Children between the age of 5 and 17 are the most exposed cohort to the coronavirus in New Delhi, according to a serological survey, PTI reported on Tuesday. A prevalence rate of 34.7% was found among the age group concerned, the survey showed.

The survey also revealed that 29.1% of Delhi’s population has developed antibodies against the infection.

The survey, the second in the city, was conducted between August 1 and August 7. Around 15,000 people from four age groups participated in the survey. Nearly 25% were below 18 years, 50% between ages 18 and 50 and the remaining were more than 50 years old.

It showed that 34.7% of those aged between 5 and 17 years had antibodies, while the figure was 31.2% for the participants above 50 years, and 28.5% for those in the 18-49 age bracket, The Print reported.

According to the US’ Centers for Disease Control and Prevention, serology tests are “those that look for antibodies in blood”. “If antibodies are found, that means there has been a previous infection,” it says. “However, there is a chance a positive result means that you have antibodies from an infection with a virus from the same family of viruses (called coronaviruses), such as the one that causes the common cold.”

Serological surveys reveal how many people may have been infected with the novel coronavirus in an area but they do not show how many people are immune to the virus. It still isn’t clear how long antibodies last in infected persons and how many antibodies are needed to protect a person from reinfection.

Experts said that children may be getting infected through adults in the house.

“It is difficult to keep children and youngsters home-bound,” Dr Mahesh Verma, head of a Delhi government committee formed to evaluate the preparedness of hospitals to battle the coronavirus, said. “Even if they are not going to school, they might be going out to play... or they might have contracted it through an indirect route. But it’s just a prediction and needs to be studied.”

Verma also said that it was complex to find out how people were getting infected, adding that he knew families that have stayed home and still contracted the virus.

Dr Gauri Aggarwal, the founder of Seeds of Innocence and Genestrings Lab, believed that the children might have been infected by someone in the family who regularly stepped out.

The serological survey also showed that 31.2% of people aged above 50 had recovered from the Covid-19 infection.

The Delhi government was waiting for the district-wise breakdown of the data from the Maulana Azad Medical College so that it can examine the results in detail, according to The Print. Two more rounds of the survey are scheduled to be held in the first weeks of September and October.

Earlier, a similar serological survey conducted in Delhi had shown that 23.8% of the respondents carried antibodies. The results of the Delhi survey, which was revealed in July, implied that the total number of cases in the Capital should be around 47 lakh in relation to the city’s population of two crore.

As of Tuesday, Delhi has reported 1,62,527 Covid-19 cases and 4,313 related deaths, according to the health ministry. India’s coronavirus tally rose to 31,67,323 cases after the country reported 60,975 new infections in 24 hours. The country’s toll rose by 848 to 58,390, according to the Union health ministry data.

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