Infectious Disease
Projected worldwide impact of existing and next generation respiratory and enteric vaccines on antibiotic use and bystander pathogen exposures to antibiotics among children in 129 low- and middle- income countries Stephanie A. Brennhofer* Stephanie Brennhofer Brennhofer Brennhofer Brennhofer University of Virginia
Vaccines could reduce selection pressure for antimicrobial resistance by reducing diarrhea and associated antibiotic use. We estimated the impact of existing Hib, PCV, RSV, and rotavirus vaccines, and hypothetical Shigella, Campylobacter, ETEC, norovirus, and adenovirus 40/41 vaccines on antibiotic use and antibiotic exposures to bystander pathogens among children in 129 low-resource countries.
Etiology-specific estimates of country-level incidence of antibiotic use for diarrhea were derived by combining antibiotic use data from the Demographic Health Surveys with WHO region-specific attributable fractions of diarrhea from the Global Pediatric Diarrhea Surveillance Study. Vaccine efficacy against etiology-specific antibiotic use was derived from the MAL-ED birth cohort study and applied equally across countries. Vaccine coverage was applied using averaged country-level data for rotavirus, Hib, and PCV vaccines from 2024. Bystander pathogen exposures were estimated from pathogen prevalence in asymptomatic and control stool samples from MAL-ED and the GEMS case-control study, respectively. Site level bystander pathogen data were aggregated regionally using GPDS-derived weights.
The largest reductions in antibiotic-treated respiratory illness incidence were projected to come from the existing PCV vaccine (3.87 [AMRO] to 6.72 [SEARO] episodes per 100 child years) (Figure 1), followed by the newly available RSV vaccine (3.62 [AMRO] to 6.19 [SEARO]). The largest reductions in antibiotic-treated diarrhea illness incidence were projected to come from the existing rotavirus vaccine (4.43 [AMRO] to 7.73 [SEARO] episodes per 100 child years). Projected reductions in diarrheal bystander antibiotic exposures amongst respiratory illnesses were greatest for PCV (5.75–13.19 per 100 child-years) and next for RSV (5.41–11.85). For diarrheal illnesses, the largest reductions in bystander exposures were projected from the existing rotavirus vaccine (6.57 to 15.25 per 100 child-years) with additional benefits from a simulated Shigella vaccine (0.19 to 8.68 per 100 child-years).
Existing vaccines drive the largest reductions in antibiotic use and bystander pathogen exposures, with new vaccines (e.g., RSV and Shigella) showing promise as the next high-priority target for vaccine implementation.
