Rethinking pneumococcal surveillance through indoor air sampling.

BACKGROUND

Pneumococcal surveillance remains challenging due to limited invasive disease surveillance and logistically demanding nasopharyngeal carriage studies, particularly in low- and middle-income countries (LMICs). We evaluated indoor air sampling as a noninvasive approach for monitoring pneumococcal circulation and serotype distribution.

METHODS

Monthly indoor air samples were collected over 20 months (January 2022-September 2023) in a Belgian childcare center. Samples were analyzed by qPCR for pneumococcal detection and serotype identification.

RESULTS

Pneumococci were detected in all samples. After excluding serotypes with known specificity issues, 15 serotypes/serogroups were identified, with a mean of seven per sample. Commonly detected serotypes largely matched those reported in Belgian carriage studies and invasive disease surveillance.

CONCLUSIONS

Indoor air sampling captured signals of community pneumococcal circulation and serotype dynamics. With further validation, it could provide a scalable, affordable surveillance tool to support vaccine policy, monitor vaccine impact, and strengthen respiratory pathogen surveillance, particularly in LMICs.