Campylobacter

Species within the genus, Campylobacter, have emerged over the last three decades as significant clinical pathogens, particularly of human public health concern, where the majority of acute bacterial enteritis in the Western world is due to these organisms. Of particular concern are the species, C. jejuni and C. coli, which are responsible for most of these gastrointestinal-related infections. Although these organisms have already emerged as causative agents of zoonoses, several aspects of their epidemiology and pathophysiology are only beginning to emerge. Trends in increasing antibiotic resistance are beginning to emerge with oral antibiotics, which may be the drug of choice for when it is necessary to intervene chemotherapeutically. This review wishes to examine (i) emerging clinical aspects of the disease, such as Guillain Barre syndrome (GBS), (ii) the association between these organisms and poultry as a natural host, (iii) environmental aspects of Campylobacter epidemiology, (iv) the emergence of atypical campylobacters (v) emerging trends in antibiotic resistance, (vi) adoption of modern methods for the detection of campylobacters.     

Campylobacter infection and Campylobacter excretion in turkeys

Five turkey poults at an age of 27 days were infected with Campylobacter jejuni strain. Additional five poults were infected by contact. Turkeys infected by contact and artificially were necropsied 1 and 3 months later, respectively. The histological examination of the liver revealed degenerative changes in contact birds and a proliferation of the connective tissue and bile-ducts in two of the oral infected poults. Campylobacter spp. were excreted daily during the first two weeks and afterwards with interruptions of several days. The excretion lasted until the end of the experiment between day 86 and 98. The excretion period, which is prolonged compared with that of chickens may be of particular importance under aspects of epizootiology and food hygiene.     

Campylobacter jejuni and Campylobacter coli inoculation of neonatal calves

Three groups of neonatal calves were inoculated orally with pathogenic strains of Campylobacter jejuni or C coli. The calves developed a mild, self-limiting enteritis characterized by thick mucoid feces. Bacteremia and fecal shedding of Campylobacter were sporadic in all inoculated calves. Two groups of calves were killed 1 to 3 weeks after inoculation to study the pathogenesis of infection. Postmortem culture of tissues revealed C jejuni or C coli most frequently in the ileum, cecum, colon, and blood. Clinical or pathologic differences between C jejuni-inoculated and C coli-inoculated calves were minimal.     

禽类弯曲杆菌

弯曲杆菌及其同属菌群是脊椎动物和某些非脊椎动物口腔及肠道内的共生菌,这种特性导致控制家禽中弯曲杆菌污染问题复杂化。本文详细讨论了弯曲杆菌的系统发育,基因组学及其生理学,深入揭示了这些微生物是如何通过进化,进而占据肠道的有利环境,提出只有深刻了解它们的生理学,才能制定有效的控制方案。     

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.     

Higher resistance of Campylobacter coli compared to Campylobacter jejuni at chicken slaughterhouse

In order to compare the prevalence of Campylobacter coli and Campylobacter jejuni during the processing of broilers at slaughterhouse a total of 848 samples were analyzed during 2012 in southern Spain. Four hundred and seventy six samples were collected from cloaca, carcass surfaces and quartered carcasses. Moreover, 372 environmental swabs from equipment and scalding water were collected. Minimum inhibitory concentration (MIC) to ciprofloxacin, erythromycin, streptomycin, tetracycline and gentamicin was determined for isolates from chicken meat. The general prevalence of Campylobacter was 68.8% (40.2% of C. coli and 28.5% of C. jejuni). The relative prevalence of C. coli increased from loading dock area (41.5%) to packing area (64.6%). In contrast, the relative prevalence of C. jejuni decreased from 58.5% to 35.4%. These differences between species from initial to final area were significant (p = 0.02). The highest antimicrobial resistance for C. jejuni and C. coli was detected to tetracycline (100%) and ciprofloxacin (100%), respectively. Campylobacter coli showed an antimicrobial resistance significantly higher than C. jejuni to streptomycin (p = 0.002) and erythromycin (p < 0.0001).     

Serogroups of Campylobacter fetus and Campylobacter jejuni isolated in cases of ovine abortion

Of 38 aborted ovine fetuses from 23 sheep flocks 29 C. fetus subsp. fetus and 22 C. jejuni were isolated and examined biochemically and serologically for heat-stable antigens. Serologic examinations were carried out by passive haemagglutination test. In case of C. fetus subsp. fetus strains alkaline antigen extraction was used. Antisera to two serogroups of C. fetus and to Penner serotype reference strains 1 to 60 were produced in rabbits. Abortion was caused in 18 (78.3%) flocks by C. fetus subsp. fetus and in 5 (21.7%) flocks by C. jejuni. Six C. fetus subsp. fetus strains grew well at both 43 and 25 degrees C. With one exception all C. fetus subsp. fetus were resistant, whereas all 29 C. fetus subsp. venerealis strains were sensitive to 30 micrograms/ml cefoxitin and cefamandole. These two cephalosporins can be used to differentiate the two subspecies of C. fetus. Passive haemagglutination test using alkaline antigen extraction is a proper method for the examination of heat-stable antigens of both C. fetus subspecies. Out of 24 C. fetus subsp. fetus strains 13 belonged to serogroup A(01), and 11 to serogroup B(02). C. jejuni strains examined belonged to Penner serogroup 1 (6 strains), to serogroup 5 (4 strains) and to serogroup 8 (4 strains).     

Fecal shedding of Campylobacter jejuni and Campylobacter coli among feral pigs in Texas

The population and range of feral pigs in the United States are rapidly expanding, yet key knowledge gaps exist regarding their role in the ecology and transmission of foodborne pathogens. Our objectives were to estimate the prevalence of Campylobacter jejuni and Campylobacter coli shedding among feral pigs throughout Texas and to identify risk factors for positive status. Faecal samples were collected from feral pigs in Texas from February 2014 through May 2015, and target organisms were detected using PCR assays. The prevalence of C. jejuni shedding was 1.6% (6/370), and the prevalence of C. coli shedding was 3.5% (13/370). C. coli shedding was significantly more common (p = .008) among female pigs than among male pigs. Feral pigs may represent a source of human campylobacteriosis.