Evidence that domestic dogs may act as reservoir hosts for cutaneous leishm
aniasis in the Peruvian Andes is provided by the isolation, for the first t
ime, from naturally infected dogs of parasites identified (by isoenzymes) a
s Leishmania peruviana. Leishmania parasites were isolated from nasal aspir
ates or biopsies from 5 (1.8%) of 279 asymptomatic dogs sampled in endemic
villages of the Peruvian Andes. In addition, Leishmania ( Viannia) infectio
ns were identified in 15 (5.4%) of 276 nasal samples by the polymerase chai
n reaction (PCR) using subgenus-specific primers. Further circumstantial ev
idence for a reservoir role for dogs comes from the finding of a relatively
high dog blood index among the sandfly vectors collected inside houses (29
% for Lutzomyia peruensis and 17% for Lu. verrucarum). Possible wild mammal
reservoir hosts for Andean cutaneous leishmaniasis were also detected in e
ndemic villages. At least 8 species were identified among the 1266 small ma
mmals trapped. Leishmania parasites were isolated from blood or skin biopsi
es taken from 2 (2.6%) of 78 Didelphis albiventris and 6 (1.2%) of 511 Phyl
lotis andinum. Three isolates were identified by isoenzymes as L. peruviana
, and the other 5 were identified by PCR as Leishmania (Viannia) species. L
eishmania (Viannia) infections were also identified by PCR directly on skin
biopsies taken from 2 (2.8%) of 72 D. albiventris, 1 (0.2%) of 499 P. andi
num, and 4 (2.6%) of 153 Akodon sp.