[Frecuency of Bordetella pertussis infection in adults: a multicenter study in Argentina].

INTRODUCTION

The epidemiology of Bordetella pertussis (Bp) has changed following universal pediatric vaccination, with an increase in cases among adolescents and adults, who may have a higher risk of complications and behave as a reservoir for infection in infants. Reported prevalence in adults ranges from 2% to 32% worldwide. The aim of this study was to assess the frequency of Bp infection in adults with cough in Argentina.

MATERIALS AND

METHODS

This was a prospective, multicenter, observational cross-sectional study conducted between August 2023 and August 2024, including individuals aged =50 years with cough lasting 3-28 days who presented to outpatient clinics at four hospitals in Argentina. Nasopharyngeal swabs were collected and analyzed using multiplex PCR (FilmArray BioFire RP2.1, Biomérieux). Clinical and epidemiological data were collected at baseline and through telephone follow-up at 7 and 30 days.

RESULTS

A total of 391 participants were included. Nasopharyngeal swab positivity was 65% (n=255), significantly higher among individuals with <7 versus =7 days of cough at presentation (75% vs. 56%, p<0.001). Bp was detected in 1 of 391 individuals (0.3%; 95% CI 0.036%- 1.8%). In addition, 284 viruses and 8 bacteria were identified, including 34 coinfections (13%). The hospitalization rate was 5.6% and was significantly associated with the presence of comorbidities at presentation (OR 5.86; 95% CI 1.87-18.33; p=0.002).

CONCLUSION

Detection of Bp was low, with viral pathogens predominating and complications occurring mainly in patients with comorbidities. Future studies with broader population, geographic, and temporal coverage may detect a higher frequency of this cyclically circulating pathogen.