Numerical taxonomy of some Old World Leishmania species.

Iraqi Leishmania stocks originating from human cutaneous and visceral infections, others from the sandfly Sergentomyia baghdadis, and one visceral stock from a dog, were compared among themselves and with Old World reference stocks, by electrophoresis of 11 enzymes. 79 unit characters emerged. Paired comparison technique and complete-linkage cluster analysis revealed heterogeneity within the L. donovani complex. The Iraqi L. donovani stocks appear to be more closely related to an Ethiopian reference L. donovani than to an L. donovani infantum. Two Indian visceral stocks were linked to the L. donovani complex and the L. tropica complex by similarity indices of the same range. The results show a marginally closer association between L. tropica and L. donovani complexes than between L. tropica and L. major.