Prevalence of thermophilic campylobacter infections in humans, chickens and crows in Morogoro, Tanzania

Prevalence of thermophilic Campylobacter infections in humans, chickens and crows was determined in a cross-sectional study that was carried out in urban and rural areas of Morogoro region, Tanzania during the period of January 2003 to December 2004. A total of 632 human stool samples, 536 cloacal swabs from local and broiler chickens and 22 intestinal contents from crows were screened for presence of thermophilic campylobacters using Skirrow's protocol. Representative Campylobacter jejuni isolates from human and chicken samples were also analysed by polymerase chain reaction (PCR) as a definitive identification method. The overall prevalence of thermophilic campylobacters was 9.3% (95% CI: 7.2-11.9), 69.8% (95% CI: 65.7-73.6) and 72.7% (95% CI: 49.8-89.3) in humans, chickens and crows respectively. In humans, 59 thermophilic campylobacters were isolated of which 96.6% were C. jejuni and 3.4%Campylobacter coli. There was a significantly (P<0.001) higher prevalence in young individuals (16%) than in adults (7%). Of 341 isolates from chickens, 91.2% were C. jejuni and 8.8% were C. coli. A significantly (P<0.05) higher infection rate was observed in rural local chicken (76%) than in broilers (60%). In crows, of 16 isolates, 93.8% were C. jejuni and 6.2% were C. coli. Definitive identification of C. jejuni by PCR revealed positive results in 74.1% of 243 analysed isolates. Findings in this study indicate high prevalence of thermophilic campylobacters in humans, chickens and crows in Morogoro, and a higher infection rate of C. jejuni than that of C. coli in different animal species. Age of humans and location of chickens were identified as risk factors for thermophilic Campylobacter infections. Positive isolates to biochemical tests that indicated negative results on PCR indicates the additional value of PCR for definitive diagnosis of C. jejuni.     

Campylobacter in the dog: a clinical and experimental study

Faecal samples from 54 dogs with diarrhoea and 54 control dogs were cultured for Campylobacter, Salmonella and Yersinia species and controlled for enteric viruses. The campylobacter were identified as either C jejuni/coli or C upsaliensis. In the diarrhoeic group 16 dogs (29.6 per cent) were positive for campylobacter, 10 C upsaliensis and six C jejuni/coli. Concomitant infection with parvovirus was evident in six of the dogs with diarrhoea and campylobacter-positive faecal cultures. In the control group 13 dogs (24.1 per cent) were positive for campylobacter; three of the isolates were C upsaliensis and six C jejuni/coli. Four isolates could not be identified. The most prominent clinical findings in naturally occurring cases were an acute onset of vomiting (12 of 16), diarrhoea (16 of 16) which was often haemorrhagic (nine of 16) and a raised rectal temperature. Dogs were infected experimentally with both C jejuni (three dogs) and C upsaliensis (three dogs). The challenge strains could be identified in faecal samples from all the dogs, but clinical signs of diarrhoea were seen in only one dog infected with C jejuni. Soft faeces was passed by one dog infected with C upsaliensis. It is concluded that C jejuni/coli or C upsaliensis are either primary pathogens or, after predisposing factors such as virus infections, act as secondary pathogens. It also seems probable that Campylobacter species are present in the intestinal flora of the normal dog.     

Isolation of Campylobacter jejuni and Campylobacter coli from the gall bladder samples of sheep and identification by polymerase chain reaction

In this study, 100 gall bladder samples of sheep slaughtered at an abattoir in Elazi? province were examined for Campylobacter jejuni and Campylobacter coli by culture and polymerase chain reaction (PCR). Preston Campylobacter Agar supplemented with 7% horse blood and Preston Selective Supplement (Oxoid, Hampshire, UK) were used for isolation of the agents. Campylobacter spp. were isolated in 66 samples, and they were identified as 34% C. jejuni and 32% C. coli. A multiplex PCR based upon the use of ceuE gene-specific primers was applied on DNA samples extracted from C. jejuni and C. coli isolates. All C. jejuni and C. coli strains that were positive by culture were also detected to be positive by PCR. This study shows that PCR can be used an alternative, rapid and sensitive test for the identification of C. jejuni and C. coli which threaten human and animal health.     

The occurrence and characterization of Campylobacter spp. in silver gulls (Larus argentatus), three-toed gulls (Rissa tridactyla) and house sparrows (Passer domesticus)

Altogether 16 Campylobacter (C.) isolates could be recovered from 65 Herring gulls: 5 x C. laridis, 2 x C. jejuni biovar 1, 4 x C. jejuni biovar 2 and 5 x C. coli. Campylobacter spp. were isolated from 15 out of 51 samples from Kittiwakes: 2 x C. jejuni biovar 1 and 13 x C. laridis. All C. coli isolates grew on agar containing 1.5% NaCl. Two Campylobacter isolates from 50 House sparrows differed from all other isolates by a distinct beta-hemolysis and other phenotypic characteristics and could not be associated with a certain Campylobacter species. Epidemiological aspects and the possible role of the examined birds as a source of infection for man and domestic animals are discussed.     

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

The occurrence and species distribution of thermophilic Campylobacter was investigated in organic outdoor pigs. An increased exposure of outdoor pigs to C. jejuni from the environment may cause a shift from a normal dominance of C. coli to more C. jejuni, which may imply a concern of reduced food safety. Bacteriological methods for determination of Campylobacter excretion level were combined with colony-blot hybridization and real-time PCR for specific detection of C. jejuni in pigs. Campylobacter was isolated from pigs (n=47), paddock environment (n=126) and wildlife (n=44), identified to species by real-time PCR and sub-typed by serotyping (Penner) and pulse-field gel electrophoresis (PFGE) genotyping. All pigs excreted Campylobacter (10(3)-10(7) CFU g(-1) faeces) from the age of 8-13-weeks old. C. jejuni was found in 29% of pigs in three consecutive trials and always in minority to C. coli (0.3-46%). C. jejuni and C. coli were isolated from 10% and 29% of the environmental samples, respectively, while crow-birds and rats harboured C. jejuni. Individual pigs hosted several strains (up to nine serotypes). The paddock environment was contaminated with C. coli serotypes similar to pig isolates, while most of the C. jejuni serotypes differed. C. jejuni isolates of different origin comprised few similar serotypes, just one identical genotype was common between pigs, environment and birds. In conclusion, the occurrence of C. jejuni varied considerably between the three groups of outdoor pigs. Furthermore, transfer of C. jejuni to the outdoor pigs from the nearby environment was not predominant according to the subtype dissimilarities of the obtained isolates.     

Fla-DGGE analysis of Campylobacter jejuni and Campylobacter coli in cecal samples of broilers without cultivation

In a commercial broiler flock during rearing multiple genotypes of Campylobacter jejuni may be present as well as in gastrointestinal tracts of individual birds. The aim of this study was to optimize and apply a denaturing gradient gel electrophoresis assay of the flagellin gene (fla-DGGE) for analysis of C. jejuni and Campylobacter coli in cecal samples of broilers without prior cultivation. One C. coli and 21 C. jejuni strains isolated from broiler flocks, of which 14 typed as unique by restriction fragment length polymorphism of flaA and two undefined strains, were clustered into 9 groups when applying fla-DGGE. Spiking of cecal samples revealed that fla-DGGE is able to detect at least 4.55-5.96logCFUCampylobacter/mlcecal material. The presence of 3 strains spiked in cecal material was demonstrated by fla-DGGE as the corresponding bands were visible on the DGGE gel. Naturally contaminated cecal samples were shown to contain different types of C. jejuni and C. coli. Fla-DGGE has some potential as a cultivation-independent fast primary subtyping method for C. jejuni and C. coli in cecal samples of broilers.     

A cytolethal distending toxin gene-based multiplex PCR assay for detection of Campylobacter spp. in stool specimens and comparison with culture method

In this study, we evaluated the applicability of cytolethal distending toxin (cdt) gene-based species-specific multiplex PCR for the direct detection and identification of Campylobacter jejuni, C. coli and C. fetus from stool specimens of patients with gastroenteritis in comparison to culture methods. A total of 711 stool specimens were examined for the isolation or detection of campylobacters by using Skirrow's selective agar culture plates, a filtration method and the multiplex PCR assay. Forty-one and 36 C. jejuni strains were isolated by culture and filtration methods, respectively. In addition, 2 and 3 C. coli strains were isolated by Skirrow and the filtration methods, respectively. However, when the multiplex PCR was employed, the cdtB genes of C. jejuni and C. coli were detected in 45 and 4 stool samples, respectively, and 9 C. jejuni PCR-positive samples by multiplex PCR were negative by culture method. Sequence analysis of the PCR products obtained from 8 stool specimens from which campylobacters were not isolated by culture method but the sequences exactly matched with that of the cdtB gene of C. jejuni strain 81-176. None of the remaining stool samples which were culture negative for campylobacters produced any amplicon. Stool samples were defined as Campylobacter-positive if detected by any method. The sensitivity of the multiplex PCR was 83%, which was higher than Skirrow (74%) and filtration method (66%). These data indicate that cdtB gene-based multiplex PCR is a rapid and more sensitive method to identify the most important species of Campylobacter for human diseases. (248).     

Incidence of zoonoses in petting zoos and evaluation of hygiene measures to prevent the transmission to humans

In summer 2003, a study was performed in thirty Swiss petting zoos with the objective to determine the prevalence of zoonotic agents, and to describe hygiene measures implemented to reduce the risk of human infection. Fecal samples from different animal species were collected from the floor of pens to determine the prevalence of Salmonella spp., Campylobacter spp., verocytotoxin producing E. coli/ VTEC and Francisella tularensis. A questionnaire on hygiene measures, number of animals per species, housing system, care procedures and feeding was administered to every petting zoo to estimate exposure of visitors to zoonotic microorganisms. In total, 423 fecal samples were examined. Of these samples, 41 were positive for Campylobacter spp., which were mainly isolates from pigs and poultry (35% positive samples from each species). In pigs, 50% of the positive samples (6 samples) were typed as C. jejuni. The others were typed as C. coli (3) and C lan' (3), respectively. Five poultry isolates were typed as C. jejuni, and two as C. coli. Two samples were positive for Salmonella spp. Salmonella typhimurium was isolated from a goat, the other isolate could not be identified by serotyping. Neither Francisella tularensis nor verocytotoxin producing E. coli/ VTEC were found. The low prevalence of zoonotic microorganisms in Swiss petting zoos could be attributed to the cleanness of enclosures and animals, low stocking rates and good animal care. However, there is room for improvement concerning visitors' information on hygiene and hand washing. Furthermore, a strict separation between picnic - areas and animals should be enforced.     

Prevalence of Campylobacter spp isolated from the intestinal tract of pigs raised in an integrated swine production system

OBJECTIVE: To enumerate the prevalence of Campylobacter isolates in the intestinal tract of market-weight swine raised in an integrated swine operation in Texas. SAMPLE POPULATION: Samples of cecal contents were collected from 595 pigs (mean body weight, 110 kg [242 lb]) at time of slaughter. Pigs were off-spring of Yorkshire-Landrace sows and Duroc or Hampshire boars. Pigs originated from 4 farrow-to-finish farms. PROCEDURE: During a 9-month period, visits were made to a slaughter plant to remove cecal contents from market-weight hogs. Samples were obtained from 50 pigs/visit from designated farms so that samples were obtained 3 times from pigs of each of 4 farms. Isolation of Campylobacter spp was accomplished by use of enrichment broth and restrictive media, using microaerophilic conditions. RESULTS: Campylobacter spp were isolated from 70 to 100% of the pigs, depending on the farm and the date the samples were collected. Campylobacter coli was isolated from 20 to 100% (mean, 60%) of samples, and C jejuni was isolated from 0 to 76% (mean, 31%) of samples. Campylobacter lari was isolated from 2 pigs. Concentrations of C coli or C jejuni ranged from 10(3) to 10(7) colony-forming units/g of cecal content. CONCLUSIONS AND CLINICAL RELEVANCE: Campylobacter coli generally is accepted as a common inhabitant of the intestinal tract of swine. However, analysis of results of this study suggests that a relatively high prevalence of C jejuni may be found in pigs raised on specific farms.     

Campylobacter jejuni infection in the ferret: an animal model of human campylobacteriosis

Campylobacter infection in weanling ferrets (Mustela putorius furo) was studied as an animal model for enteric campylobacteriosis in persons. The screening of fecal cultures on selective campylobacter media showed that Campylobacter jejuni/coli was not present in the normal enteric flora. Intragastric feeding of a mixture of cat feed and 2.5 X 10(8) C jejuni isolated from ferrets with naturally occurring proliferative colitis was accomplished. All ferrets (n = 8) became infected on 3 days after they were inoculated, and at 5 to 7 days, they had bile-tinged, liquid feces with excessive mucus and blood. Ferrets gradually recovered from the diarrhea, and feces were normal 10 to 14 days after inoculation was done. Feces contained C jejuni at 14, 23, 28, 39, 46, 60, 91, 101, 109 and 144 days. In the second experiment, weanling ferrets initially were treated with 10% sodium bicarbonate, and 1 X 10(10) C jejuni organisms were administered in the cat feed. Diarrhea with fecal leukocytes and occult blood with occasional mucus appeared in almost all of the 21 ferrets from days 4 through 7. Campylobacter jejuni was isolated from the blood of 11 ferrets between 3 hours and 14 days after they were inoculated. Campylobacter jejuni bactericidal antibodies were present in serum samples at 14 days, with titers of 1:16 to 1:32. Intestinal lesions including cellular infiltration with mononuclear and polymorphonuclear leukocytes were in the lamina propria of the pyloric mucosa and small intestine of infected and control ferrets. The colon of 3 infected ferrets had small focal infiltrates of neutrophils on the lamina propria; one ferret had perivascular cuffing.(ABSTRACT TRUNCATED AT 250 WORDS)     

Heterogeneity of Campylobacter jejuni and Campylobacter coli strains from healthy sheep

The objectives of this study were to identify, at species level, thermophilic campylobacters isolated from clinically healthy sheep by a multiplex polymerase chain reaction (mPCR). The heterogeneity among Campylobacter jejuni and C. coli isolates was also investigated using a restriction fragment length polymorphism (RFLP) analysis of the flagellin (flaA) gene. Samples of intestinal contents, gall bladders and faeces were collected from 610 healthy sheep. While gall bladder samples were plated directly onto Preston agar, an enrichment stage was applied for intestinal and faecal samples. Of the 610 samples, 302 (49.5%) were positive for Campylobacter spp. Using a mPCR assay for species identification, 103 (34.1%) were positive with C. jejuni-specific primers, while 100 (33.1%) were positive with C. coli-specific primers. Additionally, 16 (11.9%) of the intestinal content samples were positive for both species by mPCR. All the isolates identified as C. jejuni and C. coli were successfully subtyped by flaA typing. Of 203 isolates tested, 48 different flaA types were found. Twenty-six flaA types were identified among C. jejuni isolates and the remaining 22 from C. coli isolates.     

Campylobacter spp. and their antimicrobial resistance patterns in poultry: an epidemiological survey study in Turkey

The current study aimed at determining the prevalence and the antimicrobial resistance profiles of thermophilic Campylobacter spp. infecting broiler chickens. A total of 240 caecal samples from six slaughterhouses were examined for the presence of Campylobacter spp. C. jejuni was detected in 40.4% (97/240) of the samples and C. coli in 12.1% (29/240). The agar disc diffusion method and the E-test were used for testing the antimicrobial susceptibility of C. jejuni and C. coli isolates. C. jejuni isolates were most resistant to nalidixic acid (79.4%) followed by tetracycline (76.3%), ciprofloxacin (74.2%) and enrofloxacin (15.5%). Among the C. coli isolates, the frequency of resistance to nalidixic acid and ciprofloxacin was the same at 65.5%. The predominant profiles of multidrug resistance to three or more antimicrobials in C. jejuni and C. coli were determined as tetracycline/nalidixic acid/ciprofloxacin resistance (48.5%) and tetracycline/nalidixic acid/ciprofloxacin/enrofloxacin resistance (51.7%), respectively. To prevent the transmission of antimicrobial-resistant bacteria of animal origin to humans, it should be noted that high proportions of multidrug resistance were found in both species.     

Campylobacter infections in calves, piglets, lambs and kids in Trinidad.

Faeces or rectal swabs from 689 diarrhoeic and non-diarrhoeic animals were cultured for thermophilic campylobacters and their antibiograms were determined. Three hundred and fifteen (45.7%) samples were positive for Campylobacter. Piglets had the highest prevalence, 79.3% (233/294) and lambs, the lowest with 17.9% (15/84) being positive. The difference was statistically significant (P < or = 0.01; chi 2). In calves, 20.5% (60/293) and in kids 38.9% (7/18) were positive for campylobacters. The prevalence of infection was not significantly (P > or = 0.05; chi 2) different between diarrhoeic (46.1%) and non-diarrhoeic (45.1%) animals nor between male (47.5%) and female (43.8%). The frequency of isolation of campylobacters harvested from semi-intensively managed animals (75.4%) was, however, significantly higher (P < or = 0.001; chi 2) than from intensively or extensively managed animals. Overall, C. coli strains (32.8%) were more frequently isolated than C. jejuni strains (12.9%) and the difference was significant (P < or = 0.001; chi 2). Biotype I accounted for 67.3% (152/226) of C. coli and 64.0% (57/89) of C. jejuni strains isolated. A total of 245 (77.8%) strains of Campylobacter exhibited resistance to one or more antibiotics and was highest to streptomycin (76.5%), kanamycin (28.6%) and neomycin (26.7%). It was concluded that Campylobacter infections were widespread in livestock in Trinidad, particularly C. coli in piglets.     

Campylobacter jejuni, Campylobacter coli, and cytolethal distending toxin genes in laying hens

As no data are available on the prevalence of cytolethal distending toxin (cdt) genes carried by Campylobacter spp. in laying hens, this study was conducted with the aim to evaluate the prevalence of both Campylobacter spp. and cdt genes in 1680 laying hens from four different farms. The samples were analyzed by culture methods and by polymerase chain reaction. Campylobacter spp. were isolated from 1097/1680 cloacal swabs. Among the isolates, 913 were identified as Campylobacter jejuni whereas 345 were identified as Campylobacter coli. All isolates carried cdt genes. The results presented here confirm the very common occurrence of C. jejuni and C. coli in laying hens and underline that the cdt genes may also be frequently present in both C. jejuni and C. coli isolates from laying hens.     

Prevalence of thermophilic campylobacters in crows (Corvus levaillantii, Corvus corone) and serogroups of the isolates

A total of 500 fecal droppings of crows collected from a seashore of an ocean bay and from a cemetery on a hill surrounded by a forest were examined for thermophilic campylobacters, and the Skirrow's biovars and Penner's serogroups of the isolates were determined. The organisms were isolated from 169 (62.6%) of 270 seashore crow samples and 106 (46.1%) of 230 cemetery crow samples. During the investigation period from May 1986 to April 1987, the monthly isolation rate of thermophilic campylobacters in the seashore crow varied from 32.0 to 85.0%. C. jejuni, C. coli, and C. laridis were isolated from 150, 21 and 14 samples, respectively. In case of the cemetery crow, the monthly isolation rate varied from 20.0 to 75.0%, and C. jejuni, C. coli, and C. laridis were detected from 80, 12 and 16 samples, respectively. Among 192 strains of C. jejuni selected from 98 seashore and 57 cemetery crow samples, 106 (93.0%) of 114 seashore crow strains and 69 (88.5%) of 78 cemetery crow strains were identified as Skirrow's biovar I. Of 192 strains of C. jejuni serogrouped, 169 strains were classified into 20 serogroups. The Penner's serogroup 2, one of common serogroups among poultry and human isolates in Japan, was the most predominant in crow strains.     

Campylobacter as the cause of diarrhea in calves]

The modified Preston medium allows the isolation of C. jejuni, C. coli and C. fetus subsp. fetus from intestinal samples of calves at an incubation temperature of 37 degrees C. In the first series of investigation, Campylobacter excretion in calves (n = 7) was followed up to the age of 4 months. In the first 4 days of life, these bacteria could not be detected in any of the animals. Thereafter first C. coli we found in all calves. In 4 animals, only strains of this species were isolated during the whole investigation period. In 3 animals C. fetus subsp. fetus could be detected repeatedly, however C. coli and sometimes C. jejuni were found, too. In the second series of investigation, isolation of Campylobacter from different parts of the gastrointestinal tract or organs was successful in 19 out of 25 diarrhoeal, moribund calves. 16 out of 19 positive animals harboured large amounts of these gramnegative bacteria in the distal jejunum and ileum. In 10 animals out of these 16, the germ colonized also the proximal jejunum and abomasum. From 6 calves, C. fetus subsp. fetus was isolated, and C. jejuni from 7 calves. C. coli was relatively rare. From the lymph nodes of the proximal and distal jejunum, Campylobacter (exclusively C. jejuni) were isolated from 5 animals. Due to the Campylobacter presence in the small intestine of diarrhoeal calves, a contribution of this bacteria within the pathogenesis of calf diarrhoea is possible. Final evaluation of their pathogenesis importance is only positive by means of virulence tests.     

Campylobacter spp., Salmonella spp., verocytotoxic Escherichia coli, and antibiotic resistance in indicator organisms in wild cervids

Faecal samples were collected, as part of the National Health Surveillance Program for Cervids (HOP) in Norway, from wild red deer, roe deer, moose and reindeer during ordinary hunting seasons from 2001 to 2003. Samples from a total of 618 animals were examined for verocytotoxic E. coli (VTEC); 611 animals for Salmonella and 324 animals for Campylobacter. A total of 50 samples were cultivated from each cervid species in order to isolate the indicator bacterial species E. coli and Enterococcus faecalis / E. faecium for antibiotic resistance pattern studies. Salmonella and the potentially human pathogenic verocytotoxic E. coli were not isolated, while Campylobacter jejuni jejuni was found in one roe deer sample only. Antibiotic resistance was found in 13 (7.3%) of the 179 E. coli isolates tested, eight of these being resistant against one type of antibiotic only. The proportion of resistant E. coli isolates was higher in wild reindeer (24%) than in the other cervids (2.2%). E. faecalis or E. faecium were isolated from 19 of the samples, none of these being reindeer. All the strains isolated were resistant against one (84%) or more (16%) antibiotics. A total of 14 E. faecalis-strains were resistant to virginiamycin only. The results indicate that the cervid species studied do not constitute an important infectious reservoir for either the human pathogens or the antibiotic resistant microorganisms included in the study.     

Occurrence and significance of different Campylobacter types in domestic animals in Hungary

Experiences, including results of original experimental work on Campylobacter fetus, C. jejuni and C. coli induced diseases of cattle, sheep, dogs, rabbits poultry and men in Hungary are reviewed. Out of 31 cases of abortion in cows 29 (93.5%) were causes by C. fetus subsp. venerealis and only one case each (3.2%) by C. fetus subsp. fetus and C. jejuni, respectively. Out of the 29 strains of C. fetus subsp. venerealis, 26 belonged to serogroup 01 (A) and only 3 to serogroup 02 (B). Campylobacter abortions in sheep flocks were caused in 18 cases (78.3%) by C. fetus subsp. fetus and in 5 cases (21.7%) by C. jejuni. The latter strains belonged to Penner's serogroup 1 (6 strains), 5 (4 strains) and 8 (5 strains), respectively. In scouring dogs 12.7% of the cases were caused by C. jejuni. The same pathogen caused diarrhoea also in young rabbits. Isolated strains belonged to serogroup 2. In cases of Campylobacter hepatitis of laying hens, egg production has been reduced by 8 to 15% for 2 to 3 weeks. Row poultry meat represents often the source of infection for men. The 32 strains of C. jejuni isolated from faecal samples of men affected with diarrhoea belonged to 12 serogroups.     

Phenotypes and genotypes of campylobacter strains isolated after cleaning and disinfection in poultry slaughterhouses

Campylobacter is responsible for human bacterial enteritis and poultry meat is recognised as a primary source of infection. In slaughterhouses, cleaning and disinfection procedures are performed daily, and it has been suggested that disinfectant molecules might select for antibiotic resistant strains if shared targets or combined resistance mechanisms were involved. The aim of the study was to investigate if cleaning and disinfection procedures in poultry slaughterhouses select for antibiotic resistance in Campylobacter jejuni and C. coli and to determine the genotypes of isolates collected after cleaning and disinfection. Nine sampling visits were made to four French slaughterhouses. Samples were collected from transport crates and equipment surfaces, before and after cleaning and disinfection. Minimal inhibitory concentrations of the recovered C. jejuni and C. coli isolates to six antibiotics and two disinfectants were measured. The C. jejuni isolates collected from equipment surfaces after cleaning and disinfection were subjected to PCR-RFLP typing. Twenty-five C. jejuni isolates and 1 C. coli were recovered from equipment surfaces after cleaning and disinfection during five visits to three different slaughterhouses. Those isolates did not show an increased resistance to the tested antibiotics compared to isolates collected before cleaning and disinfection. Only one or two genotypes were recovered after cleaning and disinfection during single visits to each slaughterhouse. This observation suggests that such genotypes may be particularly adapted to survive cleaning and disinfection stress. Understanding the survival mechanisms of Campylobacter should facilitate the implementation of better-targeted strategies and reduce the public health burden associated with Campylobacter infection.     

Experimental infection of specific pathogen-free pigs with Campylobacter: excretion in faeces and transmission to non-inoculated pigs

Campylobacter species are leading agents of human bacterial gastroenteritis and consumption of food of animal origin is a major source of infection. Although pigs are known to frequently exhibit high counts of Campylobacter in their faeces, more information is needed about the dynamics of this excretion. An experimental trial was conducted to evaluate the faecal excretion of Campylobacter by 7-week-old specific pathogen-free piglets inoculated per os with three Campylobacter strains (one C. coli isolated from a pig, one C. coli and one C. jejuni from chickens) alone or simultaneously (5x10(7)CFU/strain). Non-inoculated pigs were housed in adjacent pens. Pigs were monitored for 80 days for clinical signs and by bacteriological analysis of faeces. Pigs inoculated with porcine C. coli or with a mix of the three strains excreted from 10(3) to 10(6)CFU/g of faeces with a slight decrease at the end of the trial. Animals inoculated with poultry C. coli or C. jejuni strain excreted a lower quantity and some of them stopped excreting. At the end of the trial, only C. coli was detected in the faeces of pigs inoculated simultaneously with the three bacteria. Moreover, the transmission of Campylobacter was noticed between pens for the two C. coli strains and all the neighbouring animals became shedders with a level of excretion similar to the inoculated pigs. Intermittence in the Campylobacter excretion was also observed. Finally, our study highlighted a host preference of Campylobacter, namely C. coli seems to have a higher colonization potential for pigs than C. jejuni.