Antimicrobial resistance in nontyphoidal Salmonella associated with multistate outbreaks linked to backyard poultry, United States, 2018–2023

Résumé

Introduction State and local health departments and the Centers for Disease Control and Prevention (CDC) routinely investigate multistate outbreaks of salmonellosis associated with backyard poultry (BYP). Here, we describe antimicrobial resistance in multistate outbreaks of nontyphoidal salmonellosis associated with BYP from 2018 to 2023. Methods We analyzed patient and outbreak data from CDC’s National Antimicrobial Resistance Monitoring System and System for Enteric Disease Response, Investigation, and Coordination databases. Isolate resistance was determined by antimicrobial susceptibility testing or predicted by whole genome sequencing. We classified isolates as resistant, multi-drug resistant (MDR; resistant to ≥3 antimicrobial classes), or having clinically relevant resistance (CRR; resistant to ampicillin, azithromycin, ceftriaxone, or trimethoprim-sulfamethoxazole; or nonsusceptibility to ciprofloxacin), and outbreaks as resistant, MDR, or CRR if ≥3 isolates and ≥10% of isolates met the corresponding resistance definitions. Statistical analyses comparing patient variables, outbreak size, and annual number of outbreaks with resistance status were performed. Results Among 78 multistate BYP-associated salmonellosis outbreaks, 36 (46%) exhibited resistance, 10 (13%) were classified as MDR, and 12 (15%) were classified as CRR. Enteritidis was the most frequent serotype, causing 22 (28%) outbreaks; three were resistant (two CRR only outbreaks, one CRR and MDR outbreak). Among the 6,262 patient isolates included in multistate BYP-associated salmonellosis outbreaks, 2,248 (36%) were resistant, 209 (3%) were MDR, and 395 (6%) were CRR. Discussion Although nearly half of BYP-associated salmonellosis outbreaks and one-third of outbreak isolates were resistant, CRR and MDR outbreaks and isolates were infrequent. Continued monitoring for antimicrobial resistance is warranted because of the persistence of BYP-associated salmonellosis and the potential for BYP to serve as a reservoir for resistant Salmonella that can spread to people.

Citer ce document

Accès au document

Texte intégral en lecture en ligne, réservé aux abonnés SPHAERO et aux membres de l'institution. Se connecter

Auteur(s)

Statistiques

Consultations : 1

Téléchargements : 0