Kids have 56% lower chance of catching Covid-19 infection: Study

In a finding that has implications for the reopening of schools, a new study has found that children and teenagers carry about half the risk that adults do of being infected by Sars-CoV-2, the virus that causes the coronavirus disease (Covid-19). It is still not clear whether children are also less likely to spread the infection to others.

Children are 56% less likely than adults to get infected by the virus when they come in contact with an infected person, according to the study by researchers at the University College London, which was published in the preprint journal medRxiv. The study has not yet been peer-reviewed.

“There is preliminary evidence that children and young people have lower susceptibility to Sars-CoV-2, with 56% lower odds of being an infected contact. There is weak evidence that children and young people play a lesser role in transmission of Sars-CoV-2 at a population level. Our study provides no information on the infectivity of children,” said the report, which analysed data from 6,327 studies that had been published till May 16, 2020.

The role of children and young people in spreading the disease depends on several factors, including their susceptibility to infection, severity of symptoms, viral load, social contact patterns, and risk behaviour. Clinical series and testing of symptomatic cases alone gives biased estimates of susceptibility in children, who often don’t develop symptoms.

“The susceptibility of children to Sars-Cov2 is low, according to most of the information. If they are asymptomatic, as most are, transmission risk will be very low,” said Dr K Srinath Reddy, president, Public Health Foundation of India.

Studies on Covid-19 prevalence in children have produced widely varying results, noted the University College London analysis. Large studies from Iceland, the Netherlands and Spain and Italy showed markedly lower Sars-CoV-2 prevalence among children and young people, but studies from Sweden, England and some cantons in Switzerland and Germany found no difference in infection prevalence between adults and children.

The Swedish Public Health Agency found 4.7% antibody prevalence in children and teenagers, compared with 6.7% in adults aged 20 to 64, and 2.7% in 65- to 70-year-olds.

“Long-lasting school closures not only lead to a loss of learning but the isolation also harms their mental health and social development, so we have to consider whether the harm outweighs the infection risk for children, who can spread it to their families, school staff and the community,” said Dr Rajesh Sagar, professor in the department of psychiatry, All India Institute of Medical Sciences.

Most schools in India have been closed since March 21, the weekend before a national lockdown was announced by Prime Minister Narendra Modi on March 24.

Unlike Sweden, which kept day care centres and schools through the ninth grade open without major adjustments to class size, lunch policies, or recess rules, schools in India are unlikely to open before July as the authorities attempt to lower children’s exposure to the risk of infection.

“Most young children find it difficult to follow social distancing norms and given the large number of students in one classroom, and crowded transport and playgrounds, schools can easily turn into infection clusters if children infect teachers or take the infection to their family and neighbourhood even if they don’t get severe disease themselves,” said Dr Sagar, who specialises in child mental health.

Socially- and economically disadvantaged children who depend on schools for midday meals, education, nutrition and health are among the worst hit by prolonged school closure.

“School provides a structured setting in which children can learn and develop social competencies, such as self-confidence, friendship, empathy, participation, respect, gratitude, compassion, and responsibility. Social and emotional learning is important for young people to become conscious members of a solidarity-based community,” according to a paper on rethinking the role of the school after Covid-19, published in The Lancet.

A hybrid model of education with greater dependence on e-learning is being used in many countries that are reopening schools post lockdown, but it has its challenges. “Since all children do not have access to online learning because of uneven access, teaching using radio and television should be considered as that group cannot be ignored,” Dr Sagar said.