of face masks.
It also adds that you can’t compare the epicentres with each other without accounting for regional differences in demographics, policies and contact behaviours.
Besides the "false" statements, they also flagged errors in the methodology, like ignoring the lag between changes in disease transmission and reported cases, as well as making it seem like policy implementation and actual population behaviour correlated accurately.
Adverse effect on policies
“If similarly false statements about exposure were made widely in a cohort study or a randomised control trial, a rapid and complete retraction of the study would quickly follow,” reads the letter.
“Hence, it is our view that PNAS is obligated to issue retraction of this work on these grounds alone.”
They add that these claims could have an adverse effect on policies.
“Unfortunately, since its publication on June 11, this article has been distributed and shared widely in traditional and social media, where its claims are being interpreted as rigorous science.
“As societies debate the risks of re-opening and relaxing physical distancing measures, it is crucial that decisions rely on a solid evidence base.”
The problem with contributed submissions
Another demand the letter makes is for PNAS to reevaluate their submission process, specifically Contribution Track submissions, which is how Molina got the paper published.
According to PNAS’s editorial and journal policies, members of NAS like Molina can present up to two submissions a year where the author also gets to select two of the reviewers.
According to the normal method – which is via Direct Submissions – a paper is reviewed by an editorial board, three NAS member and five qualified reviewers. There is no guarantee that your paper will be published, and it can be rejected in any of the various rounds.
Thus, the current process moves more quickly and authors have far fewer hurdles to jump through.
Response to the letter
In response to the letter, Molina told Buzzfeed that he rejected the criticism, stating that epidemiologists weren’t looking at viral droplets in the air, and that, as a specialist in air pollution, he just applied his expertise to the coronavirus.
Buzzfeed noted however that non of the authors that had contributed to the paper, including the reviewers, were experts in infectious disease epidemiology.
This drama comes on the heels of another academic furore, when earlier this month, The Lancet retracted a large study on hydroxychloroquine. It claimed that malaria drug, as well as chloroquine, was not an effective treatment for Covid-19 and could have serious side-effects.
Its publication halted clinical trials on the drug around the world, and then suddenly was retracted due to uncertainty about the data. Already then questions were raised about the review process of fast-tracked Covid-19 studies during the pandemic.
There is no word yet from PNAS on what they will do.
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