AS NEW information regarding Covid-19 come in, health protocols are revised. An example of this is the wearing of face mask. At the start of the Enhanced Community Quarantine (ECQ), it was not compulsory. In fact in late March, the Inter-Agency Task Force (IATF) clarified that it did not require face masks when entering supermarkets, in reaction to grocery stores requiring customers to wear them.

At the start of April however, there was a shift in policy. Malacañang ordered all those living in areas under ECQ to wear face masks or other forms of protective equipment when they go out to buy essential items. Here in Pampanga, the Sangguniang Panlalawigan passed an ordinance on the third week of April making the wearing of face mask mandatory.

Even the World Health Organization (WHO) recommended the wearing of face masks only recently. On April 6, it released a guidance saying that healthy people don't need to wear face masks to prevent coronavirus spread. It added that face masks are reserved for medical workers.

However on June 5, WHO updated its guidance. The health body now advised that to prevent Covid-19 transmission effectively in areas of community transmission, governments should encourage the general public to wear masks in specific situations and settings as part of a comprehensive approach to suppress Sars-CoV-2 transmission. The new guidance had been prompted by studies over recent weeks.

At the University of Cambridge, a study suggests that population-wide use of facemasks keeps the coronavirus "reproduction number" under 1.0, and prevents further waves of the virus when combined with lockdowns. The research suggests that lockdowns alone will not stop the resurgence of Sars-CoV-2, and that homemade masks with limited effectiveness can dramatically reduce transmission rates if worn by enough people, regardless of whether they show symptoms. The findings are published in the 'Proceedings of the Royal Society A'.

The new coronavirus is transmitted through airborne droplets loaded with Sars-CoV-2 particles that get exhaled by infectious people, particularly when talking, coughing or sneezing. The researchers point out that even crude homemade masks primarily reduce disease spread by catching the wearer's own virus particles, breathed directly into fabric, whereas inhaled air is often sucked in around the exposed sides of the mask.

The reproduction or 'R' number -- the number of people an infected individual passes the virus onto -- needs to stay below 1.0 for the pandemic to slow. The study found that if people wear masks whenever they are in public it is twice as effective at reducing 'R' than if masks are only worn after symptoms appear.

In all modelling scenarios, routine face mask use by 50 percent or more of the population reduced Covid-19 spread to an R less than 1.0, flattening future disease waves and allowing less-stringent lockdowns. A 100 percent mask adoption combined with on/off lockdowns prevented any further disease resurgence for the 18 months required for a possible vaccine.