The Use of Real-time PCR to Identify Entamoeba Histolytica and E-dispar Infections in Prisoners and Primary-school Children in Ethiopia.

Abstract

In Ethiopia, it is generally unknown what proportion of the amoebic infections commonly found, by microscopy, in humans are caused by non-invasive Entamoeba dispar rather than the potentially invasive E. histolytica. Faecal samples were therefore collected from 363 primary-school students and 409 prisoners from various regions of Ethiopia. Each of these samples was checked for Entamoeba infection by the microscopical examination of formol–ether concentrates. DNA was then extracted from the 213 samples (27.6%) found Entamoeba-positive, and run in a real-time PCR with primers, based on the SSU-rRNA gene sequences of E. histolytica and E. dispar, that allow DNA from the two species to be distinguished. Although E. dispar DNA was identi ed in 195 (91.5%) of the 213 samples checked by PCR, no E. histolytica DNA was detected. This nding is consistent with the conclusion of a previous, smaller investigation: that many amoebic infections in Ethiopia are incorrectly attributed to E. histolytica and then treated, unnecessarily, with amoebicidal drugs.