Combined Campylobacter jejuni and Campylobacter coli Rapid Testing and Molecular Epidemiology in Conventional Broiler Flocks

Abstract

Campylobacter spp. are important causes of bacterial zoonosis, most often transmitted by contaminated poultry meat. From an epidemiological and risk assessment perspective, further knowledge should be obtained on Campylobacter prevalence and genotype distribution in primary production. Consequently, 15 Austrian broiler flocks were surveyed in summer for their thermophilic Campylobacter spp. contamination status. Chicken droppings, dust and drinking water samples were collected from each flock at three separate sampling periods. Isolates were confirmed by PCR and subtyped. We also compared three alternative methods (culture-based enrichment in Bolton broth, culture-independent real-time PCR and a lateral-flow test) for their applicability in chicken droppings. Twelve flocks were found to be positive for thermophilic Campylobacter spp. during the entire sampling period. Seven flocks (46.6%) were contaminated with both, C. jejuni and C. coli, five flocks harboured solely one species. We observed to a majority flock-specific C. jejuni and C. coli genotypes, which dominated the respective flock. Flocks within a distance <2 km shared the same C. jejuni genotypes indicating a cross-contamination event via the environment or personnel vectors. Multilocus sequence typing (MLST) of C. jejuni revealed that the majority of isolates were assigned to globally distributed clonal complexes or had a strong link to the human interface (CC ST-446 and ST4373). The combination of techniques poses an advantage over risk assessment studies based on cultures alone, as, in the case of Campylobacter, occurrence of a high variety of genotypes might be present among a broiler flock. We suggest applying the lateral-flow test under field conditions to identify 'high-shedding' broiler flocks at the farm level. Consequently, poultry farmers and veterinarians could improve hygiene measurements and direct sanitation activities, especially during the thinning period. Ultimately, real-time PCR could be applied to quantify Campylobacter spp. directly from chicken droppings and avoid non-interpretable results achieved by culture-dependent methods.

Population structure and attribution of human clinical Campylobacter jejuni isolates from central Europe to livestock and environmental sources

“…Campylobacter jejuni, transmitted via undercooked poultry meat, chicken liver paté and contaminated raw milk, is a major cause of foodborne diarrhoeal illness, which affects humans worldwide (Kaakoush, Castaño‐Rodríguez, Mitchell, & Man, ; Lahti, Löfdahl, Ågren, Hansson, & Olsson Engvall, ). Despite domesticated animals, particularly poultry and cattle, being recognized as the main sources of infection (Levesque et al., ; Schallegger et al., ; Sheppard et al., ), the role of water and wildlife as sources and transmitting agents is not yet well understood (Cody et al., ; Hald et al., ; Skarp, Hänninen, & Rautelin, ). Environmental surface water is commonly contaminated with Campylobacter due to the sewage discharge, as well as domestic and wild animal faecal input (Marcheggiani et al., ; Rechenburg & Kistemann, ; Sales‐Ortells, Agostini, & Medema, ; Sales‐Ortells & Medema, ).…”

The Relationship between Human Campylobacteriosis and Broilers

“…2,8 From an epidemiological and risk assessment perspective, further knowledge should be obtained on Campylobacter prevalence and genotype distribution in primary production. 35 Effective quality assurance schemes, including Good Laboratory Practice (GLP), which includes continuous monitoring and improvement, are vital for cogent diagnostic laboratories. 2 In developed countries molecular methods, e.g.…”

“…37 Feed additives (pre and probiotics) have potential to reduce Campylobacter infection in flocks. 35 Probiotics, e.g. Lactobacillus salivarius SMXD5, may exhibit an anti-Campylobacter activity in vivo and partially prevent the impact of Campylobacter on the avian gut microbiota.…”