Initially, face masks were mostly worn by medical and laboratory personnel to reduce the risk of coming into contact with pathogens present in droplets and sprays. Since the beginning of the pandemic, in most countries, individuals are required to use face masks as a protection against viral infection and, ultimately, COVID-19. Questions have been raised as to the effectiveness of this measure and the graveness of the consequences associated with not sticking to it.
The facts and figures
Since the invention of face masks, there have been significant statistics and data collection on their role as a preventive measure against viral infections. These data provide interesting insights which could serve as the basis for a safe inference on the potency of face masks.
In 2004, a survey was conducted in Beijing on the efficacy of face masks in preventing the spread of SARS (Severe Acute Respiratory Syndrome). The study showed that the use of face masks was strongly protective against the deadly virus, providing a risk reduction of up to 70% for those who always used them.
In 2008, another Australian study determined how effective face masks were in controlling the spread of influenza. The survey revealed that face masks gave users 80% protection against the virus and other “clinical influenza-like illnesses”.
A more recent 2020 study examined the usefulness of face masks in preventing the spread of COVID-19. Researchers reviewed past surveys conducted between 2000 and 2020 on the effectiveness of face masks in preventing other viral respiratory tract infections. The analysis concluded that face masks indeed worked to prevent the spread of viral respiratory tract infections, including those sharing many behavioural characteristics with the novel coronavirus.
Experts from the University of Edinburgh Usher Institute found that face masks do reduce transmission of viral infection through droplets if infected individuals use them. Using a mask when breathing, sneezing, or coughing can reduce aerosol dispersal and the transmission range of droplets.
Surveys on the effectiveness of face masks have been conducted at various times when different viral respiratory tract infections have arisen. Varying circumstances may have had effects on the results, but the finding that face masks reduce the risk of viral respiratory tract infections stood true for all the aforementioned surveys.
During some of the times the studies were conducted, there was no enforcement by law to use face masks, and individuals chose whether or not to wear them based on their perception of associated risks. One of the surveys recognized this factor and highlighted that the effectiveness of face masks would be higher in situations where everyone was compliant with its usage.
The potency of a face mask
Face masks go a long way in curbing the spread of viral infections and mitigate the risk factors of viral infections. They are made using thin non-woven fabrics that are porous enough to permit breathing but blocking droplets as large as the size of most viruses. Masks serve as a two-way protection to a certain degree, filtering particles from the external environment and also limiting the number of droplets an individual releases into the atmosphere.
When individuals use face masks, they protect themselves from airborne contagions and droplets that could readily transmit from infected persons nearby. On the flip side, when an infected person uses a face mask, a significant proportion of droplets from the nose and mouth remain trapped in the mask. This could reduce the rate at which infected persons will infect others, especially during the asymptomatic periods of infection. Even when there are no infected persons around, it is still safer to wear a face mask as droplets containing harmful viruses can propagate within the lower atmosphere for a distance as far as 5 meters from the source.
According to the World Health Organization, the use of face masks is only one of the many strategic measures for reducing the spread of viral respiratory tract infections such as COVID-19 and influenza. When face masks are used alongside other protective measures such as proper hygiene, social distancing, vaccines, and clinical isolation, they have the most beneficial effects.
Using a face mask significantly reduces the risk of viral infection through contact with infected respiratory particles. The most potent of all protective measures against respiratory tract infections would be social distancing. However, a face mask could serve as an additional protective measure where contact with other persons is inevitable. For instance, in social gatherings or when attending to patients as medical personnel, using a face mask is highly recommended as it significantly limits the number of infectious particles that can be exchanged.