India’s low hygiene improves immunity against COVID-19: CSIR study

NEW DELHI: A new paper by Centre of Scientific and Industrial Research (CSIR) states that the country’s minimal levels of hygiene have likely helped Indians fight COVID-19. The study, which is pending peer-review, says that high parasite and bacterial disease burden in “low and middle income countries” has led to improved immunity in its citizens against the novel coronavirus. Moreover, the chronic exposure to communicable diseases has led to “immunity training” to fight COVID-19 infection.

The study is based on ‘immune hypothesis’, which means that better hygiene and less exposure to infection in developed countries has resulted in autoimmune disorders and allergies. This autoimmune is a risk factor in COVID-19 as because of it, the body creates cytokine storm, which is the main cause of deaths.

The research included publicly available data from 106 countries, including deaths per million due to COVID-19 infection, Gross Domestic Product (GDP), sanitation data, etc. The fact that Bacille Calmette-Guerin (BCG) vaccine for Tuberculosis has a role to play in bettering immunity in citizens of  poor nations was also examined. However, no co-relation is found between BCG vaccines and lower death rates.

A large population with non-COVID disorders such as diabetes, hypertension, etc live in countries with a high Human Development Index. Due to this, co-morbidities might have emerged as important determinants of Case Fatality Rate (CFR).