While announcing the first ever cases of COVID-19 community transmission in Kerala in two coastal areas of Thiruvananthapuram on July 17, Chief Minister Pinarayi Vijayan also drew attention to a scientific study in the United States which, he said, should convince more people to start using face coverings regularly.
“What the study proves is that if we take care to wear masks, we can prevent the transmission of the disease almost completely. If such a simple precautionary measure can protect us from a calamity, is it not prudent to go ahead with that precaution? We must also encourage others to take that precaution. It is important for everyone to wear masks,” he said.
All through the week, the Chief Minister has been talking about the grim situation in Kerala and telling people repeatedly that “prevention is better than cure”, “vigil has the value of life”, and “anyone can get the disease from anyone else”, the last two being the new slogans of the third phase of the so-far effective “Break the Chain” campaign.
But the vigil that had stood the State in good stead for nearly six months must have gone slack, as for nearly a week now, Kerala has been reporting over 700 new cases every day (as against 200 in the first week of June). The total number of cases had risen to 10,275 by July 16. (See also, “ Fear over the cities ”, Frontline , July 31, 2010).
The State has so far reported 84 COVID-19 infection clusters, and authorities say ten of them are “large clusters”. In the past few days, Thiruvananthapuram city, with 1,279 cases, accounted for nearly half of the total number of daily infections in the State. Three zones in the coastal areas of the city are now the focus of an intense multi-agency containment effort.
The Chief Minister said people had started ignoring warnings, referring pointedly to the opposition-sponsored agitations in all the districts, the crowd of parents before entrance examination centres on July 16, the rush of customers in markets and shops, and the throng of passengers in private buses, especially in the northern districts. On a single day, on July 17, following what has become a familiar pattern, 4,944 instances have been officially reported in the State of people not wearing masks in public places.
Vijayan said he was therefore drawing attention of the State to the scientific study reported in the “Morbidity and Mortality Weekly Report” (MMWR) of the Centres for Disease Control and Prevention (CDC) in the U.S., about the case of two COVID-19 positive hairstylists in Springfield, a city in the U.S. State of Missouri.
Though the two hairstylists had been infected with COVID-19 and had shown symptoms of the disease, they continued to go to work for several days. During that time, they had served 139 customers who had come to the salon. They had spent 15 minutes on an average with each client. There were also cases where the interaction lasted up to 45 minutes. But none of the 139 customers got the disease, even though they had interacted closely with the stylists.
The study found that this was because both the hairstylists and their clients had worn masks. “On the other hand, the entire family of one of the hairstylists became infected, possibly because she did not wear a mask once she reached home, transmitting the disease to her family members. But none of her co-workers, who wore masks, got the disease,” the Chief Minister said.
The report of the study titled, “Absence of Apparent Transmission of SARS-CoV-2 from Two Stylists After Exposure at a Hair Salon with a Universal Face Covering Policy—Springfield, Missouri, May 2020”, released on July 17, said that Springfield city law and the salon company’s policy both insisted on “the use of face coverings at indoor and outdoor public places where physical distancing was not possible” and “reduced seating within the building to 25 per cent of normal capacity”. These were likely to be important factors that prevented the spread of SARS-CoV-2 between the stylists and their clients.
The authors said that SARS-CoV-2 spread mainly between persons in close proximity to one another (that is, within six feet) and the more closely a person interacted with an infected person and the longer the interaction, the higher the risk of transmission.
“Although the virus is spread largely through respiratory droplets when an ill person coughs or sneezes, data suggest that viral shedding starts during the two-to-three day period before symptom onset, when viral loads are at their highest. Although the rate of transmission of SARS-CoV-2 from pre-symptomatic patients (those who have not yet developed symptoms) and asymptomatic persons (those who do not develop symptoms) is unclear, these persons likely contribute to the spread of SARS-CoV-2. With the potential for pre-symptomatic and asymptomatic transmission, widespread adoption of policies requiring face coverings in public settings should be considered to reduce the impact and magnitude of additional waves of COVID-19,” the report said.
Previous studies have shown that both surgical masks and homemade cloth face coverings can reduce the aerosolisation of virus into the air and onto surfaces. The researchers found that both hairstylists had worn double-layered cloth face coverings or surgical masks while seeing clients. And, 47 per cent of the clients wore cloth face coverings, 46 per cent wore surgical masks, and about 5 per cent wore N-95 respirators. “The main protection individuals gain from masking occurs when others in their communities also wear face coverings,” the report said.
The MMWR issue also included another case study report by the Journal of the American Medical Association (JAMA), which showed that “adherence to universal masking policies reduced SARS-CoV-2 transmission within a Boston hospital system”.
A press release issued by the CDC on July 14 announcing the results also quoted CDC director Dr Robert R. Redfield as saying: “We are not defenceless against COVID-19. Cloth face coverings are one of the most powerful weapons we have to slow and stop the spread of the virus–particularly when used universally within a community setting.”