Revelation consistent with findings of different studies done in the US, the UK, France, Italy and China
A recent survey conducted by Council of Scientific Industrial Research (CSIR), Government of India, has revealed that smokers and vegetarians are less likely to contract COVID-19 infection. The survey suggested smoking may be protective, despite COVID-19 being a respiratory disease, due to its role in increasing the mucous production that may be acting as the first line of defence among the smoking population. It indicated that vegetarian food rich in fibre may have a role to play in providing immunity against COVID-19 due to its anti-inflammatory properties by modification of gut microbiota.
The pan India survey was conducted by an eminent team of 140 doctors and research scientists to study the presence of antibodies against SARS-CoV-2, the virus that causes COVID-19, and their neutralisation capability to infer possible risk factors for infection. The study assessed 10,427 adult individuals working in more than 40 CSIR laboratories and centres in urban and semi-urban settings spread across and their family members. These people voluntarily participated in the study.
Earlier, two studies from France and similar reports from Italy, New York, and China reported lower Covid infection rates among smokers. A study by America’s Centers for Disease Control and Prevention (CDC), which examined over 7,000 people who tested positive for COVID-19, also vindicated the above findings. Interestingly, the study found that only 1.3 per cent of survey participants were smokers, compared to the CDC report that 14 per cent of all Americans smoke.
Similarly, UCL (University College London) academics that looked at 28 papers across the UK, China, US, and France found the proportions of smokers among hospital patients were ‘lower than expected. One of its studies showed that in the UK the proportion of smokers among COVID-19 patients was just five per cent, a third of the national rate of 14.4 per cent. Another found in France the rate being four times lower (7.1 per cent vs 32 per cent among all population). In China, a study noted that only 3.8 per cent of patients were smokers – despite more than half of the population regularly smoking cigarettes.
In a separate study by Jin-jin Zhang to understand the influence of smoking behaviour on the susceptibility to Coronavirus observed that only 9 (6.4 per cent) patients had a history of smoking, and seven of them were past smokers. The study found that smoking populations were less likely to be infected with SARS-CoV-2. These findings were also confirmed by a French study of public health data that showed people who smoke, were 80 per cent less likely to fall prey to COVID-19 than non-smokers of the same age and sex.