- Droplets expel from nose, mouth when a person talks, sings, sneeze: Experts
- Smaller droplets are more dangerous than the larger droplets: Experts
- Facemasks are recommended as first defense against COVID-19 by WHO
Singapore: The COVID-19 pandemic could be stopped if at least 70 per cent of the public wore face masks consistently, according to a review of studies which suggests that the type of material used and the duration of mask use play key roles in their effectiveness. The research, published in the journal Physics of Fluids, assessed studies on face masks and reviewed epidemiological reports on whether they reduce the number of people an infected person spreads the pathogen to — the reproduction number of the virus.
The highly efficacious facemask, such as surgical masks with an estimated efficacy of around 70 per cent, could lead to the eradication of the pandemic if at least 70 per cent of the residents use such masks in public consistently. Even less efficient cloth masks could also slow the spread if worn consistently, the scientists, including Sanjay Kumar from the National University of Singapore, wrote in the study.
According to the scientists, one key aspect of face mask function involves the size of fluid droplets expelled from the nose and mouth when a person talks, sings, sneezes, coughs, or even simply breathes. They said larger droplets, with sizes around 5-10 microns, are the most common, adding that smaller droplets below 5 microns are possibly more dangerous. In comparison, the scientists said the human hair is about 70 microns in diameter.
Among the many types of facemasks in use, such as cloth masks, surgical masks, and N95 masks, they said only the latter can filter out aerosol-sized droplets. The performance of face masks worn for many hours, such as by health care or other essential workers, impact how effective overall mask-wearing can be, the researchers added.
They found that face masks made of hybrid polymer materials could filter particles at high efficiency while simultaneously cooling the face since the fibres used in these allow heat to escape from beneath the mask.
There could be some relation between breathing resistance and the flow resistance of the face mask which will need to be studied for a face mask-wearing interval. Also, the environmental condition in the compartmental space within the face mask will need to be more accurately quantified using miniaturised sensors and the development of human replicas for such studies, said Heow Pueh Lee, another co-author of the study.
Based on the analysis, the researchers underscored the importance of consistent use of efficient facemasks, such as surgical masks.
(Except for the headline, this story has not been edited by NDTV staff and is published from a syndicated feed.)
NDTV – Dettol Banega Swasth India campaign is an extension of the five-year-old Banega Swachh India initiative helmed by Campaign Ambassador Amitabh Bachchan. It aims to spread awareness about critical health issues facing the country. In wake of the current COVID-19 pandemic, the need for WASH (Water, Sanitation and Hygiene) is reaffirmed as handwashing is one of the ways to prevent Coronavirus infection and other diseases. The campaign highlights the importance of nutrition and healthcare for women and children to prevent maternal and child mortality, fight malnutrition, stunting, wasting, anaemia and disease prevention through vaccines. Importance of programmes like Public Distribution System (PDS), Mid-day Meal Scheme, POSHAN Abhiyan and the role of Aganwadis and ASHA workers are also covered. Only a Swachh or clean India where toilets are used and open defecation free (ODF) status achieved as part of the Swachh Bharat Abhiyan launched by Prime Minister Narendra Modi in 2014, can eradicate diseases like diahorrea and become a Swasth or healthy India. The campaign will continue to cover issues like air pollution, waste management, plastic ban, manual scavenging and sanitation workers and menstrual hygiene.[corona_data_new]