A surgical mask

Surgical and cotton masks don't do enough to shield droplets of SARS-CoV-2 (the virus that causes COVID-19) from escaping into the air after a cough, according to one university's study.

The discovery comes from researchers at Ulsan College of Medicine in Seoul, South Korea, whose findings were published in Annals of Internal Medicine, reports Infection Control Today.

In their study, the university researchers had four patients cough several times into a petri dish while wearing no mask. They then had the patients cough the same amount of times into a surgical mask, a cotton mask, and again without a masks. After analyzing the study, researchers found  that SARS-CoV-2 droplets were able to escape the mask of patients and make their way into the air.

Wearing a mask provided to reduce the amount of viral loads put into the air when compared to using no mask. However, the numbers weren't too encouraging. The researchers found 2.56 log copies per milliliter after coughs not covered by masks and 2.42 log copies per milliliter after coughs covered by surgical masks. Coughs covered by cotton masks yielded 1.85 log copies per milliliter. 

More SARS-CoV-2 particles were found on the outside of the masks than the inside.

Researchers says the study (which did not examine the effectiveness of N95 masks) further prove it's important to wash hands after touching the surface of masks.