Molecular identification ofEntamoebaspecies in savanna woodland chimpanzees (Pan troglodytes schweinfurthii)

SUMMARYTo address the molecular diversity and occurrence of pathogenic species of the genusEntamoebaspp. in wild non-human primates (NHP) we conducted molecular-phylogenetic analyses onEntamoebafrom wild chimpanzees living in the Issa Valley, Tanzania. We compared the sensitivity of molecular [using a genus-specific polymerase chain reaction (PCR)] and coproscopic detection (merthiolate-iodine-formaldehyde concentration) ofEntamoebaspp. We identifiedEntamoebaspp. in 72 chimpanzee fecal samples (79%) subjected to species-specific PCRs for sixEntamoebaspecies/groups (Entamoeba histolytica, Entamoeba nuttalli, Entamoeba dispar, Entamoeba moshkovskii, Entamoeba coliandEntamoeba poleckiST2). We recorded threeEntamoebaspecies:E. coli(47%),E. dispar(16%),Entamoeba hartmanni(51%). Coproscopically, we could only distinguish the cysts of complexE. histolytica/dispar/moshkovskii/nuttalliandE. coli. Molecular prevalence of entamoebas was higher than the prevalence based on the coproscopic examination. Our molecular phylogenies showed that sequences ofE. disparandE. colifrom Issa chimpanzees are closely related to sequences from humans and other NHP from GenBank. The results showed that wild chimpanzees harbourEntamoebaspecies similar to those occurring in humans; however, no pathogenic species were detected. Molecular-phylogenetic methods are critical to improve diagnostics of entamoebas in wild NHP and for determining an accurate prevalence ofEntamoebaspecies.