Infectious Children

A study has found that younger children are more likely to spread COVID-19 in a family setting compared with older children. Specifically, children 3 or younger were more likely to spread the virus to household members compared with those aged 14 to 17.

The study, published in JAMA, analyzed public health data from Ontario, Canada, to identify COVID clusters in which a child was the primary case within households.

Earlier in the pandemic, some scientists suggested the risk of transmission declined with younger children. But this assumption was likely skewed by the fact that lockdowns and social distancing meant young children had very few social encounters.

The study involved 6,280 households with COVID-19 index patients 17 years and younger from Jun 1 to Dec 31, 2020, prior to the emergence of the Delta Variant, so more research is needed to understand transmission risk in the context of the variant. The study also took place prior to vaccines being available, meaning all household members were unvaccinated.

Babies and toddlers are probably more likely to spread disease to parents and caregivers because they are cared for directly, in close contact. “The 0-to-3-year-old child is held differently, is cuddled,” said Dr. Paul Offit, director of the Vaccine Education Center and professor of pediatrics in the Division of Infectious Diseases at Children’s Hospital of Philadelphia. The risk of death and severe illness is still much lower in younger children compared with older children and adults. The best line of defense against further spread of the virus is for the parents of the child to both be vaccinated.

This study reinforces the importance of existing mitigation strategies at childcare facilities and schools, including distancing, good ventilation, frequent cleaning and masking whenever possible. t also reinforces the importance of all eligible people over 12, especially those around young children, getting vaccinated.