Incidence and clinical symptoms of Aeromonas-associated
travellers' diarrhoea in Tokyo
|S. YAMADA a1, S. MATSUSHITA a2, S. DEJSIRILERT a3 and Y. KUDOH a4|
a1 Tama Branch Laboratory,
Tokyo Metropolitan Research Laboratory of Public Health,
3-16-25, Shibazaki-cho, Tachikawa, Tokyo 190, Japan
a2 Department of Microbiology,
Tokyo Metropolitan Research Laboratory of Public Health, Tokyo,
a3 Division of Clinical Pathology, Department of Medical
Science, Nonthaburi, Thailand
a4 School of Health Science, Kyorin University,
In a survey examining the causes of travellers' diarrhoea
treated in Tokyo between July 1986
and December 1995, Aeromonas species were isolated from 1265
(5·5%) of 23215 travellers
returning from developing countries. Aeromonas species were the
fourth most frequent
enteropathogen isolated, following enterotoxigenic E.
(8·5%), Salmonella spp. (7·6%) and
shigelloides (5·6%). Aeromonas
species were found in 1191 (5·6%) of 21257
patients with diarrhoea and in 74 (3·8%) of 1958 healthy
individuals without diarrhoea. Mixed
infection was observed in 512 (40·5%) cases. No significant
difference in the prevalence of
Aeromonas by year, season, age distributions, or sex was observed,
but a slight difference was
noted depending on the country where the travellers visited. Of the 1265
893 strains (70·6%) were A.
veronii biovar sobria, 330
(26·1%) were A.
hydrophila, and 42
(3·3%) were A.
caviae. The clinical symptoms of patients
whom Aeromonas species was
isolated as the only potential enteric pathogen were almost similar, which
diarrhoea (about 60%), abdominal cramps (43%), fever (around 15%), and
vomiting (13%). Although the severity of illness was milder than that of
alone, these data suggest that Aeromonas species are important
enteric pathogens in travellers' diarrhoea.
(Accepted April 10 1997)