Characterization of Campylobacter Isolates Recovered from Clinically Healthy Pigs and from Sporadic Cases of Campylobacteriosis in Humans

Abstract

Campylobacter spp. were recovered from 660 (77.6%) of 850 swine cecal contents at the abattoir and from 24 (8.6%) of 278 specimens from sporadic cases of human diarrhea during the same period in the same geographical area. Campylobacter coli represented 95.7% of Campylobacter isolates recovered from pigs and 8.3% of those isolated from humans. Genetic profiles were determined by pulsed-field gel electrophoresis (PFGE) using KpnI enzyme to characterize the isolates in combination with phenotypic assays to detect production of cytotoxins, enterotoxins, and hemolysins. Among a subset of isolates (n = 10), up to five colonies from the same animal were characterized by PFGE. In 5 (50%) of 10 of the isolates, more than one genetic profile was observed per pig. Among the 100 isolates from pigs selected for further analysis, 81 different genetic profiles were observed, whereas 20 different genetic profiles were found among the 24 isolates of human origin. Cytotoxicity on Chinese hamster ovary cells was observed in 11 (11%) of 98 isolates from pigs and in 5 (21%) of 24 Campylobacter isolates from humans. No enterotoxin production was detected in Campylobacter isolates in this study, but 17 (71%) of 24 human and 61 (63%) of 97 pig isolates showed hemolytic activity. The study of genotypic and phenotypic profiles of swine and human isolates revealed no epidemiological relationship between isolates. The low genomic relatedness observed between groups of isolates and the weak toxicity level of swine isolates suggest that the hazard of contamination of humans by Campylobacter associated with swine production is low.

The occurrence and characterization of Campylobacter jejuni and C. coli in organic pigs and their outdoor environment

“…For example, up to five different serotypes out of five bacterial isolates were obtained, which is in accordance with the high strain diversity found in pigs in other studies (Weijtens et al, 1997;Moore et al, 2002;Guevremont et al, 2004;Alter et al, 2005;Boes et al, 2005). Even though a certain serotype seemed to dominate in a pig one week, it was not necessarily isolated from this pig the following weeks.…”

“…Although some of these C. coli serotypes (e.g. O:30) also have been found in human cases of campylobacteriosis, no epidemiological relationship has been found between pig and human C. coli isolates Guevremont et al, 2004;Siemer et al, 2005).…”

Prevalence of Campylobacter subtypes in pheasants (Phasianus colchicus spp. torquatus) in the Czech Republic

“…On the other hand, many C. jejuni strains have been shown to remain genetically stable (Manning et al, 2001). For these reasons some authors describe common genotypes in groups of animals raised simultaneously on the same farm (Guevremont et al, 2004), others have reported that broiler flocks can be colonized by 1-3 and parent flocks by 2-6 different Campylobacter clones. Rather than exclusive colonisation, clones coexist within one flock (Petersen et al, 2001).…”

Prevalence of thermophilic Campylobacter spp. in slaughtered pigs in the Czech Republic, 2001-2003

“…A similar study from the USA reported that 70-100% of pigs at slaughter (depending on the farm and the date samples were collected) were positive for Campylobacter (Harvey et al, 1999). Canadian authors Guevremont et al (2004) reported that …”