Schistosome infection among river rafters on Omo River, Ethiopia.
BACKGROUND
Adventure trips to Africa have become more frequent, and rafting on some of the great rivers has become almost commonplace. We describe three rafting trips on the Omo River in Ethiopia, after which most of the participants were diagnosed with schistosomiasis.


METHODS
After index cases from the three groups came to medical attention, active surveillance detected outbreaks of illness in a group of American travelers (n = 18 ) in 1993 and in two groups of Israeli travelers in 1997 (n = 26).


RESULTS
Of 44 travelers, 37 were screened and 28 (76%) were infected, all with Schistosoma mansoni. Among the infected patients, 16 of 28 (57%) were symptomatic, the most frequent manifestation being fever, which occurred in 14 of 25 (56%); cough occurred in 6 of 18 (33%). Diagnosis was based on FAST-enzyme-linked immunosorbent assay, with confirmation by immunoblot. Other rafting trips on the Omo River sponsored by the same tour companies did not result in symptomatic infection. Investigation of the rafting itineraries suggested the route may have been altered from the usual for these three groups, exposing them to a part of the river that is wider, slower moving, and more densely populated.


CONCLUSIONS
Schistosomiasis should be considered in febrile patients following rafting trips in schistosome-endemic areas. As asymptomatic schistosomiasis in travelers is also common (43% in this series), all travelers exposed to freshwater in endemic areas should be encouraged to undergo serologic screening.
The Center for Geographic Medicine, Department of Medicine C, The Chaim Sheba Medical Center, Tel Hashomer, Israel.
Eli
E
Schwartz
Phyllis
P
Kozarsky
Marianna
M
Wilson
Martin
M
Cetron
D000208:Acute Disease; D000328:Adult; D003371:Cough / Q000469:parasitology; D004196:Disease Outbreaks / Q000706:statistics & numerical data*; D004797:Enzyme-Linked Immunosorbent Assay; D005002:Ethiopia; D005334:Fever / Q000469:parasitology; D006801:Humans; D007557:Israel / Q000453:epidemiology; D011322:Primary Prevention / Q000458:organization & administration; D012307:Risk Factors; D045483:Rivers; D012552:Schistosomiasis / Q000175:diagnosis* / Q000188:drug therapy / Q000453:epidemiology / Q000276:immunology; D012556:Schistosomicides / Q000627:therapeutic use; D016036:Seroepidemiologic Studies; D014195:Travel; D014481:United States / Q000453:epidemiology
D012556:Schistosomicides