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1.
A 9-year-old female mixed-breed dog presented with ascending flaccid tetraparesis, and a 5-year-old castrated male Poodle dog presented with ventroflexion of neck, dysphonia, and hindlimb weakness, which progressed to acute ascending tetraparesis. Both dogs were fed raw poultry for over 9 and 5 years, respectively. Blood examination and other test results were normal or unrelated to the present case. Fecal polymerase chain reaction analysis in the Poodle dog was positive for Clostridium perfringens and Campylobacter jejuni. Tetraparesis improved with supportive care in both dogs. Human IV immunoglobulin was only administered to the Poodle dog, which showed a shorter recovery (12 days compared to 34 days in the mixed-breed dog). Both dogs returned to normal conditions eventually.  相似文献   

2.
To investigate the possible role of cpb2-positive type A Clostridium perfringens in neonatal diarrheal illness in pigs, the jejunum and colon of matched normal and diarrheic piglets from 10 farms with a history of neonatal diarrhea were examined grossly and by histopathology, and tested for C. perfringens, for C. perfringens beta2 (CPB2) toxin, as well as for Clostridium difficile toxins, Salmonella, enterotoxigenic Escherichia coli, rotavirus, transmissible gastroenteritis (TGE) virus, and coccidia. Clostridium perfringens isolates were tested using a multiplex real-time polymerase chain reaction (PCR) to determine the presence of cpa, consensus and atypical cpb2, and other virulence-associated genes. The numbers of C. perfringens in the intestinal contents were lower in diarrheic piglets (log10 5.4 CFU/g) compared with normal piglets (log10 6.5 CFU/g) (P < 0.05). The consensus cpb2 was present in 93% of isolates in each group, but atypical cpb2 was less common (56% healthy, 32% diarrheic piglets isolates, respectively, P < 0.05). The presence of CPB2 toxin in the intestinal contents of normal and diarrheic piglets did not differ significantly. Clostridium difficile toxins and rotavirus were each detected in 7 of the 21 (33%) diarrheic piglets. Rotavirus, C. difficile toxins, Salmonella, or enterotoxigenic E. coli were concurrently recovered in different combinations in 4 diarrheic piglets. The cause of diarrhea in 8 of the 21 (38%) piglets on 6 farms remained unknown. The etiological diagnosis of diarrhea could not be determined in any of the piglets on 2 of the farms. This study demonstrated that the number of cpb2-positive type A C. perfringens in the intestinal contents was not a useful approach for making a diagnosis of type A C. perfringens enteritis in piglets. Further work is required to confirm whether cpb2-carrying type A C. perfringens have a pathogenic role in enteric infection in neonatal swine.  相似文献   

3.
Intestinal contents of suckling (n?=?45) and newly weaned (n?=?45) piglets, suffering from diarrhea in the province of Villa Clara in Cuba, were tested for viral, bacterial, and parasitic enteropathogens from May to June 2008. At least one enteropathogen was identified in 53.3 % of piglets and enterotoxigenic Escherichia coli (ETEC; 25.6 %) was the major pathogen; mostly STa+/STb+ or F4+/STa+/STb+ ETEC were isolated. The overall occurrence of the rest of pathogens was 10 % for transmissible gastroenteritis virus (TGEV) and Cryptosporidium parvum, 6.7 % for rotavirus A and Isospora suis, 5.6 % for α-toxigenic Clostridium perfringens, 3.3 % for verotoxigenic E. coli (VTEC), and 2.2 % for Salmonella enterica subspecies enterica serovar Newport. TGEV and α-toxigenic C. perfringens were only identified in suckling piglets, while Salmonella Newport and VTEC were only detected in weaned pigs. Porcine epidemic diarrhea virus (PEDV), β-toxigenic C. perfringens, Eimeria spp., and helminths were not identified. Eight kinds of mixed infections were detected in 25 % of enteropathogen positive piglets. ETEC was present in 10 of 12 mixed infections, and TGEV infections were never combined. This survey demonstrates that several enteropathogens are circulating in piggeries located in the province of Villa Clara in Cuba, and that is necessary to improve surveillance, prevention, and control of enteric infections in order to increase production efficiency.  相似文献   

4.
An eleven-year-old Chinese Crested Powder Puff dog presented with polydipsia/polyuria, inappetence, diarrhea and vomiting underwent an ultrasound-guided percutaneous liver biopsy. Two days post-biopsy the clinical condition of the dog acutely deteriorated with fever, dyspnea, ataxia and subcutaneous emphysema. Radiographs and ultrasound showed focal severe hepatic emphysema in the region of the previous liver biopsy. Post-mortem examination revealed chronic hepatitis with dissecting fibrosis, acute hepatitis with hemorrhage and in the hindlimb musculature extensive hemorrhage and necrosis. Pure cultures of the gas producing bacteria Clostridium perfringens were isolated in samples from the hind limb musculature. We propose that the hepatic emphysema in the region of the biopsy site was a result of a clostridial infection.  相似文献   

5.
Clostridium perfringens is an important zoonotic pathogen. This study was designed to explore the prevalence and toxin types of C. perfringens in retail beef collected from Beijing, China. Among 221 beef samples collected, 53 samples were positive for C. perfringens, resulting in the average prevalence as 23.98%. By toxin gene-based typing, the most C. perfringens strains belong to type A (96.23%, 51/53), only 2 strains were identified as type D. By a multi-locus sequence typing (MLST)-based analysis, a total of 36 sequence types (STs) were detected, and the most STs (n=30) represented just a single strain. These finding suggested that the prevalence of C. perfringens in retail beef in Beijing was considerably high and these bacteria displayed extreme diversity in genetics.  相似文献   

6.
The virulence of Clostridium perfringens, a bacterium causing enteritis and enterotoxaemia in domestic and wild animals and humans, results largely from its ability to produce toxins. In 1997, an unknown toxin of C. perfringens, the β2-toxin, and its encoding gene cpb2 were described. Since that time numerous studies have been published dealing with a possible association of cpb2-harbouring strains of C. perfringens and the occurrence of enteric disease in domestic and wild animals and humans. This article offers an overview of the current literature on the spread and pathological significance of cpb2-harbouring C. perfringens. Unambiguous conclusions on the prevalence of cpb2 and the contribution of β2-toxin to the disease cannot be drawn from existing studies but in some animal species a strong correlation between the presence of cpb2-harbouring C. perfringens, the β2-toxin and enteric disease has been reported.  相似文献   

7.
Necrotic enteritis in broiler chickens is associated with netB positive Clostridium perfringens type A strains. It is known that C. perfringens strains isolated from outbreaks of necrotic enteritis are more capable of secreting factors inhibiting growth of other C. perfringens strains than strains isolated from the gut of healthy chickens. This characteristic could lead to extensive and selective presence of a strain that contains the genetic make-up enabling to secrete toxins that cause gut lesions. This report describes the discovery, purification, characterization and recombinant expression of a novel bacteriocin, referred to as perfrin, produced by a necrotic enteritis-associated netB-positive C. perfringens strain. Perfrin is a 11.5 kDa C-terminal fragment of a 22.9 kDa protein and showed no sequence homology to any currently known bacteriocin. The 11.5 kDa fragment can be cloned into Escherichia coli, and expression yielded an active peptide. PCR detection of the gene showed its presence in 10 netB-positive C. perfringens strains of broiler origin, and not in other C. perfringens strains tested (isolated from broilers, cattle, sheep, pigs, and humans). Perfrin and NetB are not located on the same genetic element since NetB is plasmid-encoded and perfrin is not. The bacteriocin has bactericidal activity over a wide pH-range but is thermolabile and sensitive to proteolytic digestion (trypsin, proteinase K). C. perfringens bacteriocins, such as perfrin, can be considered as an additional factor involved in the pathogenesis of necrotic enteritis in broilers.  相似文献   

8.
Clostridium perfringens is one of the major causes of intestinal disease in humans and animals. Its pathogenicity is contributed to by the production of a variety of toxins. In addition, predisposing environmental factors are important for the induction of C. perfringens-associated enteritis as shown by infection models. Environmental contamination, gastric and intestinal pH, intestinal microflora, nutrition, concurrent infections, and medical interventions may influence the intestinal colonization, growth, and toxin production by C. perfringens. Prevention of C. perfringens-associated enteritis may be mediated by the use of feed additives like probiotics, prebiotics, organic acids, essential oils, bacteriophages, lysozymes, bacteriocins, and antimicrobial peptides. Here we summarize and discuss published data on the influence of different environmental predisposing factors and preventive measures. Further research should focus on feed composition and feed additives in order to prevent C. perfringens-associated enteritis.  相似文献   

9.
Up to 60% of cases of equine colitis have no known cause. To improve understanding of the causes of acute colitis in horses, we hypothesized that Clostridium perfringens producing enterotoxin (CPE) and/or beta2 toxin (CPB2) are common and important causes of severe colitis in horses and/or that C. perfringens producing an as-yet-undescribed cytotoxin may also cause colitis in horses. Fecal samples from 55 horses (43 adults, 12 foals) with clinical evidence of colitis were evaluated by culture for the presence of Clostridium difficile, C. perfringens, and Salmonella. Feces were also examined by enzyme-linked immunosorbent assay (ELISA) for C. difficile A/B toxins and C. perfringens alpha toxin (CPA), beta2 toxin (CPB2), and enterotoxin (CPE). Five C. perfringens isolates per sample were genotyped for the following genes: cpa, cpb, cpb2 consensus, cpb2 atypical, cpe (enterotoxin), etx (epsilon toxin), itx (iota toxin), netB (necrotic enteritis toxin B), and tpeL (large C. perfringens cytotoxin). The supernatants of these isolates were also evaluated for toxicity for an equine cell line. All fecal samples were negative for Salmonella. Clostridium perfringens and C. difficile were isolated from 40% and 5.4% of samples, respectively. All fecal samples were negative for CPE. Clostridium perfringens CPA and CPB2 toxins were detected in 14.5% and 7.2% of fecal samples, respectively, all of which were culture-positive for C. perfringens. No isolates were cpe, etx, netB, or tpeL gene-positive. Atypical cpb2 and consensus cpb2 genes were identified in 15 (13.6%) and 4 (3.6%) of 110 isolates, respectively. All equine C. perfringens isolates showed far milder cytotoxicity effects than a CPB-producing positive control, although cpb2-positive isolates were slightly but significantly more cytotoxic than negative isolates. Based on this studied population, we were unable to confirm our hypothesis that CPE and CPB2-producing C. perfringens are common in horses with colitis in Ontario and we failed to identify cytotoxic activity in vitro in the type A isolates recovered.  相似文献   

10.
The present study aimed to isolate and genotype C. perfringens from healthy and diarrheic dromedary camels, pastures and herders; and to evaluate and compare antimicrobial susceptibility of the isolates. A total of 262 (56.3%) C. perfringens isolates were recovered from 465 samples of healthy and diarrheic dromedary camels, pastures and herders. C. perfringens type A (75.2%), type B (4.2%), type C (13.7%) and type D (6.9%) were detected. C. perfringens type A with only cpa+ gene was found in 191 (72.9%) isolates and with cpa+ associated cpb2+ was found only in 6 (2.3%) isolates. None of the isolates were positive for cpe and iap genes.The highest antimicrobial resistance (82.8%) was observed to ceftiofur with MIC50 and MIC90 values of <64 and ≥256 μg/mL, respectively, followed by penicillin G (72.9%) and erythromycin (61.5%). The lowest resistance (1.9%) was observed for doxycycline with MIC50 and MIC90 values of <1 and 4 μg/mL, respectively, followed by florfenicol (5.3%) and clindamycin (12.2%). In conclusion, C. perfringens type A with cpa+ gene was the most prevalent toxin type isolated in this study. The majority of the isolates were resistant to at least one of the ten antimicrobials tested. Antimicrobial resistance patterns of C. perfringens isolates provide further evidence on the emergence of multiple-drug resistant C. perfringens. Therefore, the dissemination of surveillance programs to monitor and control C. perfringens in dromedary camels is required.  相似文献   

11.
A four day old Appaloosa foal in Alberta died from hemorrhagic enterotoxemia. Beta-toxin of Clostridium perfringens was demonstrated in the intestinal contents of the foal and a pure culture of C. perfringens type C was grown from the small intestine. Histological examination showed hemorrhage and extensive necrosis of the small intestinal mucosa. Areas of necrotic tissue were surrounded by massive numbers of clostridia-like rods. There was also a moderate degree of thyroid hyperplasia. This is believed to be the first published report of hemorrhagic enterotoxemia associated with C. perfringens type C in the horse in Canada.  相似文献   

12.
Clostridium-related poultry diseases such as necrotic enteritis (NE) and gangrenous dermatitis (GD) cause substantial economic losses on a global scale. Two antigenic Clostridium perfringens proteins, elongation factor Tu (EF-Tu) and pyruvate:ferredoxin oxidoreductase (PFO), were identified by reaction with immune sera from commercial meat-type chickens with clinical outbreak of Clostridium infections. In addition to the genes encoding EF-Tu and PFO, C. perfringens alpha-toxin and necrotic enteritis B-like (NetB) toxin were also expressed in Escherichia coli and their corresponding recombinant proteins were purified. Using the four recombinant proteins as target antigens in ELISA immunoassays, high serum antibody titers were observed not only in chickens with clinical signs of Clostridium infections, but also in apparently healthy animals from the same disease-endemic farm. By contrast, no antibodies against any of the proteins were present in the serum of a specific pathogen-free bird. In ELISA using recombinant proteins of C. perfringens, the levels of anti-bacterial protein antibodies were also higher in chickens which were experimentally induced to show NE clinical signs after co-infection with C. perfringens and Eimeria maxima compared with uninfected controls. These results show that two antigenic C. perfringens proteins, EF-Tu and PFO can be useful detection antigens for C. perfringens-afflicted infections in commercial poultry.  相似文献   

13.

Background

Etiology of hemorrhagic gastroenteritis (HGE) syndrome in dogs is unknown and histopathologic and microbial investigations have only been performed post mortem.

Objective

To identify characteristic intra vitam endoscopic and histologic mucosal lesions, as well as bacterial species, within the mucosa of dogs with HGE.

Animals

Ten dogs diagnosed with HGE were included. Eleven dogs with gastroduodenoscopy and different intestinal diseases were used as controls for microbial changes. Dogs pretreated with antibiotics or diagnosed with any disease known to cause bloody diarrhea were excluded from the study.

Methods

In this prospective study, gastrointestinal biopsies were collected from 10 dogs with HGE. Endoscopic and histologic changes were assessed according to WSAVA guidelines. Biopsies from the stomach, duodenum, ileum, and colon were investigated by histology and by immunohistochemistry for the presence of Clostridium spp. and parvovirus. The first duodenal biopsy taken with a sterile forceps was submitted for bacterial culture.

Results

Acute mucosal lesions were only found in the intestines, not in the stomach. Clostridium spp., identified as Clostridium perfringens in 6/9 cases, were detected on the small intestinal mucosa in all dogs with HGE, either by culture or immunohistopathology. In the control group, C. perfringens could only be cultured in one of 11 dogs.

Conclusions and Clinical Importance

The results of this study demonstrate an apparent association between C. perfringens and the occurrence of acute hemorrhagic diarrhea. The term “HGE,” which implies the involvement of the stomach, should be renamed as “acute hemorrhagic diarrhea syndrome.”  相似文献   

14.
A multiplex polymerase chain reaction (PCR) assay, developed to detect the alpha-toxin and enterotoxin genes (cpa and cpe, respectively) of Clostridium perfringens, was used to identify enterotoxigenic isolates of this organism from feces and intestinal contents of pigs and from feed samples from pig farms in Iowa. The organism was grown on tryptose-sulfite-cycloserine (TSC) agar, TSC agar without egg-yolk, sheep blood agar, or in brain heart infusion broth or cooked meat medium. DNA was extracted by boiling and the PCR assay was carried out using reagents from a commercial kit. The 319 bp amplification product of cpa and the 364 bp product of cpe were visualized under UV light after electrophoresis in a 2% agarose gel containing ethidium bromide. The average sensitivity of the assay, determined on artificially contaminated feces, was 9.2×104 colony forming units per gram. Assay of 97 isolates from feces and intestinal contents revealed cpa in 89, but all were negative for cpe. While 28% of the 442 total samples cultured yielded C. perfringens, only 5% of 298 fecal or intestinal contents samples were positive upon direct examination by the PCR assay. Ninety-one and eight-tenths % of isolates with the phenotype of C. perfringens were cpa positive by PCR. Forty-three percent of feed samples were culture positive, while 48.3% were PCR positive for cpa. None of these were cpe positive. We conclude that PCR is a useful assay for rapid detection of C. perfringens in feed, and for confirmation of the identity of isolates presumed to be C. perfringens.  相似文献   

15.
We previously reported that Clostridium perfringens in vivo proliferation and alpha-toxin gene expression were highly correlated, both progressing in a parabolic curve pattern during the development of necrotic enteritis (NE). The present study investigated the response of dominant ileal bacteria in abundance to C. perfringens infection using PCR-based denaturing gradient gel electrophoresis (DGGE) and quantitative PCR (QPCR) techniques. Chickens were fed antibiotic-medicated (bacitracin, 55 mg/kg) or non-medicated diets, and were challenged with C. perfringens through the diet at 18 days of age. Ileal digesta was collected daily before and after the challenge for 5 days. Bacterial profiles of PCR-DGGE from both bacitracin-treated and untreated chickens responding to clostridial infection were analyzed by the principal component analysis (PCA) and partial least squares discriminant analysis (PLS-DA). Treatment-related differences in PCR-DGGE bacterial profiles on day 2 post-infection (PI) were detected. Subsequent QPCR assays identified changes in the abundance of lactobacilli, L. aviarius in particular. Changes in both populations correlated negatively with the population of C. perfringens in bacitracin-untreated group of chickens that displayed a high incidence of NE lesions. The results indicated that L. aviarius was suppressed by C. perfringens infection. This observation warrants further studies on the mechanisms underlying the ecological change and to assist in further development of novel probiotics to control NE disease.  相似文献   

16.
Laboratory surveillance data from the Animal Health Laboratory, University of Guelph, on the etiological diagnoses of neonatal diarrhea in piglets were analyzed to determine the relative importance and trends of different enteric pathogens in Ontario. A total of 237 cases, including live and dead 1- to 7-day-old piglets, were submitted for diagnosis of gastrointestinal illness between 2001 and 2010. The combined frequencies for cases of gastrointestinal illness involving Escherichia coli, Clostridium perfringens type A, rotavirus, and Clostridium difficile, either as single pathogens or a complex of pathogens, accounted for 56% of the total cases. In a total of 33% of cases of gastrointestinal illness, an etiological agent was not identified. The frequency of cases diagnosed with enterotoxigenic E. coli was decreased from 2007. Cases submitted in 2010 were more likely to be diagnosed with C. perfringens type A compared to cases submitted in 2002 to 2007 (P < 0.05). There was a significant trend for cases submitted in the winter to be diagnosed with C. perfringens type A, enterotoxigenic E. coli, rotavirus, and Cystoisospora suis (formerly Isospora suis) (P < 0.05). Enterotoxigenic E. coli was less likely diagnosed if C. difficile, C. perfringens, or rotavirus were detected (P < 0.05). Younger piglets were more likely to be diagnosed with C. perfringens type A (P < 0.05) and C. difficile (P < 0.05) than older piglets. This study shows that E. coli, C. perfringens type A, rotavirus, and C. difficile are enteric pathogens of concern for Ontario swine farrowing operations and further research is required to understand the reasons for the cases that are not diagnosed.  相似文献   

17.
Clostridium perfringens has been implicated as a cause of diarrhea in dogs. The objectives of this study were to compare 2 culture methods and to evaluate a multiplex polymerase chain reaction (PCR) assay to detect C. perfringens toxin genes alpha (α), beta (β ), beta 2 (β2), epsilon (ɛ), iota (ι), and C. perfringens enterotoxin (cpe) from canine isolates. Fecal samples were collected from clinically normal non-diarrheic (ND) dogs, (n = 105) and diarrheic dogs (DD, n = 54). Clostridium perfringens was isolated by directly inoculating stool onto 5% sheep blood agar (SBA) and enrichment in brain-heart infusion (BHI) broth, followed by inoculation onto SBA. Isolates were tested by multiplex PCR for the presence of α, β, β2, ɛ, ι, and cpe genes. C. perfringens was isolated from 84% of ND samples using direct culture and from 87.6% with enrichment (P = 0.79). In the DD group, corresponding isolation rates were 90.7% and 93.8% (P = 0.65). All isolates possessed the α toxin gene. Beta (β), β2, ɛ, ι, and cpe toxin genes were identified in 4.5%, 1.1%, 3.4%, 1.1%, and 14.8% of ND isolates, respectively. In the DD group, β and β2 were identified in 5%, ɛ and ι were not identified, and the cpe gene was identified in 16.9% of isolates. Enrichment with BHI broth did not significantly increase the yield of C. perfringens, but it did increase the time and cost of the procedure. C. perfringens toxin genes were present in equal proportions in both the ND and DD groups (P ≤ 0.15 to 0.6). Within the parameters of this study, culture of C. perfringens and PCR for toxin genes is of limited diagnostic usefulness due to its high prevalence in normal dogs and the lack of apparent difference in the distribution of toxin genes between normal and diarrheic dogs.  相似文献   

18.
A novel toxin, NetB, has recently been identified in virulent avian Clostridium perfringens isolates and shown to be an essential virulence factor in a clinical necrotic enteritis isolate. To assess whether NetB is more generally associated with avian necrotic enteritis isolates we have screened a range of C. perfringens strains from geographically diverse locations for both the presence and expression of the netB gene. Forty-four isolates were derived from necrotic enteritis disease cases from Australia, Belgium, Denmark and Canada and 55 isolates from healthy chickens from Australia and Belgium. The majority of strains isolated from necrotic enteritis-affected birds were netB positive (70%) and there was an absolute correlation between the presence of netB and in vitro expression of the NetB protein. Only two of the C. perfringens isolates from healthy chickens carried netB. Sequencing of the netB gene from 23 positive isolates showed that NetB is highly conserved, with only one predicted amino acid (A168T) difference, in six isolates, compared to the published sequence. This change did not alter the in vitro activity of the NetB toxin. The gene encoding the recently discovered TpeL toxin was also screened using PCR and only found in a small proportion of NetB-positive isolates from diseased birds. A selection of NetB-negative isolates, originating from diseased birds, was unable to cause disease in a necrotic enteritis induction model. This study provides further evidence that NetB is important in pathogenesis and advances our current understanding of C. perfringens virulence factors in avian necrotic enteritis.  相似文献   

19.
To evaluate the relative importance of the various enteropathogens causing neonatal diarrhea in Quebec farrowing operations, observations were made on 749 diarrheic pigs from 325 outbreaks of diarrhea. They were one to 15 days of age, and were obtained alive for necropsy generally within 48 hours of the onset of diarrhea. Some pigs were from severe, explosive outbreaks of diarrhea with high morbidity and mortality rates, while others were from herds with chronic neonatal diarrhea with lower morbidity and mortality rates. A combination of bacteriological, virological and histological methods were used to study the pigs.

Viruses were incriminated in 60%, bacteria in 23% and coccidia in 15.3% of the 325 diarrhea outbreaks. Transmissible gastroenteritis virus was by far the most common enteropathogen with a prevalence of 52%; rotavirus was implicated in 9.2% of the outbreaks while adenovirus was incriminated in 0.30% of the outbreaks. Enterotoxigenic Escherichia coli were involved in 22.4% of the cases while Clostridium perfringens type C was an occasional finding. Coccidia involved in our herds were identified as Isospora suis. The disease was attributed to infection with a single etiologic agent in 590 diarrheic pigs (78%) while combinations of agents were present in only 90 (12%).

The age-specific occurrence of the various enteropathogens was evaluated. Transmissible gastroenteritis virus was the most common enteropathogen in all age groups. Colibacillosis was common in pigs which became diarrheic under five days of age; in this age group, the enterotoxigenic E. coli were frequently found alone, but were usually combined with other agents in older pigs. The prevalence of coccidia was high in pigs which became diarrheic between five and 15 days of age. Rotavirus infection was common in diarrheic pigs older than ten days of age. Although individual baby pigs were commonly infected with a single enteropathogen, it was very common to see more than one agent involved in an outbreak of diarrhea, particularly when pigs of different ages were affected.

Observations on the occurrence of the enteropathogens according to the seasons were also made. Occurrence of transmissible gastroenteritis was throughout the year with the highest prevalence during the fall, winter and spring months. Colibacillosis and coccidiosis were more common in the summer, fall and early winter months with the lowest prevalence in the spring months.

  相似文献   

20.
Clostridia are not normally considered to be zoonotic pathogens, although many species affect both humans and domestic animals. Three cases in which organisms occur, possibly via direct or indirect transmission, in both food animals and humans are considered here. Strains of Clostridium perfringens that produce enterotoxin (CPE) are typically transmitted to humans in contaminated, improperly handled foods. Pathogenesis is based upon action of CPE in the intestine, and disease is usually self-limiting. Infection of domestic animals by CPE-producing C. perfringens is uncommon. C. perfringens type C is best known as a pathogen of neonatal domestic animals, which acquire the infection from the dam. The course may be peracute, and prevention by vaccination of the dam is universally advocated. Humans consuming meat contaminated with type C may develop enteritis necroticans, with segmental hemorrhagic and necrotic jejunitis, which must usually be treated by bowel resection. Clostridium difficile is a pathogen of both humans and domestic animals. Examination of retail meats by bacteriologic culture has revealed genotypes of C. difficile that in many cases are identical to those from food animals and diseased humans. Transmission, food animals to foods to humans, has not been documented.  相似文献   

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