Genetic Diversity and Ancestral Relationship between LEE-negative and LEE-positive STEC
The 871-bp amplicon of repA was sequenced for 16 LEE-negative and 13 LEE-positive STEC strains.
But in 2011, most of the existing techniques for detecting STEC were not commercially available.
USDA-ARS scientists have developed an analytical technique that screens for all six non-O157 STEC groups.
Thanks to the collaboration of FSIS and ARS, and a prompt response from ERRC scientists, a fast, effective detection method for identifying the top six non-O157 STECs on meat samples is available for food safety efforts that help protect consumers.--By Rosalie Marion Bliss, ARS.
Shiga-toxin-producing Escherichia coli (STEC) serogroup 0157:H7 has long been associated with severe forms of foodborne illnesses.
For example, public health surveillance for STEC has traditionally focused on E.
Virtually everything we know about disease and the epidemiology of enteric pathogens, such as Salmonella spp., Shiga toxin-producing Escherichia coli (STEC), e.g., O157, and Campylobacter spp., has been generated from the study of patients with culture-confirmed infections.
In India, there is a paucity of information on STEC. It has not been identified as an etiologic agent of diarrhea in India.
Serotyping of STEC alone is insufficient to assess the pathogenic properties of the strains because such organisms are quite variable in their repertoire of virulence determinants.
Escherichia coli O157:H7 EDL933 Sor-/[beta]glu-/E-Hly+/eae+, biotype C, producer of Stx1 and Stx2, was employed as positive control in PCR targeting STEC
stx1/stx2 genes and Salmonella Braenderup H9812 was used as molecular size marker in PFGE.
Although the most common serogroups of STEC
in Europe and the USA are E.coli 0157 or 026, the incidence of other serotypes is increasing.