Authors

L MeursA M PoldermanN Vinkeles Melchers-MartinezE BrienenJ J VerweijB GroosjohanF MendesM MechenduraD H HeppM LangenbergR EdelenboschK PolmanL van Lieshout ¹ Catholic University of Mozambique, Mozambique;  ² Institute of Tropical Medicine, Belgium;  ³ Leiden University Medical Center, Netherlands

Discussion

Intestinal parasites are common in low income countries. However, accurate prevalence data are scarce due to diagnostic restraints. The present study investigated the diagnostic accuracy of five classical microscopy techniques for the detection of a broad spectrum of intestinal parasites in a cross-sectional population-based survey performed in a poor suburb of Beira, Mozambique. One stool sample per participant (n=303) was examined by direct smear, formal-ether concentration (FEC), Kato smear, Baermann and coproculture. Real-time PCR for the detection of DNA of five helminth and five protozoa species was used for comparison. We found that virtually all people harboured at least one parasite (98%), and that 66% harboured 3 or more. Among the microscopic techniques, FEC was able to detect the broadest spectrum of species. However, FEC also missed a considerable number of infections, notably Strongyloides stercoralis, Schistosoma mansoni and Giardia lamblia. PCR outperformed microscopy in terms of sensitivity and range of parasite species detected. The disadvantage of PCR, however, is that it is generally not feasible in poor resource settings, at least not in peripheral labs. Thus, until a more field-friendly approach becomes available, (a combination of) microscopic techniques remain(s) the best available option for local, on-the-spot diagnosis.