As the Covid-19 virus spread the world in February and March, some nations were quick to require citizens to wear masks wherever they went.  The science was uncertain at the time, with the World Health Organization not recommending their use.  Not only were there concerns regarding their efficacy in a non-clinical environment, but there were also concerns about the supply of masks to clinical environments if the public bought masks en masse, and also that wearing a mask might encourage a reduction in adherence to social distancing measures, which were believed to be more important.

After a prolonged period of time, new research from the University of Cambridge has been able to definitively answer this final concern.  Not only do the researchers find that there is no evidence that mask wearing leads to riskier behavior among wearers, but they suggest that the very concept of ‘risk compensation’ among policymakers may do most harm.

“The concept of risk compensation, rather than risk compensation itself, seems the greater threat to public health through delaying potentially effective interventions that can help prevent the spread of disease,” the researchers explain.

Covering up

While the science behind the benefits of face coverings in a regular context is still by no means certain, the researchers believe that the costs associated with wearing are so small that it makes sense to encourage it.

The team measured the evidence for risk compensation to see whether those early fears of the WHO were well founded.  Risk compensation suggests that people have a level of risk they’re comfortable with, and they subsequently adjust their behavior to ensure that level is maintained.

The researchers assessed dozens of reviews regarding both the efficacy of mask wearing on the transmission of respiratory virus infections and also on other behaviors linked to reducing the spread of such viruses, such as hand hygiene and social distancing.  None of these studies noted any reduction in these other measures as a result of mask wearing, and indeed, in two of the studies, hand hygiene actually improved among mask wearers.  In other studies, they found that people would often move away from mask wearers, which would increase physical distancing rather than reduce it.

“Many public health bodies are coming to the conclusion that wearing a face covering might help reduce the spread of SARS-CoV-2, and the limited evidence available suggests their use doesn’t have a negative effect on hand hygiene,” the researchers say.

It is, the researchers believe, time to lay the risk compensation theory to rest, and that by burying it, it will allow policymakers to prevent the continued threat it poses to public health.