New Study: Surgical Masks Stop Transmission Of COVID-19 From Symptomatic People

A recent study published by the journal Nature Medicine on April 3 said that surgical masks are effective barriers in preventing people from discharging infectious particles, at least quantity-wise. 

The research was conducted by the University of Maryland, College Park, and the University of Hong Kong on previous coronaviruses and not SARS-CoV-2. Be that as it may, the findings are relevant to the current pandemic. In fact, similarly, the World Health Organisation (WHO) updated its recommendations to say that asymptomatic people need not cover their face at all with a surgical mask. 

So, what did this particular study have to contribute to this current debate going back and forth on advice related to masks? Firstly, aerosol particles can be spread without sneezing or coughing. Just by the simple act of breathing, tiny droplets are emitted and cannot be stopped from spreading by surgical masks alone. It is the quantity of flu viruses shed by coughing and sneezing that is reduced when wearing a mask for protection, thereby controlling transmission to an extent.  

How Was The Study Conducted?

Researchers divided a team of 246 participants into two groups, all of whom suffered from a respiratory condition, either from influenza viruses, rhinoviruses, or old coronaviruses. One group was provided surgical masks, while the other group was not. 

A unique machine called Gesundheit II was designed to pick up exhaled particles to assess to what extent the masks captured these droplets. The device had helped confirm a previous study analyzing if the flu viruses could emit infectious particles without coughing or sneezing. Both studies said that masks cannot prevent droplets spread by regular breathing. 

It was found that when infected people wore the mask, the virus spread much less despite coughing and sneezing.“In 111 people infected by either coronavirus, influenza virus, or rhinovirus, masks reduced detectable virus in respiratory droplets and aerosols for seasonal coronaviruses, and in respiratory droplets for influenza virus. In contrast masks did not reduce the emission of rhinoviruses,” lead author Nancy H. L. Leung, Ph.D said. 

“Personal protective equipment like N95 masks are not our first line of defense. They are our last, desperate thing that we do,” senior co-author Professor Donald K. Milton said. Ventilation in public places and placing UVC lighting next to ceiling fans could kill infectious particles by attracting them towards the fan, Milton suggested.  

Are Cloth Masks Helpful?

While surgical masks may help symptomatic people, the Centers for Disease Control and Prevention (CDC) recommends everyone to wear face masks made from cloth when going out for essential shopping needs. But this technique may not be as helpful according to Prof. William Keevil, who teaches environmental healthcare at the University of Southampton. 

“Cloth masks and poor quality surgical face masks will not filter fine respiratory droplets, and certainly not aerosols, which some are now claiming to be an infection risk. The major question that needs to be addressed is: what about protecting the eyes, a known route of entry?,” he told The Guardian.

covid-19 face mask Federal and state health officials said it is important to regularly clean cloth homemade or cloth face masks with hot water and regular detergent to avoid the novel coronavirus that could stay on surfaces. Pixabay