Originally posted November 20, 2020.
At last, there is properly rigorous scientific research we can rely on in the age of Coronavirus. Evidence shows that wearing masks in communities does not significantly reduce the rates of infection.
On Wednesday, the Denmask-19 Trial, a long-delayed trial from Denmark, was finally published. The study from last spring involved 3,000 participants. At the time, the population at large was not being told to wear masks, but other public health measures were in place, reports the Spectator.US.
Unlike other studies looking at masks, the Denmask study was a randomized controlled trial — making it the highest quality scientific evidence.
Around half of those in the trial received 50 disposable surgical facemasks, which they were told to change after eight hours of use. After one month, the trial participants were tested using both PCR, antibody and lateral flow tests and compared with the trial participants who did not wear a mask.
In the end, there was no statistically significant difference between those who wore masks and those who did not when it came to being infected by COVID-19. Of those wearing masks, 1.8 percent caught COVID, compared to 2.1 percent of the control group. As a result, it seems that any effect masks have on preventing the spread of the disease in the community is small.
No Evidence Masks Prevent Spread of Airborne Diseases
When it comes to masks, it appears there is still little good evidence they prevent the spread of airborne diseases. The results of the Danmask-19 trial mirror other reviews into influenza-like illnesses. Nine other trials looking at the efficacy of masks (two looking at healthcare workers and seven at community transmission) have found that masks make little or no difference to whether you get influenza or not.
But overall, there is a troubling lack of robust evidence on facemasks and COVID-19. There have only been three community trials during the current pandemic comparing the use of masks with various alternatives — one in Guinea-Bissau, one in India and this latest trial in Denmark.
The low number of studies into the effect different interventions have on the spread of COVID-19 — a subject of global importance — suggests there is a total lack of interest from governments in pursuing evidence-based medicine. And this starkly contrasts with the huge sums they have spent on ‘boutique relations’ consultants advising the government.
Large, randomized trials like this most recent Danish study are important if we are to understand the impact of measures like facemasks, continues the Spectator.
Many people have argued that it is too difficult to wait for randomized trials — but Danmask-19 has shown that these studies are more than feasible.