Prevalence and Pathogenic Potential of Campylobacter Isolates from Free-Living, Human-Commensal American Crows

Abstract

ABSTRACTRecent studies have suggested a potential role for wild birds in zoonotic transmission ofCampylobacter jejuni, the leading cause of gastroenteritis in humans worldwide. In this study, we detectedCampylobacterspp. in 66.9% (85/127) of free-ranging American crows (Corvus brachyrhyncos) sampled in the Sacramento Valley of California in 2012 and 2013. Biochemical testing and sequence analysis of 16S rRNA revealed that 93% of isolates (n= 70) wereC. jejuni, with cytolethal distending toxin (CDT) and flagellin A genes detected by PCR in 20% and 46% of theC. jejuniisolates (n= 59), respectively. The high prevalence ofC. jejuni, coupled with the occurrence of known virulence markers CDT and flagellin A, demonstrates that crows shedCampylobacterspp. in their feces that are potentially pathogenic to humans. Crows are abundant in urban, suburban, and agricultural settings, and thus further study to determine their role in zoonotic transmission ofCampylobacterwill inform public health.