Virulence Properties and Serotypes of Shiga Toxin-Producing
            <i>Escherichia coli</i>
            from Healthy Australian Cattle

Hornitzky, M.; Vanselow, Barbara; Walker, Kath; Bettelheim, K. A.; Corney, Bruce G.; Gill, P.; Bailey, G. D.; Djordjevic, Steven P.

doi:10.1128/aem.68.12.6439-6445.2002

Cited by 55 publications

(68 citation statements)

References 35 publications

(23 reference statements)

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Only Lira et al (2004) have reported the isolation of STEC strains from mastitic milk, the carriage of stx gene (12.08%) and the distribution of 22.7% (stx 1) and 45.5% (stx 2) genes. This agrees with the results reported in the present study: stx carriage (8.6 %), was distributed between 40.0% (stx 1), and 60.0% (stx 2), with a predominance of stx 2 gene in both studies, in agreement with the results of Hornitzky et al (2002) in Australia, Zschok et al (2000), in Germany, and Irino et al (2005), in Brazil.…”

Section: Discussionsupporting

confidence: 83%

Analysis of Escherichia coli isolated from bovine mastitic milk

Rangel¹,

Marin²

2009

Pesq. Vet. Bras.

View full text Add to dashboard Cite

RESUMO.-[Análise de Escherichia coli isolada de leite de vacas com mastite.]A um longo tempo a mastite tem sido reconhecida como a doença que provoca as maiores perdas econômicas nos rebanhos leiteiros. De fevereiro a novembro de 2004, foram coletadas 670 amostras de leite mastítico de vacas, provenientes de dois estados brasileiros, das quais foram isoladas 231 cepas de Escherichia coli. Estas cepas foram analisadas para a detecção dos genes de produção de Shiga toxina (stx 1 e stx 2) e do gene da intimina (eae). Vinte cepas (8,6%) foram detectadas através de PCR como contendo os genes da Shiga toxina (8 stx 1, 12 stx 2 e nenhuma delas ambos os genes). Duas cepas (0,8%) de E. coli eram eae positivo não produtoras de Shiga toxina. As cepas de E. coli foram também examinadas para detectar a resistên-cia a 12 agentes antimicrobianos. As resistências mais freqüentes foram para tetraciclina (92,2%), estreptomicina (90,4%), ácido nalidixico (88,3%), amicacina (86,5%) e cefalotina (84,8%). A resistência a múltiplas drogas foi encontrada em 152 cepas (65,8%). TERMOS DE INDEXAÇÃO:Escherichia coli, mastite, agentes antimicrobianos, resistência a múltiplas drogas, STEC, gene eae. INTRODUCTIONMastitis remains a major cause of financial loss to the dairy industry and is considered to be economically the most important disease of dairy cattle (Hortet & Seegers 1998 Escherichia coli strains were isolated, were collected from two Brazilian states. The strains were screened for the presence of Shiga toxin-producing (stx 1 and stx 2) and intimin (eae) genes. Twenty (8.6%) strains were detected by PCR to harbor the Shiga toxin genes (8 the stx 1 gene, 12 the stx 2 gene and none both of them). Two (0.8%) of the Escherichia coli strains studied were eae positive non Shiga toxin-producing. The strains were also examined for resistance to 12 antimicrobial agents. The predominantly observed resistance was to tetracycline (92.2%), streptomycin (90.4%), nalidixic acid (88.3%), amikacin (86.5%) and cephalothin (84.8%). Multidrug resistance was found among 152 isolates (65.8%).

show abstract

Section: Discussionsupporting

confidence: 83%

Analysis of Escherichia coli isolated from bovine mastitic milk

Rangel¹,

Marin²

2009

Pesq. Vet. Bras.

View full text Add to dashboard Cite

show abstract

“…EHEC hemolysin, which causes an enterohemolytic phenotype on blood agar, was detected in many STEC strains of different origins (12,13,28,29,69) and was found to be significantly associated with eae-positive STEC strains belonging to classical and emerging EHEC types (13,28,46,69,76). Similar findings were made in our study, where EHEC hemolysin was detected in 96.2% of the eae-positive STEC strains.…”

Section: Discussionsupporting

confidence: 79%

“…By this list, we could identify 41 STEC strains belonging to 31 different serotypes which were not previously described as human STEC (Tables 1 and 2). Some of these "new" O:H types were already reported to be STEC strains from animals, and it was shown that certain STEC serotypes are closely associated with some animal host species (12,26,29,41,53,78,79). Based on these reports, we made an estimate about the possible animal source of the STEC strains from our study.…”

Section: Discussionmentioning

confidence: 93%

“…Protective immunity to intimin may be acquired in early childhood due to infections with eae-positive EPEC and STEC strains (7,21,47), and this may explain why these strains are less frequently isolated from adults. On the other hand, adults are principally more exposed to STEC strains from nonhuman sources due to occupational contact with animals, food, and the environment, and the majority of STEC strains from these sources are negative for intimin (6,20,29,50). This may explain the high frequency of infections with eae-negative STEC strains in adults.…”

Section: Discussionmentioning

confidence: 94%

“…The eae-negative STEC strains were more diverse in their relations to animal hosts. Serotypes O91:[H14], O128:H2, and O146:H21, which represent about 30% of the human eaenegative STEC strains (Table 2), were reported to be associated with sheep (5,12,20,41,78,79), whereas others, such as O22:H8, O113:[H4], and O113:[H21], are common in cattle (29,63). Animal and human STEC strains which belong to the same serotype were found to be similar in their virulence markers, and the transmission of STEC from animals to humans has been reported (86).…”

Section: Discussionmentioning

confidence: 99%

See 2 more Smart Citations

Characterization of Shiga Toxin-Producing Escherichia coli Strains Isolated from Human Patients in Germany over a 3-Year Period

et al. 2004

View full text Add to dashboard Cite

We have investigated 677 Shiga toxin-producing Escherichia coli (STEC) strains from humans to determine their serotypes, virulence genes, and clinical signs in patients. Six different Shiga toxin types (1, 1c, 2, 2c, 2d, and 2e) were distributed in the STEC strains. Intimin (eae) genes were present in 62.6% of the strains and subtyped into intimins ␣1, ␤1, ␥1, , , and . Shiga toxin types 1c and 2d were present only in eae-negative STEC strains, and type 2 was significantly (P < 0.001) more frequent in eae-positive STEC strains. Enterohemorrhagic E. coli hemolysin was associated with 96.2% of the eae-positive strains and with 65.2% of the eae-negative strains. Clinical signs in the patients were abdominal pain (8.7%), nonbloody diarrhea (59.2%), bloody diarrhea (14.3%), and hemolytic-uremic syndrome (HUS) (3.5%), and 14.3% of the patients had no signs of gastrointestinal disease or HUS. Infections with eae-positive STEC were significantly (P < 0.001) more frequent in children under 6 years of age than in other age groups, whereas eae-negative STEC infections dominated in adults. We identified 41 STEC strains belonging to 31 serotypes which had not previously been described as human STEC. Twenty-six of these were positive for intimins ␣1 (one serotype), ␤1 (eight serotypes), (two serotypes), and (three serotypes). Our study indicates that different types of STEC strains predominate in infant and adult patients and that new types of STEC strains are present among human isolates.The association of Shiga (Vero) toxin production in Escherichia coli with human pathogenicity was first described in 1979 (82, 85). However, it was the investigation of an outbreak caused by Shiga toxin-producing E. coli (STEC) O157 which provided the major impetus to study these pathogens (65). In the following years, STEC strains were increasingly isolated from humans with diarrhea and hemolytic-uremic syndrome (HUS) and from farm animals, which serve as a natural reservoir for STEC (52,86). Today, more than 200 different E. coli O:H serotypes are known to be associated with the production of Shiga toxins (86; K. A. Bettelheim's VTEC table, May 2003 update, www.sciencenet.com.au/vtectable.htm). Certain STEC strains belonging to serogroups O26, O103, O111, O145, and O157 were more frequently isolated from humans with severe diseases such as hemorrhagic colitis and HUS. Accordingly, these highly virulent STEC strains were also designated as enterohemorrhagic E. coli (EHEC) (42, 52). The search for additional virulence markers in these pathogens revealed that most EHEC strains carry a plasmid which encodes a hemolysin (EHEC hemolysin) and the chromosomally located locus of enterocyte effacement (LEE) pathogenicity island (16,43,70,84). The genes carried by the LEE enable the bacteria to produce attaching and effacing lesions in the host intestinal mucosa cells, which increases the virulence of the bacteria for humans (35,44,60). Intimate attachment of bacteria to the host cell is mediated by the binding of intimin, the product of the eae gene...

show abstract

Serotypes and virulence genes of ovine non-O157 Shiga toxin-producing Escherichia coli in Switzerland

Zweifel

Blanco

et al. 2004

International Journal of Food Microbiology

View full text Add to dashboard Cite

Virulence Properties and Serotypes of Shiga Toxin-Producing Escherichia coli from Healthy Australian Cattle

Cited by 55 publications

References 35 publications

Analysis of Escherichia coli isolated from bovine mastitic milk

Analysis of Escherichia coli isolated from bovine mastitic milk

Characterization of Shiga Toxin-Producing Escherichia coli Strains Isolated from Human Patients in Germany over a 3-Year Period

Serotypes and virulence genes of ovine non-O157 Shiga toxin-producing Escherichia coli in Switzerland

Contact Info

Product

Resources

About