Smokers, vegetarians at lesser risk of getting infected by coronavirus: CSIR Survey
The survey also found that those with blood group 'O' may be less susceptible to the infection, while people with 'B' and 'AB' blood groups were at a higher risk.
According to a pan-India serosurvey conducted by the Council of Scientific and Industrial Research (CSIR), Smokers and vegetarians were found to have lower seropositivity indicating that they may be at a lesser risk of getting infected by coronavirus. The survey was conducted across CSIR's nearly 40 institutes.
The survey also found that those with blood group 'O' may be less susceptible to the infection, while people with 'B' and 'AB' blood groups were at a higher risk. In order to assess the presence of antibodies to SARS-CoV-2, the Scientific and Industrial Research Council (CSIR) took samples of 10,427 adult individuals working in its laboratories or institutions and their family members on the basis of voluntary participation.
The study which was piloted by CSIR-Institute of Genomics and Integrative Biology (IGIB), Delhi said of the 10,427 individuals, 1,058 (10.14%) had antibodies against SARS-CoV-2.
In July last year, the Ministry of Health of the Union reported that smokers were likely to be more vulnerable to Covid-19, as smoking increases the risk of virus transmission from hand to mouth, and cautioned that smoking tobacco products may increase the severity of respiratory infections and render people susceptible to coronavirus.
However, the study suggested that smokers are less likely to be seropositive and despite Covid-19 being a respiratory disease, smoking may be protective.
“The study found that higher seropositivity was found for those using public transport and with occupational responsibilities such as security, housekeeping personnel, non-smokers, and non-vegetarians.” “Use of private transport, lower-exposure occupations, smoking, vegetarianism, and ‘A’ or ‘O’ blood groups appeared to be protective, using seropositivity as a surrogate for infection,” the paper added.
A repeat sampling of 35 individuals, at six months, revealed declining antibody levels while the neutralising antibody remained stable compared to three months. However, both the normal antibody as well as the neutralising antibody were much above the required threshold, Shantanu Sengupta, senior scientist at IGIB and one of the co-authors of the paper said.
Our finding that smokers are less likely to be seropositive is the first report from the general population and part of growing evidence that despite COVID-19 being a respiratory disease, smoking may be protective, the study said. The paper also cites two studies from France and similar reports from Italy, New York and China, which reported lower infection rates among smokers.