Coronavirus India: Most COVID-19 cases transmitted by super spreaders, finds study

Coronavirus India: Most COVID-19 cases transmitted by super spreaders, finds study 

Even as India battles one of its deadliest pandemics yet, the trajectory of cases in India has puzzled experts. Despite having a good recovery rate, a declining ‘R’ number and low mortality rate as compared to other nations, we are yet to reach the proper peak of the pandemic.

The study

A contact tracing study, which has been published in the journal Science found that of all the recorded cases, nearly 70% of those identified, did not pass on the infection onto others, but 8% of those surveyed were responsible for causing 60% of new infections in the country.

While constant steps are being taken to control the pandemic, new studies have revealed that a big surge in the cases could be because of the presence of super-spreaders in the country.

The study was based out of two states, Tamil Nadu and Andhra Pradesh, which have been recording high COVID spikes in the past months. Researches worked to observe disease transmission patterns in 5,75,071 who were exposed to 84,965 confirmed COVID cases in the two states.

The 8% of people referenced here are called super spreaders. According to the World Health Organisation, superspreaders are the ones who spread the infectiom onto others, at a large scale. These can also include silent spreaders. According to scientific monitoring tools, it means that if 80% of new transmissions are caused by fewer than 20% of the carriers, those will be referred to as the super spreader category.

Super spreaders could also be the reason why some COVID-19 carriers spread the disease onto so many, while some do not spread the disease to others.

Given the wide population base of India, the study on the presence of super-spreaders in India could showcase why so many positive cases are being witnessed in the country, despite the activation of lockdowns and phased closings and reopenings.

Interestingly, the study also showcased how children might be silently contributing to the spread of the disease in our country. While most schools still remain closed down and fewer cases of COVID-19 recorded amongst children, the research identified that kids aged 14 and below were silently acting as the carriers of the disease and spreading it amongst their contacts.

Ramanan Laxminarayan, a disease expert, who authored the study said, “This shows that even without schools being functional, children-to-children transmission seems to be quite important.”

Previous studies conducted in countries like Korea, China and the US have also showcased how children can act as silent spreaders of the infection, spread the virus for upto three weeks time, even if they are asymptomatic.

Experts have also been stressing that opening up of schools and colleges right now, or public areas could only contribute to further growth spurts like this.

The case mapping also revealed the age-wise division of COVID cases in the country. It was observed that in the two states, the age group 40-69 was the most adversely affected by the virus, and suffered the highest rates of infections as well as mortality.

The research also threw light at the dangers of co-morbidities in hospitalization and mortality rates in COVID cases. According to the study, 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 infection.

A whopping 45% death rate was observed amongst those found to have uncontrollable diabetes.

Public places contribute to spread

Following graded unlocks, public transport facilities, like buses, metros have resumed services. While superspreaders were responsible for the highest spike in case transmission, the research identified that there was a 79% infection chance on people using public transport.