Leishmaniasis vector potential of Lutzomyia spp. in Colombian coffee plantations.

Potential vectors of Leishmania braziliensis Vianna were assessed at four study sites in the mountainous Valle del Cauca, western Colombia, from March to June 1989. In an active focus of transmission at 1450 m altitude, a coffee plantation at Versalles, there were high densities of antropophilic phlebotomines: Lutzomyia columbiana (Ritorcelli & Van Ty) and Lu.townsendi (Ortiz), both in the verrucarum species group, and of Lu.pia (Fairchild & Hertig). At a comparable altitude in a forest reserve at Yotoco where leishmaniasis is unknown, Lu.pia was the prevalent species and Lu.townsendi was absent. In two localities at 1150 m altitude, there were plentiful Lu.lichyi (Floch & Abonnenc) plus both species in the verrucarum group, but Lu.pia was absent. One of these localities, a coffee plantation at Villa Hermosa where a leishmaniasis outbreak occurred in 1986, was compared with a leishmaniasis-free, partly wooded nature reserve at Mateguadua. No natural infections of Leishmania were found in a total of 1896 wild-caught female phlebotomines belonging to at least seven species. It remains unclear why Leishmaniasis transmission is associated with coffee plantations in this part of Colombia. Laboratory-bred Lu.lichyi females were invariably autogenous, and blood-seeking females of this species were always parous. Parity rates in wild-caught females of other species were 55% Lu.pia, 24% Lu.columbiana and 14% Lu.townsendi. Female Lutzomyia infected artificially with Le.braziliensis promastigotes developed peripylarian infections. Higher proportions of Lu.townsendi (96%) and Lu.columbiana (78%) became infected but these species developed lower rates of stomodaeal infections (P less than 0.1) than Lu.lichyi (37%) or Lu.pia (44%).(ABSTRACT TRUNCATED AT 250 WORDS)

Localized cutaneous leishmaniasis (chiclero's ulcer) in Mexico: sensitivity and specificity of ELISA for IgG antibodies to Leishmania mexicana mexicana.

Sera from 223 human beings were assayed by enzyme-linked immunosorbent assay for immunoglobulin G antibodies to Leishmania mexicana mexicana promastigotes. 76% of 74 sera from patients with chiclero's ulcer gave positive reactions at a titre of 1:40; the positivity rate was lower in patients with long-standing infections. False positive reactions were obtained with only 7% of 56 sera from healthy individuals with positive Montenegro tests and with 6 of 7 sera from patients with Chagas disease. It is concluded that this method would be a useful contributory diagnostic method in cases of suspected chiclero's ulcer.

Estudio preliminar de correlacion clinica, histopatologica e inmunologica de la leishmaniasis cutanea mexicana en el hombre. / Preliminary study of clinical, histopathological and immunological correlation of Mexican cutaneous leishmaniasis in the man

Se estudiaron un total de siete pacientes provenientes de area endemica y con cuadro clinico de leishmaniasis cutanea mexicana.Se les practicaron historia clinioepidemiologica, biopsia, evaluacion de perfil inmunologico (linfocitos T y B, determinacion de inmunoglobulinas y C3) y reaccion inmunitaria especifica (intradermorreaccion de Montenegro y ELISA). Clinicamente no se encontraron diferencias con lo informado en la literatura. El patron histopatologico es caracteristico y diferente a lo encontrado en otras leishmaniasis cutaneas. Inmunologicamente los hallazgos sobresalientes fueron hipergammaglobulinemia en 6/7 (85.71 por ciento) y ELISA positivo en 5/7 (71.42 por ciento). Se discuten las posibles correlaciones y se proponen criterios diagnosticos