Clostridium Piliforme Research Articles

Molecular Diagnosis Of Clostridium piliforme, The Causative Agent Of Tyzzer’s Disease In Mice And Rats

Tyzzer’s disease, caused by Clostridium piliforme (C. piliforme), occurs in many species of mammals mainly in rodents, rabbits and foals is an acute, epizootic bacterial disease that can result in mortality. In our study, C. piliforme was investigated in feces samples from mice and rats in a laboratory experimental animals center by PCR technique. C. piliforme was detected in 44 (83.01%) of a total of 53 mouse feces of different ages. Of the mice found positive, 28 (73.6%) were female and 16 (88.8%) were male. C. piliforme was detected in 40 (90.9%) of a total of 44 rats feces of different ages. Of the rats found positive, 25 (96.1%) were female and 15 (83.3%) were male. C. piliforme, the causative agent of Tyzzer's disease, was detected at a high rate in mice and rats examined by the classical PCR method. When evaluated in terms of gender, 28 (73.6%) of the 40 mice positive for Tyzerr's disease were female and 16 (88.8%) were male; While 25 (96.1%) of the rats were female, 15 (83.3%) were male. As a result, Tyzerr's disease caused by C. piliforme was detected at a high rate in mice and rats by classical PCR. When evaluated by age, the disease was detected to be higher in mice at the ages of 4, 5 and 8, and in rats at the ages of 4, 5, 6 and 7. Due to the reliability of the analyses and the high risk of transmission to other animals in centers where laboratory animals are raised, Tyzzer's disease should be checked and necessary precautions should be taken to prevent the disease.

Establishment and application of a loop-mediated isothermal amplification-lateral flow dipstick (LAMP-LFD) method for detecting Clostridium piliforme.

Clostridium piliforme (causative agent of Tyzzer disease) infects various animals, including primates, and hence a threat to animal and human health worldwide. At present, it is detected using traditional methods, such as path morphology, polymerase chain reaction and enzyme-linked immunosorbent assay. Therefore, it is necessary to develop convenient, efficient visual molecular biological methods for detecting C. piliforme. To establish a method with good specificity, high sensitivity and simple operation for the detection of C. piliforme. In this study, we designed internal and external primers based on the conserved 23S rRNA region of C. piliforme to develop a biotin-labelled diarrhoea-suffered loop-mediated isothermal amplification (LAMP) system for detecting of C. piliforme and assessed the specificity, sensitivity and repeatability of the LAMP system. The LAMP system did not exhibit cross-reactivity with 24 other common pathogenic species, indicating that it had good specificity. The minimum concentration of sensitivity was 1×10-7 ng/μL. Mouse models (Meriones unguiculatus) of Tyzzer disease were established and a LAMP-lateral flow dipstick (LAMP-LFD) was developed for detecting C. piliforme. The detection rate of C. piliforme was 5.08% in clean-grade animals and 9.96% in specific-pathogen-free-grade animals from Jiangsu, Zhejiang and Shanghai. In addition, the detection rates of C. piliforme were 10.1%, 8.6% and 20%, in animals from Hangzhou, Wenzhou and Shaoxing, respectively. The detection rate of C. piliforme was higher in experimental animals used in schools than in those used in companies and research institutes. The LAMP-LFD method established in this study can be used to detect C. piliforme in animals handled in laboratory facilities of universities, pharmaceutical enterprises and research and development institutions.

Neurologic and cutaneous infection by Clostridium piliforme in a kitten with systemic Tyzzer disease.

Tyzzer disease (TD) is a highly fatal condition of animals caused by Clostridium piliforme and characterized pathologically by enteritis, hepatitis, myocarditis, and occasionally encephalitis. Cutaneous lesions have been reported only rarely in animals with TD, and infection of the nervous system has not been described in cats, to our knowledge. We describe here neurologic and cutaneous infection by C. piliforme in a shelter kitten with systemic manifestations of TD and coinfection with feline panleukopenia virus. Systemic lesions included necrotizing typhlocolitis, hepatitis, myocarditis, and myeloencephalitis. The cutaneous lesions consisted of intraepidermal pustular dermatitis and folliculitis, with necrosis of keratinocytes and ulceration. Clostridial bacilli were identified within the cytoplasm of keratinocytes by fluorescence in situ hybridization, and a PCR assay was positive for C. piliforme. C. piliforme can infect keratinocytes leading to cutaneous lesions in cats with the location suggesting direct contact with contaminated feces as a route of infection.

Tyzzer disease in 19 preweaned orphaned kittens.

Clostridium piliforme, the agent of Tyzzer disease, has traditionally not been considered a major pathogen of cats. We queried the database of the Pathology Service of the Veterinary Medical Teaching Hospital, University of California-Davis, for kittens <6-mo-old autopsied between 2000-2021 that had colitis, hepatitis, and/or myocarditis; 37 cases met the search criteria. Sections of colon, liver, and heart from these 37 cats were stained with modified Steiner; 19 of 37 (51%) cases had intraepithelial, Steiner-positive rods compatible with C. piliforme in at least one organ, confirming Tyzzer disease. The affected age range was 7-42 d (median: 17.5 d). Eighteen were orphaned kittens. Colitis was the major lesion (18 of 19) followed by random hepatitis (11 of 19). Perianal dermatitis with intraepithelial stacked rods was seen in 2 of 19. Myocarditis was not evident in any of the cases. A PCR assay for C. piliforme on 10 selected cases using formalin-fixed, paraffin-embedded (FFPE) blocks was positive or suspected in colon (5 of 10), liver (5 of 10), and heart (1 of 10). The modified Steiner stain was more sensitive in the detection of bacteria than PCR on FFPE samples. Fifteen kittens had comorbidities. A weakened immune state caused by maternal, environmental, infectious, and/or nutritional causes is speculated to have contributed to disease onset. We found that Tyzzer disease is more common than previously believed in orphaned kittens and should be considered in kittens with colitis and/or hepatitis.

Unique Presentations of Burkholderia gladioli Infections in Several Strains of Immunocompromised Mice.

Four strains of experimentally naïve mice (NOD. Cg-Prkdc scid Il2rg tm1Wjl /SzJ [NSG], NOD. Cg- Rag1 tm1Mom Il2rg tm1Wjl /SzJ [NRG], B6.129S(Cg)-Stat1 tm1Dlv/J [STAT1 -/-], and B6.129S7- Ifngr1 tm1Agt/J[IFNγR -/-] housed in a barrier facility developed unusual and seemingly unrelated clinical signs. Young NSG/NRG mice (n = 49, mean age = 4 ± 0.4 mo) exhibited nonspecific clinical signs of moderate-to-severe lethargy, hunched posture, decreased body condition, and pallor. In contrast to the NSG/NRG mice, the STAT1-/- and IFNγ R-/- mice (n = 5) developed large subcutaneous abscesses on the head and neck. These mice were euthanized, and samples were collected for culture. NSG/NRG mice had moderate-markedly enlarged livers (20 of 49, 40%) and spleens (17 of 49, 35%). The livers contained multiple, variably-sized, tan regions throughout all lobes. Histology revealed necrotizing hepatitis (13 of 17, 77%), splenic and hepatic extramedullary hematopoiesis (17 of 17, 100%), glomerular histiocytosis (6 of 17, 35%), and metritis (6 of 11, 55%) with perivascular inflammation, suggesting hematogenous spread Differentials for these lesions included mouse hepatitis virus, ectromelia virus, Pseudomonas aeruginosa, Salmonella spp., and Clostridium piliforme. Burkholderia gladioli was cultured from liver lesions and subcutaneous abscesses and confirmed with 16S ribosomal RNA sequencing. After completing systematic testing of the environment, failure of the water autoclave cycle was suspected as the cause of the outbreak. To address the situation, individually ventilated racks were sanitized and new breeders were purchased; these actions dramatically reduced B. gladioli infections. The current literature contains few reports of B. gladioli infections in immunocompromised mice, and its typical presentation is torticollis and rolling. B. gladioli infection is a potential differential for subcutaneous abscesses, hepatitis, and splenomegaly in immunocompromised mice. Careful monitoring of sterilization techniques is essential to prevent such infections in a barrier facility.

Successful management of an outbreak of Tyzzer's disease on a Thoroughbred breeding farm in central Kentucky; use of sorbitol dehydrogenase to identify sub‐clinical cases

SummaryBackgroundTyzzer's disease is rare and usually fatal in the foal. Outbreaks are especially rare and have high educational value. Long‐term recovery of multiple survivors and the use of sorbitol dehydrogenase (SDH) as a time‐sensitive screening test during an outbreak have not been reported. The epidemiology of Clostridium piliforme acute necrotising hepatitis is enigmatic because the original source is unknown.ObjectivesThe aims of this study were to present highly variable clinicopathologic findings, clinical presentation, progression and challenges, diagnostic and treatment protocols of two confirmed and two presumptive Tyzzer's cases, to determine the utility of plasma SDH measurement in the identification of subclinical or early Tyzzer's disease in the on‐farm population and to identify carrier animals.Study designCase series. Prospective cohort study. Case–control study.MethodsA cut‐off value for SDH was determined based on values observed in the critically ill foals and applied to 39 on‐farm foals (114 samplings). SDH values &gt;20 IU/L prompted prophylactic treatment. Faecal PCR testing was performed on the surviving foals, the dams of all affected foals and the dams of foals with SDH values &gt;20 IU/L. A control group of dams with matched foaling dates was sampled.ResultsThe screening test identified one subclinical hepatitis case, in the youngest foal on the farm. No further clinical cases occurred. SDH lacked sensitivity in one confirmed case and specificity in foals &gt;40 days of age. All faecal PCR samples were negative.Main limitationsSorbitol dehydrogenase sampling of on‐farm foals may have been biased by economic value or athletic prospect.ConclusionsTwo foals were successfully treated; one is a successful athlete. Refractory hypoglycaemia presented the greatest clinical challenge and required aggressive treatment. The source of infection and carrier status remain unknown. SDH lacks specificity but might be the most sensitive test available during a Tyzzer's disease outbreak.

Clostridium piliforme and canine distemper virus coinfection in 2 domestic dog littermates and a gray fox kit.

Concurrent Clostridium piliforme and canine distemper virus (CDV) infection was diagnosed in 2 canine littermates and 1 gray fox kit from Texas, USA. In all 3 animals, intracytoplasmic, filamentous bacteria, consistent with C. piliforme, were present along the margins of foci of hepatic necrosis. Additional histologic findings included intracytoplasmic and intranuclear inclusion bodies in bile duct and bronchial epithelial cells of the fox kit, and mild intestinal necrosis in 1 puppy. PCR assays confirmed the presence of C. piliforme in all 3 animals, CDV in both puppies, and canine parvovirus in 1 puppy. Fluorescent antibody testing confirmed the presence of CDV in the fox kit. Concurrent canine distemper and Tyzzer disease in canine littermates and the gray fox has not been reported previously, to our knowledge.

Clostridial Diseases of Horses: A Review.

The clostridial diseases of horses can be divided into three major groups: enteric/enterotoxic, histotoxic, and neurotoxic. The main enteric/enterotoxic diseases include those produced by Clostridium perfringens type C and Clostridioides difficile, both of which are characterized by enterocolitis. The main histotoxic diseases are gas gangrene, Tyzzer disease, and infectious necrotic hepatitis. Gas gangrene is produced by one or more of the following microorganisms: C. perfringens type A, Clostridium septicum, Paeniclostridium sordellii, and Clostridium novyi type A, and it is characterized by necrotizing cellulitis and/or myositis. Tyzzer disease is produced by Clostridium piliforme and is mainly characterized by multifocal necrotizing hepatitis. Infectious necrotic hepatitis is produced by Clostridium novyi type B and is characterized by focal necrotizing hepatitis. The main neurotoxic clostridial diseases are tetanus and botulism, which are produced by Clostridium tetani and Clostridium botulinum, respectively. Tetanus is characterized by spastic paralysis and botulism by flaccid paralysis. Neither disease present with specific gross or microscopic lesions. The pathogenesis of clostridial diseases involves the production of toxins. Confirming a diagnosis of some of the clostridial diseases of horses is sometimes difficult, mainly because some agents can be present in tissues of normal animals. This paper reviews the main clostridial diseases of horses.

Antibiotic resistance and potential bacterial pathogens identified in red deer's faecal DNA.

In the last decades, the wildlife-human interface has been increasing due to several anthropogenic factors. Therefore, it is crucial to be aware of the impact of these new dynamics on the health of wild animals and their associated zoonotic disease risks. This study aimed to characterize the faecal microbiota of two populations of red deer (Cervus elaphus) by metabarcoding, with a particular focus on potential human and veterinary pathogens, and to perform an assessment of antibiotic resistance genes (ARGs) occurrence. The faecal microbiota of red deer was assessed by metabarcoding using the 16S rRNA marker, and OTUs of the genera Treponema, Yersinia, Clostridium, Mycobacterium, and Rickettsia were identified. Two of them affiliated with species more commonly regarded as pathogens (Clostridiumpiliforme and Yersinia enterocolitica). The quantification of ARGs was performed by quantitative real-time PCR, using a metagenomic approach, and the most abundant genes were found to be blaTEM , sul1, tetracycline resistance genes (tetW, tetO, and tetQ) and ermF. From these, tetO and tetW are rank II ARGs, which were recently considered future threats for human health. Our results suggest the need for screening programs for the occurrence of pathogens and ARGs in wildlife and particularly in-game species.

Surveillance for diseases, pathogens, and toxicants of muskrat (Ondatra zibethicus) in Pennsylvania and surrounding regions.

Using diagnostic data and contemporary sampling efforts, we conducted surveillance for a diversity of pathogens, toxicants, and diseases of muskrats (Ondatra zibethicus). Between 1977 and 2019, 26 diagnostic cases were examined from Kansas and throughout the Southeast and Mid-Atlantic, USA. We identified multiple causes of mortality in muskrats, but trauma (8/26), Tyzzer’s disease (5/6), and cysticercosis (5/26) were the most common. We also conducted necropsies, during November 2018—January 2019 Pennsylvania muskrat trapping season, on 380 trapper-harvested muskrat carcasses after the pelt was removed. Tissue samples and exudate were tested for presence of or exposure to a suite of pathogens and contaminants. Gastrointestinal tracts were examined for helminths. Intestinal helminths were present in 39.2% of necropsied muskrats, with Hymenolepis spp. (62%) and echinostome spp. (44%) being the most common Molecular testing identified a low prevalence of infection with Clostridium piliforme in the feces and Sarcocystis spp. in the heart. We detected a low seroprevalence to Toxoplasma gondii (1/380). No muskrats were positive for Francisella tularensis or Babesia spp. Cysticercosis was detected in 20% (5/26) of diagnostic cases and 15% (57/380) of our trapper-harvested muskrats. Toxic concentrations of arsenic, cadmium, lead, or mercury were not detected in tested liver samples. Copper, molybdenum, and zinc concentrations were detected at acceptable levels comparative to previous studies. Parasite intensity and abundance were typical of historic reports; however, younger muskrats had higher intensity of infection than older muskrats which is contradictory to what has been previously reported. A diversity of pathogens and contaminants have been reported from muskrats, but the associated disease impacts are poorly understood. Our data are consistent with historic reports and highlight the wide range of parasites, pathogens and contaminants harbored by muskrats in Pennsylvania. The data collected are a critical component in assessing overall muskrat health and serve as a basis for understanding the impacts of disease on recent muskrat population declines.

Bacterial and viral enterocolitis in horses: a review.

Enteritis, colitis, and enterocolitis are considered some of the most common causes of disease and death in horses. Determining the etiology of these conditions is challenging, among other reasons because different causes produce similar clinical signs and lesions, and also because some agents of colitis can be present in the intestine of normal animals. We review here the main bacterial and viral causes of enterocolitis of horses, including Salmonella spp., Clostridium perfringens type A NetF-positive, C. perfringens type C, Clostridioides difficile, Clostridium piliforme, Paeniclostridium sordellii, other clostridia, Rhodococcus equi, Neorickettsia risticii, Lawsonia intracellularis, equine rotavirus, and equine coronavirus. Diarrhea and colic are the hallmark clinical signs of colitis and enterocolitis, and the majority of these conditions are characterized by necrotizing changes in the mucosa of the small intestine, colon, cecum, or in a combination of these organs. The presumptive diagnosis is based on clinical, gross, and microscopic findings, and confirmed by detection of some of the agents and/or their toxins in the intestinal content or feces.

Clostridium piliforme infection (Tyzzer disease) in horses: retrospective study of 25 cases and literature review.

Tyzzer disease (TD) is caused by Clostridium piliforme, a gram-negative and obligate intracellular bacterium. The disease occurs in multiple species. A triad of lesions, namely colitis, hepatitis, and myocarditis, is described in cases of TD in some species, such as rats and mice. We carried out a retrospective analysis of 25 equine cases with a diagnosis of TD; 24 of 25 cases occurred in foals <45 d old; the remaining foal was 90 d old. There were 12 males and 12 females; no sex information was available for one foal. The affected breeds were Quarter Horse, Thoroughbred, Arabian, Paint, and Hanoverian. Most of the cases (19 of 25) occurred in the spring. There were 9 cases of sudden death; the remaining animals had diarrhea, fever, distended abdomen, depression, weakness, non-responsiveness, and/or recumbency. Gross findings included icterus, hepatomegaly with acinar pattern, serosal hemorrhages, pulmonary edema, and/or fluid content in small and large intestine. Microscopically, all foals had severe, multifocal, necrotizing hepatitis. Necrotizing lymphohistiocytic colitis was observed in 10 of 25 foals, and multifocal necrotizing myocarditis was found in 8 of 25. Gram-negative, Steiner-positive, intracytoplasmic filamentous bacteria were observed in hepatocytes, enterocytes, and myocardiocytes, respectively. PCR detected C. piliforme DNA in the liver (24 of 24), colon (20 of 24), and heart (5 of 25). Our results indicate that necrotic hepatitis is the hallmark of TD in horses; the so-called triad of lesions is not a consistent characteristic of the disease in this species.

Pathobiology and diagnosis of clostridial hepatitis in animals.

Clostridia can cause hepatic damage in domestic livestock, and wild and laboratory animals. Clostridium novyi type B causes infectious necrotic hepatitis (INH) in sheep and less frequently in other species. Spores of C. novyi type B can be present in soil; after ingestion, they reach the liver via portal circulation where they persist in phagocytic cells. Following liver damage, frequently caused by migrating parasites, local anaerobic conditions allow germination of the clostridial spores and production of toxins. C. novyi type B alpha toxin causes necrotizing hepatitis and extensive edema, congestion, and hemorrhage in multiple organs. Clostridium haemolyticum causes bacillary hemoglobinuria (BH) in cattle, sheep, and rarely, horses. Beta toxin is the main virulence factor of C. haemolyticum, causing hepatic necrosis and hemolysis. Clostridium piliforme, the causal agent of Tyzzer disease (TD), is the only gram-negative and obligate intracellular pathogenic clostridia. TD occurs in multiple species, but it is more frequent in foals, lagomorphs, and laboratory animals. The mode of transmission is fecal-oral, with ingestion of spores from a fecal-contaminated environment. In affected animals, C. piliforme proliferates in the intestinal mucosa, resulting in necrosis, and then disseminates to the liver and other organs. Virulence factors for this microorganism have not been identified, to date. Given the peracute or acute nature of clostridial hepatitis in animals, treatment is rarely effective. However, INH and BH can be prevented, and should be controlled by vaccination and control of liver flukes. To date, no vaccine is available to prevent TD.

Multiplex Immunochromatographic Assay for Serologic Diagnosis of Major Infectious Diseases in Laboratory Mice.

Serologic monitoring of infectious diseases is important for microbial control in colonies of laboratory mice. Rapid and simple tests that do not require killing animals are valuable for this purpose. In this study, we developed a multiplex immunochromatographic assay (ICA) for detection of antibodies to mouse hepatitis virus (MHV), Sendai virus (also known as hemagglutinating virus of Japan [HVJ]), and Clostridium piliforme (The pathogen that causes Tyzzer disease), which are major infectious diseases in mice. For this assay, an ICA strip was put into a microtube containing 150 μL PBS and either 0.75 μL mouse serum or 1.5 μL whole blood. Binding antibodies were visualized by using protein A-conjugated colloidal gold. Under these conditions, multiplex ICA simultaneously and specifically detected antibodies to multiple antigens. To evaluate the sensitivity and specificity of multiplex ICA, positive serum samples for each infectious disease were used. Sensitivities of the multiplex ICA test for MHV, HVJ, and C. piliforme were 100%, 100%, and 90%, respectively. No nonspecific reaction was observed in any of the 30 positive sera. In addition, 10 samples of uninfected sera did not show any bands except for the control line. These observations indicate high specificity of the multiplex ICA test. Moreover, the multiplex ICA could be applied to diluted blood. These results indicate that the multiplex ICA is appropriate for rapid, simple, and safe serologic testing of laboratory mice.

Bacterial species to be considered in quality assurance of mice and rats.

Bacteria are relevant in rodent quality assurance programmes if (a) the animals are at risk and (b) presence in the animals makes a difference for animal research or welfare, for example because the agent regulates clinical disease progression or impacts its host in other ways. Furthermore, zoonoses are relevant. Some bacterial species internationally recommended for the health monitoring of rats and mice, that is, Citrobacter rodentium, Corynebacterium kutscheri, Salmonella spp. and Streptococcus pneumonia, are no longer found in either laboratory or pet shop rats or mice, while there is still a real risk of impact on animal research and welfare from Filobacterium rodentium, Clostridium piliforme, Mycoplasma spp., Helicobacter spp. and Rodentibacter spp., while Streptobacillus moniliformis may be considered a serious zoonotic agent in spite of a very low risk. Modern molecular techniques have revealed that there may, depending on the research type, be equally good reasons for knowing the colony status of some commensal bacteria that are essential for the induction of specific rodent models, such as Alistipes spp., Akkermansia muciniphila, Bifidobacterium spp., Bacteroides fragilis, Bacteroides vulgatus, Faecalibacterium prausnitzii, Prevotella copri and segmented filamentous bacteria. In future, research groups should therefore consider the presence or absence of a short list of defined bacterial species relevant for their models. This list can be tested by cost-effective sequencing or even a simple multiple polymerase chain reaction approach, which is likely to be cost-neutral compared to more traditional screening methods.

Seroprevalence of Rodent Pathogens in Wild Rats from the Island of St. Kitts, West Indies.

Simple SummaryThe role of rodents in the transmission of many diseases is widely known. Wild rats abundant in urban environments may transmit diseases to humans and other animals, including laboratory rodents used for biomedical research in research facilities, possibly compromising research data. In order to gather information about the various diseases present around such facilities, it is important to conduct routine surveillance of wild rodents in the area. In this pilot study, we surveyed 22 captured wild rats (Rattus norvegicus and Rattus rattus) from the Caribbean island of St. Kitts for 19 microorganisms. Information gained from such surveillance data would be beneficial in assessing regional public health risks and when implementing routine laboratory rodent health monitoring protocols.A pilot seroprevalence study was conducted to document exposure to selected pathogens in wild rats inhabiting the Caribbean island of St. Kitts. Serum samples collected from 22 captured wild rats (Rattus norvegicus and Rattus rattus) were tested for the presence of antibodies to various rodent pathogens using a rat MFI2 serology panel. The samples were positive for cilia-associated respiratory bacillus (13/22; 59.1%), Clostridium piliforme (4/22; 18.2%), Mycoplasma pulmonis (4/22; 18.2%), Pneumocystis carinii (1/22; 4.5%), mouse adenovirus type 2 (16/22; 72.7%), Kilham rat virus (15/22; 68.2%), reovirus type 3 (9/22; 40.9%), rat parvovirus (4/22; 18.2%), rat minute virus (4/22; 18.2%), rat theilovirus (2/22; 9.1%), and infectious diarrhea of infant rats strain of group B rotavirus (rat rotavirus) (1/22; 4.5%). This study provides the first evidence of exposure to various rodent pathogens in wild rats on the island of St. Kitts. Periodic pathogen surveillance in the wild rat population would be beneficial in assessing potential regional zoonotic risks as well as in enhancing the current knowledge when implementing routine animal health monitoring protocols in facilities with laboratory rodent colonies.

Mortality Due to Tyzzer's Disease of Muskrats (Ondatra zibethicus) in Northern Ohio, USA

In 2017, we investigated a mortality event of muskrat (Ondatra zibethicus) in northwest Ohio, US, and determined the causes of death to be from Tyzzer's disease due to Clostridium piliforme and Klebsiella pneumoniae septicemia. The gross presentation resembled tularemia, which highlighted the importance of a complete diagnostic investigation.

Comparative pathogenesis of enteric clostridial infections in humans and animals

Several enteric clostridial diseases can affect humans and animals. Of these, the enteric infections caused by Clostridium perfringens and Clostridium difficile are amongst the most prevalent and they are reviewed here. C. perfringens type A strains encoding alpha toxin (CPA) are frequently associated with enteric disease of many animal mammalian species, but their role in these diseased mammals remains to be clarified. C. perfringens type B encoding CPA, beta (CPB) and epsilon (ETX) toxins causes necro-hemorrhagic enteritis, mostly in sheep, and these strains have been recently suggested to be involved in multiple sclerosis in humans, although evidence of this involvement is lacking. C. perfringens type C strains encode CPA and CPB and cause necrotizing enteritis in humans and animals, while CPA and ETX producing type D strains of C. perfringens produce enterotoxemia in sheep, goats and cattle, but are not known to cause spontaneous disease in humans. The role of C. perfringens type E in animal or human disease remains poorly defined. The newly revised toxinotype F encodes CPA and enterotoxin (CPE), the latter being responsible for food poisoning in humans, and the less prevalent antibiotic associated and sporadic diarrhea. The role of these strains in animal disease has not been fully described and remains controversial. Another newly created toxinotype, G, encodes CPA and necrotic enteritis toxin B-like (NetB), and is responsible for avian necrotic enteritis, but has not been associated with human disease. C. difficile produces colitis and/or enterocolitis in humans and multiple animal species. The main virulence factors of this microorganism are toxins A, B and an ADP-ribosyltransferase (CDT). Other clostridia causing enteric diseases in humans and/or animals are Clostridium spiroforme, Clostridium piliforme, Clostridium colinum, Clostridium sordellii, Clostridium chauvoei, Clostridium septicum, Clostridium botulinum, Clostridium butyricum and Clostridium neonatale. The zoonotic transmission of some, but not all these clostridsial species, has been demonstrated.

Tyzzer's Disease in Free-Ranging Passerine Birds in California, USA.

Tyzzer's disease was diagnosed as the cause of mortality in free-ranging hatch-year passerine birds in Southern California, US. Birds presented with ataxia, tremors, and opisthotonos and died or were euthanized. Postmortem examination of four birds identified encephalitis on microscopy with characteristic stacked, slender bacterial rods visible with special stains. Infection with Clostridium piliforme was confirmed by real-time PCR.

Efficacy of Soiled Bedding Transfer for Transmission of Mouse and Rat Infections to Sentinels: A Systematic Review.

PurposeThis systematic review was conducted to gain insight into the efficacy of transmission of infectious agents to colony sentinels by soiled bedding transfer based on publications studying this subject in mice and rats. This information is essential to establish recommendations for the design of health monitoring programs which use sentinels to determine the microbiological status of laboratory animal colonies.ResultsFifteen original articles retrieved from PubMed, Embase, and CAB abstracts met the inclusion criteria. The design of the studies varied substantially per infectious agent with regard to dose of soiled bedding, exposure time, and sentinel strains used.ConclusionWith our conservative criteria for effectiveness, soiled bedding transfer appeared to be effective for MHV, MPV, TMEV, Helicobacter spp., and fur mite infections and ineffective for Sendai virus. For other infectious agents, such as MNV, EDIM, MVM, SDAV, Clostridium piliforme, and pinworms, too few data were available to be able to draw robust conclusions on the efficacy of soiled bedding transfer.RecommendationThe identified evidence only pertains to a portion of the infectious organisms included in the FELASA 2014 guidelines. As many animal facilities design their health monitoring program according to these recommendations, additional studies are warranted to draw comprehensive conclusions on the effective transmission of the infectious agents listed in these guidelines by soiled bedding transfer.