About 20% of 4,500 people surveyed across all districts of the State were not protected by face masks, either because they did not wear a mask or wore it improperly, according to a study by the Global Institute of Public Health, Thiruvananthapuram.
The study found that 96% of people wore masks, but 16% wore them improperly, without covering the nose or mouth. Proper mask use was highest in Malappuram district (85.8%), which was also coincidentally classified as a “high zone” (district with a cumulative caseload of over 8,000 till August 28).
Thiruvanthapuram, also categorised as a high zone, had mask use of 85.5%, while Idukki, categorised as a “low zone” (district with cumulative caseload of less than 4,000) had the lowest mask use at 62.4%. Ernakulam and Kozhikode recorded 82.9% and 79.7% mask use respectively.
Photographs used
The study was conducted between August 28 and September 5. Using the method of photo-epidemiology, over 1,400 photographs were taken in public spaces, hospitals and at indoor gatherings, capturing 6,208 people. Around 4,500 people who were clearly visible in the photographs were used for analysis.
The average number of people per photo frame was used as a measure of physical distancing and the study found that crowding was higher in the high zone districts of Malappuram and Thiruvananthapuram, indicating that inadequate physical distancing could have contributed to a higher number of cases in these districts, despite high mask use.
“Eighty per cent proper mask use is not bad, but it is not enough, since Kerala is densely populated,” said S.S. Lal, head of public health at the Global Institute of Public Health, pointing out that there was no comparison available with other States yet.
Anand Marthanda Pillai, principal investigator of the study, said, “Overall mask usage of 96% is very high. But the 20% of people who did not use masks properly or not at all could be a loophole large enough to be concerning and spread the virus,” he said. Dr. Pillai added that a drawback of the study was that it only looked at mask use in public spaces and not in private settings like at home or at work, where mask use might be lower and the virus could spread.
