Waning infant pertussis during COVID-19 pandemic

Area of Science:

• Public Health
• Infectious Diseases
• Epidemiology

Background:

• Non-pharmaceutical interventions (NPIs) for COVID-19, such as social distancing and mask mandates, were implemented globally.
• These measures aimed to reduce respiratory virus transmission, but their impact on other specific infections was not fully elucidated.
• Pertussis (whooping cough) is a highly contagious respiratory illness that affects infants.

Purpose of the Study:

• To investigate the impact of COVID-19 pandemic control measures on the incidence of pertussis in infants.
• To compare pertussis rates in infants before and during the COVID-19 pandemic in Sweden.

Main Methods:

• A national cohort study was conducted in Sweden.
• Infant pertussis cases from April 2020 to September 2021 (during the pandemic) were compared with data from January 2014 to March 2020 (pre-pandemic).
• Quarterly incidence rates of infant pertussis were analyzed.

Main Results:

• A significant decrease in infant pertussis cases was observed during the COVID-19 pandemic.
• The average number of infant pertussis cases per quarter dropped from 21 before the pandemic to 1 during the pandemic.
• This represents a substantial reduction in pertussis incidence.

Conclusions:

• Swedish public health strategies implemented to mitigate COVID-19 spread were associated with a significant reduction in infant pertussis.
• The findings suggest that broad public health interventions can effectively control other vaccine-preventable respiratory infections.
• Further research may explore the long-term effects and specific mechanisms of NPIs on pertussis transmission.