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Enterotoxin excreted by S. aureus is not only well known as a common cause of food poisoning but also as a key factor in contamination of food processing, cooking and storage. An immunological method such as Reverse Passive Latex Agglutination(RPLA) or a genomic molecular method like PCR is widely used to detect enterotoxins from S. aureus. PCR was found to be advantagenous in specificity, sensitivity, speed and cost effectiveness for the serogrouping of enterotoxins from S. aureus. The enterotoxins are immunologically classified as SEA, SEB, SEC, SED and SEE. We randomly collected a total of 1,211 stool specimens and isolated 240(19.8%) strains of S. aureus by the standard culture and identification method. Those 240 isolates of S. aureus were tested for antimicrobial drug susceptibility, and subjected to PCR for the serogrouping of enterotoxins. The enterotoxins were detected from 104(43.3%) isolates, and classified in 4 single groups and 3 mixed groups. They are 38(36.5%), 29(27.9%), 26(25%) and 2(1.9%) strains in single groups of SEA. SED, SEC and SEB, respectively. The mixed groups were 6(5.8%), 2(1.9%). and 1(1.0%) in SEA+SEC, SEB+SED and SEA+SEB, respectively. The distribution of serogroups of 50 enterotoxins detected from S. aureus other than stool specimens were 17(53.1%), 14(43.8%) and 1(3.1%) strains in SEA, SEC and SEA+SEB, respectively, 51(49.0%) strains among 104 enterotoxin producers were classified as methicillin resistant S. oureus(MRSA).
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