Catching a cold may help to protect children from the worst effects of Covid by boosting their immune system, according researchers at Yale University which analysed more than 600 nasal swabs taken from children about to undergo surgery or evaluation in A&E in 2021 and 2022. After testing samples for Covid and 19 different respiratory viruses and bacteria and then measured the levels of antiviral and inflammatory proteins produced by the children’s immune system, they found that many children infected with respiratory pathogens other than Covid, including Rhino viruses responsible for the common cold.

Children with higher levels of respiratory pathogens showed higher immune activity in the nose, suggesting their antiviral defences were on high alert and more equipped to fight off Covid.