Written by Hannah Harp
Spoon Feed
Respiratory tract infections (RTI) decreased with COVID-19 precautions, but rose following discontinuation, suggesting an “immune debt” due to naivety to pathogens and reduced immunity.
Paying off their debts
Childhood RTI dropped drastically during the COVID-19 pandemic, ostensibly because of “non-pharmaceutical interventions” (NPIs), a.k.a. public health measures like masking, social distancing, isolation, and quarantine. When these were lifted, there was an outsized surge in pediatric RTI that is poorly understood.
This study examined the impact of these NPIs during COVID-19 on the incidence of five pediatric RTIs and the subsequent rebound following their removal. A multinational, interrupted time-series analysis was conducted using data from 528,055 pediatric emergency department visits across 13 European countries. During the NPI period (4/1/20 – 3/31/21), RTIs declined significantly compared to the pre-NPI period (1/1/18 – 3/31/20): pneumonia (-76%), bronchiolitis (-69%), croup/laryngitis (-66%) pharyngitis/tonsillitis (-65%), AOM (-65%). Following NPI lifting (4/1/21 – 6/30/22), RTIs rebounded substantially: pneumonia (+220%), bronchiolitis (+329%), croup/laryngitis (+130%), pharyngitis/tonsillitis (+83%), AOM (+168%). UTI cases were used as a control, which did not change significantly. A strong “dose-response” relationship was observed for all 5 RTIs. This correlation was also significant when stratified for viral cases, upper RTIs, lower RTIs, hospitalized cases, and non-hospitalized cases.
The authors consider this dose-dependent correlation supportive of “immune debt” as a cause of the RTI resurgence. While the correlation is significant, this observational study cannot prove causation. Also, this study did not look at specific pathogens, and there could be other factors, such as changes in health-care-seeking behaviors and immunization uptake, playing a role as well.
How will this change my practice?
While this study won’t change my practice individually, it provides useful information from a public health standpoint, and informs NPI policies and preparedness for an onslaught of illness after another pandemic (which hopefully won’t be anytime soon).
Source
Surge of Pediatric Respiratory Tract Infections After the COVID-19 Pandemic and the Concept of “Immune Debt”. J Pediatr. 2024 Nov 21:114420. doi: 10.1016/j.jpeds.2024.114420. Epub ahead of print. PMID: 39579868
