Detection of virulence genes and the phylogenetic groups of Escherichia coli isolated from dogs in Brazil (original) (raw)
Related papers
Detection of zoonotic diarrheagenic pathotypes of Escherichia coli in healthy household dogs
Iranian Journal of Microbiology
Background and Objectives: Intestinal pathotypes of Escherichia coli belong to the companion animals may poses po- tential risk to public health following zoonotic transmission. Therefore, this study was proposed to determine the virulence genes associated to diarrheagenic E. coli strains isolated from healthy pet dogs and their owners in the southeast of Iran, Kerman province. Materials and Methods: Totally 168 E. coli isolates were collected from 49 healthy household dogs and their owners. Sev- enty isolates were obtained from non-pet owners as control group. Presence or absence of the virulence genes including eae, stx1, stx2, st1, lt1, ipaH, cnf1 and cnf2 were screened by conventional polymerase chain reaction (PCR) and dissemination pattern of the genes were studied among the various hosts. Results: PCR examinations showed that the most frequent virulence gene was ipaH (6.1%) in dogs followed by eae in dog owners (6.1%) and in controls (8.6%). The most frequent pathotypes in do...
Detection of diarrheagenic Escherichia coli strains isolated from dogs and cats in Brazil
Veterinary Microbiology, 2013
Escherichia coli strains can cause several enteric disease and extra-intestinal diseases (Kaper et al., 2004). E. coli is a normal commensal inhabitant of the gut in humans and other warm-blooded animals. Previously, the most extensive investigations of E. coli infection have been described in cattle, sheep, and pigs. However, recently dogs and cats Veterinary Microbiology xxx (2013) xxx-xxx
Veterinary Microbiology, 2002
Twenty-four haemolytic Escherichia coli strains were isolated from dogs with diarrhea. The strains were serotyped and analysed by polymerase chain reaction (PCR) for genes encoding virulence factors associated with E. coli that cause diarrhea in animals. Adhesion antigen production was deduced from haemagglutination experiments. Sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) of heat extracts was also used as an indication for the production of adhesive structures. The majority of the strains was shown to produce this type of virulence factor. Adhesion and invasion tests of the strains and Caco-2 cells showed that all strains adhered and that two were invasive. The two invasive strains were positive in the intimin PCR and one of them also contained genes encoding CS31A. The PCR for heat stable toxin (ST) was positive in only four strains, as was the presence of F17 ®mbrial genes. Surprisingly, 19 strains had intact P ®mbrial operons, coding for an adhesin involved in urinary tract infection (UTI). The cytotoxic necrotising factor 1 (CNF1) gene, also mainly found in UTI was likewise detected in these 19 strains. Cytolethal distending toxin (Cdt) genes were found in ®ve strains. The high number of strains positive for CNF1 and P ®mbriae prompted us to test the strains in a multiplex PCR used to test E. coli isolated from UTI in various species for 30 virulence associated genes. The data showed that the majority of the diarrhea Veterinary Microbiology 85 (2002) 361±377 : S 0 3 7 8 -1 1 3 5 ( 0 2 ) 0 0 0 0 3 -2 isolates have virulence factor pro®les highly similar to UTI E. coli isolates from dogs. This raises the question whether these isolates are real intestinal pathogens or``innocent bystanders''. However, since CNF1 producing necrotoxic E. coli (NTEC) strains isolated from humans, pigs and calves with diarrhea appear to be highly related to our strains, it might be that in dogs this type of isolate is capable of causing not only UTI, but also diarrhea. If this is the case and this type of isolate is`b ifunctional'', domestic animals likely constitute a reservoir of NTEC strains which can be also pathogenic for humans. #
Indian Journal of Animal Research, 2015
Diarrhoea in canines is mainly caused by Escherichia coli which can be fatal also. To understand the depth of this infection, a study was undertaken to detect E. coli isolates from diarrhoeic and non-diarrhoeic dogs in Southern part of West Bengal. A total of 112 canine samples were tested during May to September 2012 revealing approx 63.4% (71) samples positive for Escherichia coli. The most common serotypes were O8 (23.9%) followed by O157 (19.7%), O101 (16.9%), O26 (15.5%), O153 (12.7%) and O6 (11.3%). Among these O6, O8, O26 and O157 were highly pathogenic to mice causing almost 100% mortality within 24hrs of inoculation and were also detected to be haemolytic on sheep blood agar plates except serotype O8. These isolates were mostly sensitive to nalidixic acid (80.29%), cotrimoxazole (78.88%), ciprofloxacin (74.65%), colistin and ceftriaxone (both 71.83%) but were resistant to amikacin (97.18%), kanamycin (95.78%), cephalexin (92.96%) and enrofloxacin (84.51%).
Comparative Clinical Pathology, 2011
Animal contacts have been regarded as an emerging rout of Shiga toxin-producing Escherichia coli (STEC) infection in humans. Diarrhoeic and asymptomatic dogs have been recognised as a reservoir of atypical enteropathogenic Escherichia coli (EPEC), and STEC in some investigations. In this study E. coli isolates from 100 faecal samples of healthy (n=50) and diarrhoeic (n=50) dogs were screened by polymerase chain reaction (PCR) for the presence of determining virulence genes of STEC and EPEC pathotypes including stx and eaeA. The confirmed virulence-positive strains were subjected to antimicrobial susceptibility testing against 12 antibacterial using disc diffusion method. Resistance profiles were also determined for the STEC and EPEC strains. Ten isolates from 10 dogs (10%) were shown to possess at least one of the tested virulence genes. Six of these isolates (6%) harboured only the eaeA gene and were considered as EPEC. Four isolates (4%) were stx+ and regarded as STEC, of which two were stx+/eae+. The resistance was specially observed against penicillin, ampicillin, sulfomethoxazole, streptomycin and oxytetracyclin. Altogether, nine resistance profiles were observed among 10 isolates. In conclusion, dogs can act as a reservoir for EPEC and STEC strains, and close contacts of children with companion animals can be a potential risk factor in development of diarrhoea and haemolytic uremic syndrome. In rural areas shepherd dogs can also be a transient carrier of STEC strains that they may acquire from ruminants. To our knowledge this is the first study which reports the faecal shedding of STEC and EPEC from dogs in Iran.
Animal health research reviews / Conference of Research Workers in Animal Diseases, 2001
The pathogenic strains of Escherichia coli recovered from the intestinal tract of animals fall into categories called enterotoxigenic, enteropathogenic, enterohemorrhagic and necrotoxigenic. The other two categories, enteroinvasive and enteroaggregative, have not been reported in animals. The pathogenicity of these strains is determined by the presence of certain genes that encode adhesins and toxins, are generally organized in large blocks in chromosomes, large plasmids or phages, and are often transmitted horizontally between strains. In this review, we summarize current knowledge of the virulence attributes that determine the pathogenic potential of E. coli strains and the methods available to assess the virulence of the strains. We also discuss the clinical symptoms, the gross and histological lesions, and the molecular diagnostic methods our laboratories have implemented for detecting pathogenic strains of E. coli that are isolated from the gastrointestinal tract of animals.
Journal of Water and Health, 2011
The aim of this work was to verify the presence of seven virulence factors (ST, LT, eae, stx 1 , stx 2 , INV and EAEC) among Escherichia coli strains isolated from healthy humans, bovines, chickens, sheep, pigs and goats, from two sewage treatment plants and from the Tietê River. We have found a high prevalence of eae, stx 1 and stx 2 in ruminants. The EAEC gene was only found in humans and sewage. No strains presented ST, LT or INV. BOX-PCR fingerprints revealed a high diversity among the strains analysed and a non-clonal origin of strains that presented the same virulence factors. Therefore, we concluded that ruminants may constitute an important reservoir of most diarrheagenic E. coli in Brazil, except for EAEC strains. These results emphasize the importance of the identification of the animal source of fecal contamination for the correct water risk assessment.
Comparative Immunology, Microbiology and Infectious Diseases, 2012
In this study, fecal Escherichia coli isolates (n = 188) from 34 dog-owner pairs and 26 healthy control humans (2 isolates per individual) were tested for susceptibility to 6 antimicrobials and screened for virulence genes. Genetic diversity between canine and owner isolates was evaluated by pulsed-field gel electrophoresis (PFGE). Canine isolates exhibited significantly different rates of resistance to four and two antimicrobials, compared to control and owner isolates, respectively. Of the genes examined, the prevalence of sfa, hly, and cnf genes in canine isolates were higher than in control isolates, but not than in owner isolates. These results suggest that characteristics of owner isolates are somewhat similar to canine isolates, compared to isolates from non-dog owners. In addition, PFGE analysis revealed that transfer of E. coli between owners and their dogs had occurred within 3/34 (8.8%) households. Considering the effects of dog ownership on the population of E. coli isolates from owners, further epidemiological studies are required.