ABSTRACT
Dogs are considered the main
reservoir of
Leishmania infantum. This protozoan causes
visceral leishmaniasis (VL), an uncontrolled urban zoonosis in
Brazil.
Serological tests and
polymerase chain reaction (
PCR) on peripheral
blood were performed to identify infected
dogs in scenarios of higher and lower
prevalence of the
disease (Teresina and Vitória). One-hundred infected and 57 non-infected
animals from Teresina and 100 non-infected
animals from Vitória were studied.
Animal selection was not dependent on previous
serology. The
sensitivity (Teresina) and
specificity (Teresina and Vitória) were as follows indirect antibody
fluorescence (IFAT) cut-off of 140 (IFAT 140) 96%, 18%, and 76%; IFAT 180 90%, 33%, and 93%; direct
agglutination test (DAT) 96%, 33%, and 98%; fast
agglutination screening test (FAST) 93%, 68%, and 100%;
immunochromatographic assay with a recombinant rK39
antigen (rK39) 88%, 74%, and 98%;
enzyme linked immunosorbent assay (
ELISA) 91%, 79%, and 98%; rapid dual-path platform test (TR DPP®) 98%, 60%, and 98%; and
blood PCR 29%, 93%, and 97%, respectively. In the high
transmission area, none of the tests adequately discriminated L. infantum-infected from non-infected
dogs. However, in the high
transmission city, the area under the
receiver operating characteristic (ROC) curve of FAST, DAT, ICrK39,
ELISA and TR DPP® was high.