title: Determination of verocytotoxin and eae gene loci by multiplex PCR in Escherichia coli O157:H7 isolated from human faeces in Northern Ireland: a four-year study of trends, 1997-2000.
abstract: This study aims to determine the distribution and frequency of verocytotoxin genes in human faecal clinical isolates of Escherichia coli O157 in Northern Ireland during the period 1997-2000, using a special four-target multiplex polymerase chain reaction (PCR) assay. One hundred and thirty two isolates of E. coli O157:H7 cultured during the four-year period (1997 [n=28]; 1998 [n=25]); 1999 (n=43); 2000 [n=36]), representing approximately 79% of total E. coli O157 laboratory isolations throughout N. Ireland, are examined for the presence of verocytotoxin gene loci (VT1, VT2 and eae) using a multiplex PCR assay. These isolates originate from the four Regional Area Health Boards that constitute the healthcare system in N. Ireland as follows: Eastern (53.8%; n=71), Northern (34.1%; n=45), Western (6.8%; n=9) and Southern (5.3%; n=7). Results showed that over 80% of these isolates possessed the VT2 and eae gene loci, with the remainder being predominantly VT1-, VT2- and eae-positive. None possessed the VT1 gene locus alone. Development and adoption of this simple four-target (three virulence and one control gene loci) multiplex PCR assay and subsequent recording of resulting verocytotoxin-typing data in a database, permitted local, rapid determination of carriage of known molecular virulence determinants of E. coli O157 isolates, which may aid in outbreak-related epidemiological investigations or other longitudinal studies.
authors.affiliation: Northern Ireland Public Health Laboratory, Department of Bacteriology, Belfast City Hospital, Belfast BT9 7AD, UK.
authors.forename: J L D
authors.initials: JL
authors.lastname: Crothers
authors.forename: J E
authors.initials: JE
authors.lastname: Moore
authors.forename: B C
authors.initials: BC
authors.lastname: Millar
authors.forename: M
authors.initials: M
authors.lastname: Watabe
authors.forename: P J
authors.initials: PJ
authors.lastname: Rooney
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D015373:Bacterial Typing Techniques; D002648:Child; D002675:Child, Preschool; D004927:Escherichia coli Infections / Q000382:microbiology; D019453:Escherichia coli O157 / Q000145:classification* / Q000235:genetics; D005243:Feces / Q000382:microbiology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D016133:Polymerase Chain Reaction / Q000379:methods; D022603:Shiga Toxins / Q000032:analysis / Q000235:genetics*
chemical_list: D022603:Shiga Toxins