According to the largest contact tracing study in India, the transmission of COVID-19 in the country has largely been by ‘super spreaders’ or a small percentage of infected people. Interestingly, the study also shows that children are key to the spread of the novel coronavirus.

The study, published in the journal Science on Wednesday, assessed the pattern of disease transmission in 5,75,071 individuals exposed to 84,965 confirmed cases of COVID-19 in Tamil Nadu and Andhra Pradesh, based on data collected by tens of thousands of contact tracers.

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Researchers, including those from the government of two states, have found that more than 70% of COVID-19 infected patients in the country did not infect their contacts, while 8% of the virus-carriers accounted for the 60% of observed new infections.

Adding to this, researchers also found a high infection rate among children who were in contact with other cases around their own age.

Informing about the deaths due to COVID-19, the study shows that it has been more heavily concentrated in the 40-69 year age group than is seen in high-income countries, among other trends.

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Based on the data, the scientists said both cases and deaths in the two Indian states were concentrated in youngsters.

The study noted that contacts with the same age were associated with the greatest infection risk — a pattern, which the researchers said, was strongest among children between 0-14 years of age, and among adults older than 65 years.

The research mentioned that 63% of those who died had at least one co-morbidity, and 36% had two or more underlying health conditions that made them more susceptible to the disease.

About 45% of those who died were diabetic, the scientists said.

India has emerged as the second-worst hit nation by COVID-19. Currently, there are 940,705 active cases in the country, while 5,273,202 have recovered/discharged.