Diarrhoea in a large prospective cohort of European travellers to resource-limited destinations.
BACKGROUND
Incidence rates of travellers' diarrhoea (TD) need to be updated and risk factors are insufficiently known.


METHODS
Between July 2006 and January 2008 adult customers of our Centre for Travel Health travelling to a resource-limited country for the duration of 1 to 8 weeks were invited to participate in a prospective cohort study. They received one questionnaire pre-travel and a second one immediately post-travel. First two-week incidence rates were calculated for TD episodes and a risk assessment was made including demographic and travel-related variables, medical history and behavioural factors.


RESULTS
Among the 3100 persons recruited, 2800 could be investigated, resulting in a participation rate of 89.2%. The first two-weeks incidence for classic TD was 26.2% (95%CI 24.5-27.8). The highest rates were found for Central Africa (29.6%, 95% CI 12.4-46.8), the Indian subcontinent (26.3%, 95%CI 2.3-30.2) and West Africa (21.5%, 95%CI 14.9-28.1). Median TD duration was 2 days (range 1-90). The majority treated TD with loperamide (57.6%), while a small proportion used probiotics (23.0%) and antibiotics (6.8%). Multiple logistic regression analysis on any TD to determine risk factors showed that a resolved diarrhoeal episode experienced in the 4 months pre-travel (OR 2.03, 95%CI 1.59-2.54), antidepressive comedication (OR 2.11, 95%CI 1.17-3.80), allergic asthma (OR 1.67, 95%CI 1.10-2.54), and reporting TD-independent fever (OR 6.56, 95%CI 3.06-14.04) were the most prominent risk factors of TD.


CONCLUSIONS
TD remains a frequent travel disease, but there is a decreasing trend in the incidence rate. Patients with a history of allergic asthma, pre-travel diarrhoea, or of TD-independent fever were more likely to develop TD while abroad.
Pitzurra
Raffaela
R
University of Zurich, Institute for Social and Preventive Medicine, Division of Epidemiology and Prevention of Communicable Diseases and World Health Organization Collaborating Centre for Travellers' Health, Zurich, Switzerland. pitzurra@ifspm.uzh.ch
Steffen
Robert
R
Tschopp
Alois
A
Mutsch
Margot
M
D000293:Adolescent; D000328:Adult; D000350:Africa, Central; D000354:Africa, Western; D000368:Aged; D000930:Antidiarrheals / Q000627:therapeutic use; D015331:Cohort Studies; D003906:Developing Countries; D003967:Diarrhea / Q000188:drug therapy / Q000453:epidemiology*; D005060:Europe / Q000453:epidemiology; D005260:Female; D006801:Humans; D015994:Incidence; D007194:India; D008139:Loperamide / Q000627:therapeutic use; D008297:Male; D008875:Middle Aged; D019936:Probiotics / Q000627:therapeutic use; D011446:Prospective Studies; D012307:Risk Factors; D011795:Surveys and Questionnaires; D014195:Travel; D055815:Young Adult
D000930:Antidiarrheals; D008139:Loperamide