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Visceral leishmaniasis (VL) represents a major public health problem in many areas of the world. This review focuses on the impact of periurbanization on the epidemiology and treatment of VL, using Brazil as an example. VL continues to be primarily a disease of poverty with impact on families. However, the disease has expanded in Latin America, with foci reported as far south as Argentina. There is an increasing overlap of Leishmania infantum chagasiand human immune deficiency virus (HIV) infections and other immunosuppressive conditions, resulting in the emergence of VL as an opportunistic infection. This new setting poses new challenges for VL disease control and patient management. Drug Dev Res 72:451–462, 2011. © 2011 Wiley‐Liss, Inc.

We compared HIV-1 subtype B reverse transcriptase (RT) and protease mutation patterns in isolates from heavily treated persons in Northern California with those from persons described in the published literature predominantly from other parts of the United States and Europe. There were few differences in the prevalence of single, double, and triple mutations between the two sets of sequences. More complex patterns of mutations could be characterized by clustering the sequences into eight groups of RT sequences and nine groups of protease sequences according to the presence of known drug-resistance mutations. This clustering accounted for 63% of the variation at RT inhibitor-resistance positions and 68% of the variation at protease inhibitor-resistance positions. The majority of clusters contained Northern California and literature sequences in similar proportions.

Schistosome worms infect over 200 million people worldwide. They live in the host’s bloodstream and alter host immunity.

Leishmania infantum, the causative agent of visceral leishmaniasis (VL) in Brazil, is spread mostly by the bite of the sand fly Lutzomyia longipalpis (Lutz & Neiva). We trapped sand flies in endemic neighborhoods near Natal, Brazil, where cases of human and dog VL were documented. Amplification of species-specific cytochrome b (Cyt b) genes by polymerase chain reaction revealed that sand flies from rural and periurban areas harbored blood from different sources. The most common source of bloodmeal was human, but blood from dog, chicken, and armadillo was also present. We tested the preference for a source of bloodmeal experimentally by feeding L. longipalpis F1 with blood from different animals. There were significant differences between the proportion of flies engorged and number of eggs laid among flies fed on different sources, varying from 8.4 to 19 (P < 0.0001). Blood from guinea pig or horse was best to support sand fly oviposition, but human blood also supported sand fly oviposition well. No sand flies fed on cats, and sand flies feeding on the opossum Monodelphis domestica Wagner produced no eggs. These data support the hypothesis that L. longipalpis is an eclectic feeder, and humans are an important source of blood for this sand fly species in periurban areas of Brazil.