Methods: 1297 foreign-born adults (≥18 years), living ≤5 years in Canada, were recruited between October 2002 and December 2004. Socio-demographic information was collected via a questionnaire. Antibodies to recombinant Strongyloides stercoralis NIE antigen [Optical density (OD) <0.30=negative, ≥ 0.30=positive] and Schistosoma mansoni [OD <0.40=negative, ≥ 0.40=positive] were detected by ELISA on stored, banked sera.
Results: The mean age was 32.4 ± 8.8 years, 66% were female, and 44% were refugees. Overall 31.3% [95% CI: 29-34%] had antibodies to strongyloides and ranged from 22-45% in 6 different geographic regions. In multivariate analysis, after adjusting for age, sex, region of origin, and several socioeconomic factors, positive strongyloides serology was more common in men [OR 1.4, 95% CI: 1.1-1.8] and in refugees compared to immigrants [OR 1.4, 95% CI: 1.01-2.0]. Although refugees were more likely to be seropositive for strongyloides [36.7%, 95% CI: 33-40%], a total of 26% (95% CI: 23-29%) of immigrants also had positive serology. Overall 7.4% had schistosoma antibodies and those from Sub-Saharan Africa were the most likely to be seropositive [19.9%, 95% CI 4-26%]. In multivariate analysis, the only significant predictor of positive schistosoma serology was originating from Sub-Saharan Africa [OR 6.1, 95%CI: 2.9-12.7].
Conclusion: A large proportion of both immigrants and refugees from all world regions are infected with strongyloides. Migrants from Sub-Saharan Africa are at greatest risk for schistosoma. Both immigrants and refugees are at risk for these diseases and may benefit from targeted screening programs and or empiric treatment.
B. Ward, None
S. Cnossen, None
M. Libman, None
C. Greenaway, None