Search

Australian rates of campylobacteriosis are among the highest in developed countries, yet only limited work has been done to characterize Campylobacter spp. in Australian retail products. We performed whole genome sequencing (WGS) on 331 C. coli and 285 C. jejuni from retail chicken meat, as well as beef, chicken, lamb and pork offal (organs). Campylobacter isolates were highly diverse, with 113 sequence types (STs) including 38 novel STs, identified from 616 isolates. Genomic analysis suggests very low levels (2.3-15.3%) of resistance to aminoglycoside, beta-lactam, fluoroquinolone, macrolide and tetracycline antibiotics. A majority (>90%) of isolates (52/56) possessing the fluoroquinolone resistance-associated T86I mutation in the gyrA gene belonged to ST860, ST2083 or ST7323. The 44 pork offal isolates were highly diverse, representing 33 STs (11 novel STs) and harboured genes associated with resistance to aminoglycosides, lincosamides and macrolides not generally found in isolates from other sources. Prevalence of multidrug resistant genotypes was very low (<5%), but ten-fold higher in C. coli than C. jejuni. This study highlights that Campylobacter spp. from retail products in Australia are highly genotypically diverse and important differences in antimicrobial resistance exist between Campylobacter species and animal sources., Competing Interests: The authors whose names are listed immediately below certify that they have NO affiliations with or involvement in any organization or entity with any financial interest (such as honoraria; educational grants; participation in speakers’ bureaus; membership, employment, consultancies, stock ownership, or other equity interest; and expert testimony or patent-licensing arrangements), or non-financial interest (such as personal or professional relationships, affiliations, knowledge or beliefs) in the subject matter or materials discussed in this manuscript. Author Names: Rhiannon L. Wallace, Dieter M. Bulach, Amy V. Jennison, Mary Valcanis, Angus McLure, James J. Smith, Trudy Graham, Themy Saputra, Simon Firestone, Sally Symes, Natasha Waters, Anastasia Stylianopoulos, Martyn D. Kirk, Kathryn Glass* AgriFutures is the only commercial entity that provided funding for this study. This does not alter our adherence to PLOS ONE policies on sharing data and materials. All other funding was from NHMRC and various government departments, all of which have now been mentioned in the funding statement.

Traditionally group B streptococcus (GBS) has not exhibited resistance to the antibiotics penicillin and erythromycin. Recently there are reports from North America whereby some GBS isolates have exhibited resistance to erythromycin. There have been no studies reported to date to determine whether this resistance trend is also occurring in the Australian population. Over a period of six months from January to June 1999, 250 GBS isolates were collected at the Royal Women's Hospital, Melbourne. Sensitivity to penicillin, erythromycin and vancomycin was determined by disk diffusion. Any isolates that had reduced zones to penicillin, vancomycin or erythromycin had minimum inhibitory concentrations (MIC) determined. No isolates had reduced susceptibility to penicillin or vancomycin. Of the 250 isolates, seven (2.8%, 95% CI = 1.1-5.6%) had resistant MICs to erythromycin of > 1.0 microg/mL. These preliminary data suggest that penicillin therapy is still an effective first-line antibiotic for intrapartum chemoprophylaxis and that erythromycin resistance is low in our population.