Study Overview in Guatemalan Children
IN THIS cross-sectional community-based study, investigators assessed whether routine pneumococcal vaccination and rotavirus vaccination influence colonization with extended spectrum cephalosporin resistant Enterobacterales in children younger than 15 years in Guatemala. Researchers collected questionnaire data, vaccine records, and stool samples from 406 participants aged 0 to 14 years, then cultured specimens on selective media and confirmed antibiotic susceptibility using an automated system. They applied an instrumental variables framework with three nested probit models to explore direct and indirect pathways between vaccination, healthcare use, diarrhea, and ESCrE colonization.
Pneumococcal Vaccination and ESCrE Colonization
Pneumococcal vaccination with PCV13 was associated with a lower probability of ESCrE colonization that appeared to be mediated through reduced clinic visits. In the models, pneumococcal vaccination had an indirect protective effect on ESCrE colonization, while antibiotic use increased clinic visits but did not show significant direct or indirect effects on ESCrE carriage. Effects of rotavirus vaccination on ESCrE colonization were inconclusive, most likely because relatively few enrolled children lacked rotavirus vaccination, which limited statistical power.
Complex Drivers of Antibiotic-Resistant Bacteria
Beyond vaccination, several contextual and behavioral factors were associated with ESCrE colonization. Recent diarrhea was linked to a higher risk of colonization and may reflect disruption of gut flora and increased healthcare contact. Yogurt consumption showed a modest protective association with ESCrE colonization in both pneumococcal vaccination and rotavirus vaccination models. In contrast, living in households that used land for agriculture was directly associated with a higher probability of colonization, highlighting possible environmental reservoirs of antibiotic-resistant bacteria. Overall, the analysis reinforces that antimicrobial resistance in Enterobacterales arises from a complex interplay between vaccination, infection burden, care seeking, antimicrobial exposure, diet, and environmental factors. The authors note that these findings should be confirmed in larger studies designed to capture clinical outcomes as well as colonization status.
Reference: Ramay B M et al. Assessing effects of pneumococcal vaccination (PCV13) and rotavirus vaccination (RV) on colonization with extended-spectrum cephalosporin-resistant Enterobacterales (ESCrE) in Guatemalan children. Vaccine. 2025;66:127852.
