Safe drinking water, clean cooking gas, clean air, safe roads, no smoking in public places save more lives per year than all the hospital-based care put together. Similarly, condoms for safe sex have protected many people from sexually transmitted diseases including HIV. Helmets and seat belts saved many lives from road accidents.

According to the estimates by CDC, WHO, and Global Health partners, approximately 650,000 people die every year due to air-borne influenza viruses. According to the Global Burden of Disease study published in Lancet (2018), in 2016, lower respiratory tract infections caused ~2.4 million deaths worldwide (~0.65 million in children under 5, and ~1.1 million deaths in adults over 70 years of age). The majority of these infections are airborne or transmitted through droplets. There are millions more absent from work due to mild to moderate respiratory infections (cough and colds).

Urbanization has been growing rapidly across the world along with industrialization. Millions undertake daily travel in crowded public transport. Most modern offices are centrally air-conditioned becoming a potential path for the spread of air-borne microbes. Daily shopping has shifted to large malls where thousands of people gather every day. Large public gatherings (religious, political, sports, entertainment, etc.,) are a common feature. This increases the chances of contracting respiratory pathogens manifold compared to rural living.

Urbanization has also increased air pollution to dangerous levels in many cities and towns across the world. Air pollution is known to cause an increased incidence of heart attacks, higher incidence or worsening of asthma, and acute exacerbation of chronic lung diseases. Other effects include tiredness, burning of eyes, irritation of the nose, and throat. Air pollution is one of the leading risk factors for deaths, estimated to account for 5 million excess deaths globally every year.

Face masks emerged to protect people exposed to high air pollution levels. N95 and N99 face masks have evolved to filter toxic microparticles. The numbers denote filtering efficiency (For example, N95 has the capacity to filter up to 95% of the airborne particles measuring less than 5 microns). In addition to filtering particulate matter, these masks are also capable of filtering microbes. Surgical masks filter macroparticles (above 5-micron size) like bacteria and some of the large viruses like Coronaviruses.

Respiratory diseases are the third leading cause of death and disability globally. Respiratory infections and air pollution contribute to a significant proportion of these deaths and disabilities, smoking being the other major causative factor. Effective tobacco control, vaccinations in vulnerable people, and measures aimed at reducing air pollution have been proved to reduce the burden of respiratory diseases. In this context, the use of face masks in high-risk areas and by high-risk individuals may have a large impact on respiratory disease burden by reducing transmission of air-borne infections and offering protection from air pollution. Promotion of face mask use as a public health measure should come on to policy agenda of global health organizations and national ministries of health.

In summary, there is a compelling case for promoting face mask use as a public health policy measure with a large impact on population health along with improved productivity.

About the author- Dr. N. Krishna Reddy, MD DM(Card), Country Director, ACCESS Health International (India)