Face masks not 100% effective at preventing spread of COVID-19 - CDC

Face masks and coverings are not 100% effective at preventing the spread of the coronavirus, according to a September study from the US Centers for Disease Control and Prevention (CDC). The study, conducted in July, found that over 70% of the 154 'case-patients,' who had tested positive for COVID-19, were infected despite making efforts to abide by CDC guidelines, including the wearing of face masks. However, some have claimed that the basis of the study might be flawed in that only 11 people in the whole study never wore masks, meaning that because the group size is so uneven, a comparison of the proportion of people who tested positive for the virus who wore masks versus those who didn't is not sound. It is possible that some of the infections may have been caused by removing face coverings for food or drink. Another possibility is airflow, as “direction, ventilation and intensity of airflow might affect virus transmission, even if social distancing measures and mask use are implemented according to current guidance,” according to the CDC report. This is reflective of an incident at Tel Aviv's Sourasky Medical Center, where a doctor and two nurses may have been infected with the coronavirus by the aerosol coming from a ventilator being used on a patient. However, the CDC report further explained that it is impossible to evaluate exactly where someone contracted the virus. “Characterization of community exposures can be difficult to assess when widespread transmission is occurring, especially from asymptomatic persons within inherently interconnected communities,” the report stated. Infection with COVID-19 despite wearing protective measures has been recorded, with even medical professionals equipped with maximal personal protective equipment (PPE) occasionally contracting the virus. Despite this, face masks are still shown to be the most effective means of slowing the spread of the virus, and medical bodies worldwide recommend wearing them and maintaining social distancing measures. Moreover, cloth masks specifically are mainly intended to reduce the spread of coronavirus from infected to uninfected people. Editor's note: This article was amended on February 8 to improve accuracy.

Face masks not 100% effective at preventing spread of COVID-19 - CDC

It is impossible to evaluate exactly where someone contracted the virus.

New cancer shot dissolves whole tumors in patients

Broccoli is healthy – but here is what they didn't tell you

Face masks not 100% effective at preventing spread of COVID-19 - CDC

It is impossible to evaluate exactly where someone contracted the virus.

See more on