Impact and management of Campylobacter in human medicine--US perspective

Antimicrobial resistance of 114 porcine isolates of Campylobacter coli

Campylobacter species were isolated from 24 pig farms in 10 different regions of Korea, and were assayed with regard to their susceptibility to eight antimicrobial agents. A total of 114 Campylobacter isolates from 572 intestinal samples were all identified as C. coli via both classical methods and molecular methods, including 16S rDNA sequence analysis and polymerase chain reactions (PCR) using specific primer sets for the hippuricase gene and the aspartokinase gene, designed to differentiate C. coli from C. jejuni. Minimal inhibitory concentrations of seven antimicrobial agents were determined via agar dilution: the MIC(90)s were 64 microg/ml for ampicillin, 8 microg/ml for chloramphenicol, 64 microg/ml for ciprofloxacin, 16 microg/ml for enrofloxacin, >or=128 microg/ml for erythromycin, >or=128 microg/ml for gentamicin, and >or=128 microg/ml for tetracycline. The proportion of isolates resistant to each antimicrobial agent was as follows: 28.9% for ampicillin, 2.6% for chloramphenicol, 84.2% for ciprofloxacin, 83.3% for enrofloxacin, 46.5% for erythromycin, 20.2% for gentamicin, and 56.1% for tetracycline. All 114 isolates were found to be resistant to at least one antimicrobial agent, and 61 isolates (53.5%) were found to be multi-drug resistant (resistant to more than three antimicrobial agents in different classes).

Does age acquired immunity confer selective protection to common serotypes of Campylobacter jejuni?

BACKGROUND

Campylobacter infection is a major cause of bacterial gastrointestinal disease. Exposure to Campylobacter is known to produce an immune response in humans that can prevent future symptomatic infections. Further, studies of the general population have shown that seroprevalence to Campylobacter increases with age.

METHODS

A large collection of serotyped Campylobacter isolates, obtained from human clinical faecal samples, were analysed by comparing the ratio of uncommon to common serotypes by different age groups, using chi2 tests.

RESULTS

We have identified that older age groups, as well as having generally lower incidence, are significantly less likely to be infected by the more common serotypes.

CONCLUSION

These results are indicative of acquired immunity, however, further studies are needed to rule out the confounding effects of the variations in exposure pathways experienced by different age groups.