Molecular profiling of virulent, multidrug-resistant Campylobacter jejuni isolates from broiler flocks in Ismailia, Egypt

Abstract

Objective: Campylobacter jejuni is a leading zoonotic pathogen, with broiler chickens as a primary reservoir and source of human campylobacteriosis. This study investigated prevalence, phenotypic and genotypic antimicrobial resistance, and virulence genes in C jejuni from broiler chicken samples at Egyptian slaughterhouses. Methods: 100 samples were randomly taken from slaughterhouses, comprising drippings (n = 50), neck skin (25), and cecal swabs (25). Campylobacter isolates were identified by 23S rRNA and mapA gene. Results: C jejuni was isolated from 18 of 100 samples (18%). The C jejuni isolates exhibited resistance against tetracycline (TE; 100%), amoxicillin (AMX; 83.3%), sulphamethoxazole-trimethoprim (SXT; 72.2%), and erythromycin (E; 66.7%). Meanwhile, the recovered isolates were found to be sensitive to meropenem (100%). There were 5 phenotypic resistance profiles: AMX, SXT, E, and TE (44.4%); AMX, E, and TE (22.2%); AMX, TE, and SXT (16.7%); TE and SXT (11.1%); and TE (5.6%). C jejuni strains harbored the tet(O) (100%) and blaOXA-61 (83.3%) genes. There were 2 genotypic resistance profiles, blaOXA-61 and tet(O) (83.3%) and tetO (16.7%). C jejuni harbored cadF, dnaJ, flaA, and cdtB virulence genes with a prevalence of 100%, 100%, 44.4%, and 22.2%, respectively. There were 3 virulence profiles: cadF+, dnaJ+, flaA+, and cdtB+ (22.2%); cadF+, dnaJ+, flaA+, and cdtB- (27.8%); and cadF+, dnaJ+, flaA-, and cdtB- (50%). Conclusions: Our findings demonstrate that multidrug-resistant C jejuni harboring key virulence/resistance genes in broilers is a significant concern for both public health and poultry production. Clinical Relevance: The detection of multidrug-resistant, virulent C jejuni underscores a substantial risk of carcass contamination and foodborne campylobacteriosis in humans.