Diarrhea in returning Austrian tourists: epidemiology, etiology, and cost-analyses

Between 1995 and 1997, stool samples of 322 Austrian tourists returning from abroad with diarrhea were examined for bacteria, parasites and viruses.

Epidemiologic data were collected from information furnished by physicians and hospitals and from questionnaires. Moreover, testing expenses and additional cost for treated cases were evaluated.

In 97 of 322 patients examined (30%), one or more pathogens were detected in the stool. Bacteria were found in 38 patients (39%), parasites in 33 patients (34%) and viruses in 26 patients (27%). In 6 patients, mixed infections with parasites and viruses were detected and in 5 patients with bacteria and viruses. Among bacteria, Campylobacter jejuni was most frequent; among parasitic infections, Giardia lamblia. Significant correlations were established between the country of destination, age, travel style and length of stay. Forty-four percent of all patients visited Asia (including Turkey), 27% Africa, 18% Latin America, and only 10% southern Europe. The group between 20 and 29 years of age was most frequently affected (p<.001), the group between 0 and 19 years of age least. Fifty-seven percent stayed in a hotel without frequent changes of location; 43% undertook a trekking trip; and of those, 75% belonged to the group aged between 20 and 39. In terms of the correlation between travel style and pathogen, it was found that 74% of patients with bacterial infections stayed in a hotel (avg. 57.9%; p<.05) whereas 64% of all patients with parasitic infections undertook a trekking trip (avg. 42%; p<.001). Thirty-six percent of all patients with parasitic infections spent their vacation in India (avg. 13%; p<.001). The length of stay of patients with bacterial infections was shorter than average (72% spent between 1 and 2 weeks abroad, avg. 49.8%). Patients with parasitic infections spent significantly more time abroad than average (42% more than 2 months; avg. 17.7%; p<.001). Average cost of specific antimicrobial therapy was U.S.$31 whereas the average cost of identifying a patient needing such treatment was almost U.S.$580.

Optimal detection rate and cost reduction for the diagnosis require precise history, adequate collection of samples using adequate transport media, and rapid transfer to the laboratory.