Abstract

Background Restrictive measures were widely introduced at the start of the COVID-19 pandemic to reduce the spread of the virus. These restrictions have been linked to reductions in laboratory-diagnosed infections and hospitalisations. It is unclear if the observed decreases reflect a reduction in health-seeking behaviour or results from fewer infections per se. Methods We have explored trends in caregiver reports of respiratory infections and symptoms needing a doctor visit in children aged 0–11 years using data from the New Hampshire Birth Cohort Study in 2011–2021, comparing the prepandemic and pandemic periods. Generalized Estimating Equations were used to model pandemic/prepandemic risk ratios (RRs) with adjustment for maternal and child characteristics. Results The overall probability of a report of an upper respiratory tract infection (RTI) needing a doctor visit in children aged 0–11 years was 16.7%. There was strong evidence of a decline during the pandemic: 17.9% pre pandemic versus 8.19% in the pandemic period, adjusted RR 0.51 (95% CI: 0.42 to 0.64). Similar trends were seen for any lower RTI, any respiratory symptom and any other acute symptom with overall probabilities of 4.33%, 24.8% and 13.8%, respectively, and adjusted rate ratios 0.61 (0.41 to 0.91), 0.59 (0.51 to 0.68) and 0.72 (0.59 to 0.87), respectively. In contrast, respiratory syncytial virus and bronchiolitis remained steady. Conclusions The steep decline in caregiver-reported infections and symptoms mirrored trends reported in laboratory-diagnosed infections and hospitalisations and suggests a real decrease in prevalence. Longer follow-up is needed to determine later consequences of the reduction in childhood infections.