The taxonomic attribution of four Leishmania stocks isolated from humans in Ecuador has been explored by both multilocus enzyme electrophoresis and random amplified polymorphic DNA. For three loci, MLEE results showed patterns suggesting a heterozygous state for a diploid organism, while the corresponding homozygous states are characteristic of the Leishmania panamensis/guyanensis complex and Leishmania braziliensis, respectively. Other enzyme loci showed characters attributable to either the L. panamensis/ guyanensis complex or L. braziliensis. RAPD profiles exhibited for several primers a combination of the Leishmania panamensis/ guyanensis complex and L. braziliensis characters. These data hence suggest that the four stocks are the result of hybridization between L. panamensis/guyanensis and L. braziliensis. MLEE data show that the results cannot be attributed to either mixture of stocks, or an F1 in the framework of a simple Mendelian inheritance.

Male Lutzomyia longipalpis of two types from Bolivia were compared using isozyme electrophoresis and wing morphometry. One sample (ex Chiflonkaka Cave, alt. 2800 m at Toro Toro, Charcas Province, Potosi Department) was 'two-spot' phenotype males (i.e. tergites III and IV with paired pale patches of pheromone glands), whereas two other locality samples (Apa Apa and Imanaco, Sud Yungas Province, La Paz Department) were one-spot male phenotype (only tergite IV with paired pale patches). Multilocus enzyme electrophoresis (using ACON, aGPD, GPI, IDH, MDH, ME, 6PGD, PGM, LAP and PEPB) found no difference between samples from adjacent hen houses at Apa Apa. Nei's standard genetic distance between one-spot samples from Apa Apa and Imanaco (5 km apart, 1500 m alt.) was 0.001-0.002, whereas the two-spot males from Toro Toro (800 km away) showed a genetic distance of 0.081 from the one-spot males (Apa Apa and Imanaco). This genetic distance is commensurate with speciation, but may simply be intraspecific differentiation due to 'isolation by distance'. For comparative wing morphometry, we included additional material of one-spot males from Bolivia (Guyabal, Sud Yungas, La Paz), Brazil, Colombia and Nicaragua. These three other country samples were assumed to be different sibling species in the complex Lutzomyia longipalpis (Lanzaro et al., 1993). Statistics were based on univariate and multivariate analysis. The comparison between size-in and size-free canonical variate analysis (CVA) indicated that the wing morphometric divergence between one-spot and two-spot Bolivian phenotypes was not size dependent and could have taxonomic significance.

Abstract. In the course of an epidemiologic survey in Ecuador, the following collection of Leishmania stocks was isolated: 28 from patients with clinical signs of leishmaniasis, 2 from sloths, 1 from a dog, and 4 from sand flies. For genetic characterization of these stocks, multilocus enzyme electrophoresis (MLEE) and random amplified polymorphic DNA (RAPD) were used. Twenty six of the 35 stocks were identified as either Leishmania (V.) panamensis or L. Cutaneous and mucocutaneous leishmaniases constitute a serious public health problem in Ecuador, since the disease is endemic in 17 of 20 provinces.1 The most frequent clinical forms are the cutaneous and mucocutaneous ones, with a large spectrum of clinical variation. 2 This clinical variability of the disease is believed to be due to the Leishmania species diversity encountered in Ecuador.1 Seven Leishmania species are known to be responsible for infections reported in the country: 7 These two species belong to the guyanensis complex according to the World Health organization classification. 8 Genetic and biochemical analysis demonstrated that they are genetically very close and that only one enzymatic system could be used as a diagnostic marker able to discriminate them. 9 This study reports the genetic analysis of 35 Leishmania isolates collected in the course of extensive field studies in Ecuador. 10 This genetic epidemiology study improves our knowledge on the epidemiology of the disease in this country. Moreover, the results clearly raise the question of the distinctness between L. (V.) panamensis and L. (V.) guyanensis.

Parasites belonging to

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Human bartonellosis is found predominantly in Perú2, 6, 8, 12, 15, as well as in Ecuador3, 7, 10 and Colombia13, 15. In Peru, the disease is restricted to the valleys of the western-side and a few inter-andean and eastern-slopes of the andean valleys6, 15, 18 at altitudes between 1000 and 3200 masl. Most human cases are reported from the regions of Chavin, Nor Oriental del Marañon and Lima16. Lutzomyia verrucarum is presumed to be the only vector of human bartonellosis in the valleys of Peru1, 2, 8, 11, 17, 19/ Our research objetive was to detect the presence of Lu. verrucarum in various localities known to be endemic for human bartonellosis in three provinces of Region Nor Oriental del Marañon. Sandfly collections were made between 1987 and 1992 during four visits to bartonellosis-endemic provinces: San Ignacio (districts of San José de Lourdes: 1020-1260 m and La Coipa: 1200-1560 m), Jaén (districts of Santa Rosa: 1300-1680 m and Jaén: 1220-1680 m) and Utcubamba (districts of Lonya Grande: 1200 m and El Milagro: 1200-1540 m

Eleven enzyme systems were used to compare 2 cryptic species previously treated as PsycRodopygus carrerai. Two enzyme systems were each completely diagnostic. Three other loci gave evidence of reproductive isolation: the combined genotypic frequencies departed from Hardy-Weinberg equilibrium and the allele frequencies were different. The genetic distance between the 2 species is relatively small, suggesting that they are closely related.

Clinical response to supervised treatment of Colombian patients with cutaneous leishmaniasis was evaluated in a randomized controlled trial comparing 10 days versus 20 days of treatment with meglumine antimonate (20 mg Sb/kg/day). Masked examiners evaluated clinical response defined as 100% re-epithelialization of all lesions at 13 weeks and no relapses during 52 weeks of follow-up. The efficacy of meglumine antimonate for 10 days' treatment was 61% (28 of 46) compared to 67% (24 of 36) for 20 days. There was a significantly lower clinical response for children 5 years in both 10-day (11%) and 20-day (25%) groups compared to patients aged 5-14 years (67% and 75%, respectively) and 15 years or more (81% and 83%, respectively). Overall efficacy of treatment schedules was comparable, but lower than expected, mainly because of low efficacy in children. Pathogenicity of infection and pharmacokinetics may affect the treatment response in children. New therapeutic alternatives should be evaluated in trials that include children and women.