Rates of fluoroquinolone resistance in domestically acquired campylobawecter jejuni are increasing in people living within a model study location in canada

Citation

Inglis, G.D., Taboada, E.N., Boras, V.F. (2021). Rates of fluoroquinolone resistance in domestically acquired campylobawecter jejuni are increasing in people living within a model study location in canada. Canadian Journal of Microbiology, [online] 67(1), 37-52. http://dx.doi.org/10.1139/cjm-2020-0146

Plain language summary

We examined temporal changes in resistance to antibiotics in clinical isolates of Campylobacter jejuni over a 15 year period within a model location in Canada (i.e. 1,291 infected people from 2004-2018). Resistance to medically important fluoroquinolone antibiotics (e.g. ciprofloxacin) increased ten times during the study period, peaking at ≈30%. An examination of fluoroquinolone resistant (FQR) isolates indicated that 94% contained a C257T mutation within the gyrA chromosomal gene. The majority of infections with FQR C. jejuni isolates were determined to be domestically acquired, and primarily by subtypes that are prevalent in beef cattle, but also found in poultry reservoirs. Although fluoroquinolone use is restricted in cattle and poultry production in Canada, our study findings suggest that the mechanisms of FQR emergence and transmission are complex. Moreover, the study illustrates the value of applying a regional ‘One Health’ approach to elucidate the epidemiology of antibiotic resistance in C. jejuni.

Abstract

Antimicrobial resistance was evaluated in Campylobacter jejuni isolated from 1291 diarrheic people over a 15-year period (2004–2018) in southwestern Alberta, a model location in Canada with a high rate of campylobacteriosis. The prevalence of resistance to chloramphenicol, clindamycin, erythromycin, and gentamicin was low during the examination period (≤4.8%). Resistance to tetracycline remained consistently high (41.6%–65.1%), and resistance was primarily conferred by plasmid-borne tetO (96.2%). Resistance rates to ciprofloxacin and nalidixic acid increased substantially over the examination period, with a maximal fluoroquinolone resistance (FQR) prevalence of 28.9% in 2016. The majority of C. jejuni isolates resistant to ciprofloxacin (93.9%) contained a C257T single nucleotide polymorphism within the gyrA chromosomal gene. Follow up with infected people indicated that the observed increase in FQR was primarily due to domestically acquired infections. Moreover, the majority of FQ-resistant C. jejuni subtypes (82.6%) were endemic in Canada, primarily linked to cattle and chicken reservoirs; 18.4% of FQ-resistant isolates were assigned to three subtypes, predominantly associated with cattle. Study findings indicate the need to prioritize FQR monitoring in C. jejuni infections in Canada and to elucidate the dynamics of the emergence and transmission of resistant C. jejuni strains within and from cattle and chicken reservoirs.

Publication date

2021-01-01