Investigation of zoonotically acquired Campylobacter jejuni enteritis with serotyping and restriction endonuclease DNA analysis

Characterization of Campylobacter jejuni, Campylobacter upsaliensis, and a novel Campylobacter sp. in a captive non-human primate zoological collection

BACKGROUND

The aim of this study was to longitudinally investigate the prevalence and characterization of Campylobacter spp. from non-human primates primate (NHP) with a history of endemic diarrhea housed at Como Park Zoo.

METHODS

Fecal samples from 33 symptom-free NHP belonging to eight different species were collected weekly for 9 weeks. Species-level characterization and phylogenetic analysis of isolates included biochemical testing and 16S rRNA sequencing.

RESULTS

Campylobacter spp. were isolated from the feces of 42% (14/33) of the primates. Three Campylobacter spp. (C upsaliensis, C jejuni, and novel Campylobacter sp.) were identified from three NHP species. A possible positive host Campylobacter species-specificity was observed. However, no statistical association was observed between the isolation of Campylobacter spp. and age and sex of the animal.

CONCLUSIONS

The study revealed the value of conducting repeated fecal sampling to establish the overall prevalence of Campylobacter in zoo-maintained NHP; it also importantly identifies a novel Campylobacter sp. isolated from white-faced saki monkeys.

Selected Zoonoses

Human risks of acquiring a zoonotic disease from animals used in biomedical research have declined over the last decade because higher quality research animals have defined microbiologic profiles. Even with diminished risks, the potential for exposure to infectious agents still exists, especially from larger species such as nonhuman primates, which may be obtained from the wild, and from livestock, dogs, ferrets, and cats, which are generally not raised in barrier facilities and are not subject to the intensive health monitoring performed routinely on laboratory rodents and rabbits. Additionally, when laboratory animals are used as models for infectious disease studies, exposure to microbial pathogens presents a threat to human health. Also, with the recognition of emerging diseases, some of which are zoonotic, constant vigilance and surveillance of laboratory animals for zoonotic diseases are still required.

Restriction fragment length polymorphism for the identification of Campylobacter jejuni-isolates

Companion animals ("pets") are occasionally carriers of organisms pathogenic for man. In the present, study fecal samples of clinically inapparent animals with direct contact to 204 patients, suffering from campylobacter enteritis, were investigated for C. jejuni or C. coli (CJC). CJC positive animals were seen in the environment of only five patients (= 2.4%). By comparison of biotypes and serotypes of thermostable and thermolabile antigens from human and animal isolates no clear epidemiological relationship could be deduced. Using chromosomal DNA of the strains, genetic identity of the isolates was studied for HaeIII-restriction fragment length polymorphism (RFLP), applying a biotinylated commercial CJ probe. The probe was found to be specific for most CJ strains and revealed a pattern of one to four bands. In contrast to biotyping no identity of patient strains and animal isolates was seen in three cases; one case with different biotypes had identical RFLP patterns; one patient CJ strain did not show any pattern with the CJ probe. Serotypes were identical for a larger number of animal strains but differed in HaeIII RFLP and vice versa. Comparing the results from the different technological approaches it seems impossible to give a clear statement on the epidemiology of campylobacter infections or carrier state by biotyping alone. It is concluded that DNA RFLP patterns are a useful additional tool, but for epidemiological analysis a set of different methods should be used.