Health officials have recently acknowledged that there is inadequate evidence to support the notion that medical-grade face masks, including N95, KN95, and FFP2 types, provide protection for vulnerable individuals against COVID-19, according to a report from The Telegraph.
The U.K. Health Security Agency (UKHSA) published a rapid review report investigating whether masks protect those at high risk from the disease, but was unable to find any scientific research with “usable data” to address the question.
The rapid review examined 4,371 studies but found none that explored the effectiveness of N95 and equivalent masks for those at a higher risk of severe illness when used within community settings.
“The review did not identify any studies for inclusion, and so could provide no evidence to answer the research question,” the authors said. “No studies matching the inclusion criteria were found, so no evidence could be presented.”
Professor Carl Heneghan from the University of Oxford expressed his concern, stating it is “a significant failing” that no high-quality trials have been conducted on mask effectiveness.
He also highlighted the importance of this issue for those at high risk, saying, “For those people at low risk, these questions don’t necessarily matter too much, but if you’re at high risk, you really want this question to be addressed. You want to know the answer.”
Heneghan further cautioned that the absence of robust clinical trials and data collection puts society at risk of repeating past mistakes in future pandemics.
“If there’s another pandemic around the corner, we still haven’t addressed any of these issues. We’ve not learned anything,” he said.
A recent Cochrane review published last month also concluded that there was insufficient evidence to make a determination on the effectiveness of masks, the Telegraph notes.
The review stated that it is impossible to say whether masks work or not due to the lack of quality data.
Professor Paul Hunter, from the Norwich School of Medicine, shared his thoughts: “Masks did reduce risk of transmission by about 20 per cent and in the early days of the pandemic that was really important. But they were never the cast-iron guarantee that some people seem to have been saying.”
Dr. Aodhán Breathnach, a Consultant Global Health Microbiologist at UKHSA, echoed this uncertainty, stating, “It is maybe surprising that there is no conclusive evidence one way or another [as to whether masks work], given that SARS-CoV-2 is perhaps the most studied virus ever, and masking was always a debated topic.”
“Nonetheless, the fact that the studies that do exist (including our own late addition) fail to show convincing evidence of benefit from masking suggests that, if there is a benefit, it is a rather modest one, i.e. masks may reduce the risk slightly but do not guarantee you won’t get infected.”
