Article

Molecular analysis of enterohemorrhagic Escherichia coli isolates in Japan and its application to epidemiological investigation.

Department of Bacteriology, National Institute of Infectious Diseases, Tokyo, Japan.
Pediatrics International (impact factor: 0.63). 05/1999; 41(2):202-8. pp.202-8
Source: PubMed

ABSTRACT Many outbreaks of enterohemorrhagic Escherichia coli (EHEC) O157 infections occurred in Japan in 1996. Molecular epidemiological analyses of the isolates by methods such as XbaI-digested, pulsed-field gel electrophoresis (PFGE), revealed that a variety of PFGE type strains have spread all over Japan. They also showed that such molecular methods are very useful for confirming the epidemiologically related isolates and in assisting the epidemiological investigation. Recent characteristic features of the infection are that the incidence of patients experiencing symptoms such as abdominal cramps, diarrhea and hemorrhagic colitis is higher in children younger than 9 years old; however, that of asymptomatic carriers seems to be higher in adults; and that EHEC O157:H7-serotyped strains are still the main isolates, while the isolation frequency of other serotype strains, such as O26 and O111, is increasing.

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Keywords

9 years old
 
children younger
 
diarrhea
 
enterohemorrhagic Escherichia coli
 
hemorrhagic colitis
 
Japan
 
Molecular epidemiological analyses
 
molecular methods
 
outbreaks
 
patients
 
pulsed-field gel electrophoresis
 
Recent characteristic features
 
serotype strains
 
XbaI-digested
 

H Watanabe