Risk factors associated with the transmission of Andean cutaneous leishmaniasis.

This is a population-based case-control study of the risk factors associated with the transmission of Andean cutaneous leishmaniasis (uta) with a concurrent design comparing persons who developed uta against persons who did not. Cases and controls were matched by age. sex and place of residence. The unit of analysis was the person . The main exposure groups were: characteristics of the house, environmental characteristics around the house, and behaviour patterns of people. The study was carried out in five endemic regions of Peru. 187 cases and 335 controls were admitted to the study. Using matched and conditional logistic regression, in study areas of Lima & Ancash (region 1) and Piura (region 2) Departments we have identified risk factors which imply that transmission occurs (a) inside houses, (b) outside but close to houses, (c) around houses, but not clearly indoors or outdoors, and (d) away from houses. In region 1 we found three risk factors of type a, using a kerosene lamp (OR=6.6. c.i.:2.2-19.7), having a chimney (OR=4.9, c.i.: 1.9-12.5) and living in a stone house (OR=2.9, c.i.:1.6-5.2), one of type b, cutting wood (OR=7.4, c.i.:2.1-26.4), and three of type c. living in a house > 30 m from road (OR=3.9, c.i.: 1.4-10.7), with a vegetable garden (OR=2.8, c.i.: 1.1-4.1) and living in a house having > 6 persons (OR=4.2, c.i.:l.9-9.7). In region 2, we found four risk factors of type c, living in a house having an earth floor (OR=2.3. c.i.: 1.1-4.7), with cows (OR=1.3, c.i.: 1.1-1.6) and a neighbouring vegetable garden nearby (OR=2.9, c.i.:1.3-6.9), and living > 30 m from a river (OR=3.3, c.i.:3.1-8.4), and one of type d. doing irrigation work at night (OR=2.2, c.i.:1.2-4.2). The variability of risk factors between regions 1 and 2 can be explained by differences in (i) the frequency of exposures and (ii) the importance of factors. We conclude from OR's and PAR'S that much transmission occurs around houses. Certainly, some transmission is indoors: the population attributable risk for factors associated with indoor transmission in region 1 was 79%. suggesting the possibility of uta control by preventing biting in houses. It remains questionable how much transmission goes on outdoors

Prediction Score for Antimony Treatment Failure in Patients with Ulcerative Leishmaniasis Lesions

The manuscript is relevant because of the finding of a new risk factor for chemotherapy failure and the development of a prognosis score for cutaneous leishmaniasis. The proportion of patients that have multiple lesions in American Tegumentary Leishmaniasis (ATL) is considerable. Publications and our experience permit to estimate that they represent around 20% of the affected population from the Amazon basin with cutaneous lesions. In addition, about 1/3 of them would correspond to the concomitant distant lesions category, the novel risk factor identified with a very high odds ratio (20–30) associated. Such numbers merit study of concomitant distant ulcers category on its own, not only because of clinical management implications, but also to search for factors that are contributing to chemotherapy failure. Finally, the simple equation proposed in the manuscript can be easily adapted to smart phone technologies. Similar prognosis equations are scarce for other pathologies and do not exist for Cutaneous Leishmaniasis at all. The simplicity of this tool should be followed by subsequent epidemiologic studies in other ATL endemic regions

Field evaluation of a rapid diagnostic test (ParascreenTM) for malaria diagnosis in the Peruvian Amazon

BACKGROUND: The rapid diagnostic tests for malaria (RDT) constitute a fast and opportune alternative for non-complicated malaria diagnosis in areas where microscopy is not available. The objective of this study was to validate a RDT named Parascreen™ under field conditions in Iquitos, department of Loreto, Peru. Parascreen™ is a RDT that detects the histidine-rich protein 2 (HRP2) antigen from Plasmodium falciparum and lactate deshydrogenase from all Plasmodium species. METHODS: Parascreen™ was compared with microscopy performed by experts (EM) and polymerase chain reaction (PCR) using the following indicators: sensitivity (Se), specificity (Sp), positive (PV+) and negative predictive values (PV-), positive (LR+) and negative likehood ratio (LR-). RESULTS: 332 patients with suspected non-complicated malaria who attended to the MOH health centres were enrolled between October and December 2006. For P. falciparum malaria, Parascreen™ in comparison with EM, had Se: 53.5%, Sp: 98.7%, PV+: 66.7%, PV-: 97.8%, LR+: 42.27 and LR-: 0.47; and for non-P. falciparum malaria, Se: 77.1%, Sp: 97.6%, PV+: 91.4%, PV-: 92.7%, LR+: 32.0 and LR-: 0.22. The comparison of Parascreen™ with PCR showed, for P. falciparum malaria, Se: 81.8%, Sp: 99.1%, PV+: 75%, PV-: 99.4, LR+: 87.27 and LR-: 0.18; and for non-P. falciparum malaria Se: 76.1%, Sp: 99.2%, PV+: 97.1%, PV-: 92.0%, LR+: 92.51 and LR-: 0.24. CONCLUSIONS: The study results indicate that Parascreen™ is not a valid and acceptable test for malaria diagnosis under the field conditions found in the Peruvian Amazon. The relative proportion of Plasmodium species, in addition to the genetic characteristics of the parasites in the area, must be considered before applying any RDT, especially after the finding of P. falciparum malaria parasites lacking pfhrp2 gene in this region

Leishmania mexicana amazonensis isolated from a patient with fatal mucosal leishmaniasis

Faculdade de Medicina (FMD

Infection of laboratory-colonized Anopheles darlingi mosquitoes by Plasmodium vivax.

Anopheles darlingi Root is the most important malaria vector in the Amazonia region of South America. However, continuous propagation of An. darlingi in the laboratory has been elusive, limiting entomological, genetic/genomic, and vector-pathogen interaction studies of this mosquito species. Here, we report the establishment of an An. darlingi colony derived from wild-caught mosquitoes obtained in the northeastern Peruvian Amazon region of Iquitos in the Loreto Department. We show that the numbers of eggs, larvae, pupae, and adults continue to rise at least to the F6 generation. Comparison of feeding Plasmodium vivax ex vivo of F4 and F5 to F1 generation mosquitoes showed the comparable presence of oocysts and sporozoites, with numbers that corresponded to blood-stage asexual parasitemia and gametocytemia, confirming P. vivax vectorial capacity in the colonized mosquitoes. These results provide new avenues for research on An. darlingi biology and study of An. darlingi-Plasmodium interactions

Control of mucocutaneous leishmaniasis, a neglected disease: results of a control programme in Satipo Province, Peru.

Mucocutaneous leishmaniasis (MCL) is an important health problem in many rural areas of Latin America, but there are few data on the results of programmatic approaches to control the disease. We report the results of a control programme in San Martin de Pangoa District, which reports one of the highest prevalences of MCL in Peru. For 2 years (2001--2002), the technicians at the health post were trained in patient case management, received medical support and were supplied with antimonials. An evaluation after 2 years showed the following main achievements: better diagnosis of patients, who were confirmed by microscopy in 34% (82/240) of the cases in 2001 and 60% of the cases (153/254) in 2002; improved follow-up during treatment: 237 of 263 (90%) patients who initiated an antimonial therapy ended the full treatment course; improved follow-up after treatment: 143 of 237 (60%) patients who ended their full treatment were correctly monitored during the required period of 6 (cutaneous cases) or 12 (mucosal cases) months after the end of treatment. These achievements were largely due to the human and logistical resources made available, the constant availability of medications and the close collaboration between the Ministry of Health, a national research institute and an international non-governmental organization. At the end of this period, the health authorities decided to register a generic brand of sodium stibogluconate, which is now in use. This should allow the treatment of a significant number of additional patients, while saving money to invest in other facets of the case management

Human mucocutaneous leishmaniasis in Três Braços, Bahia - Brazil : an area of Leishmania braziliensis braziliensis transmission. II. Cutaneous disease. Presentation and evolution

Foram analisados os dados clínicos de 182 pacientes com leishmaniose cutânea, provavelmente causada por Leishmania braziliensis braziliensis. Sessenta e oito por cento apresentavam uma única lesão, usualmente uma úlcera, na terça parte inferior anterior da tíbia. Todos os grupos etários estavam representados e muitos apresentaram histórico de um a dois meses. Treze por cento apresentavam lesões fechadas de natureza verrucosa ou em placa. Após tratamento, a evolução destas lesões foi relacionada à regularidade da terapia por antimônio. Embora a cura usualmente ocorresse em três meses, o tempo de cicatrização, após o início de tratamento, foi variável e relativo ao tamanho da lesão (p < 0.01). Em geral a lesão fechava quando era dado suficiente antimônio como tratamento. Sete entre dez pacientes que apresentavam teste cutâneo negativo para leishmania tomavam positivos após o tratamento. Observou-se por fluorescência indireta, um declínio significante nos títulos de anticorpos em pacientes acompanhados durante e após a terapia. _________________________________________________________________________________ ABSTRACTThe clinical records of 182 patients with cutaneous leishmaniasis probably due to Leishmania braziliensis braziliensis are analysed. 68% had a single lesion which was usually an ulceron the lower anterior tibial third. Many had short histories of one to two months and all age groups were represented 13% had closed lesions of a verrucose or plaque like nature. Evolution of these skin lesions after treatment was related to the regularity of antimony therapy. Although healing usually occurred in three months, the time to scarring after commencing treatment was variable and related to the size ofthe lesion (p < 0.01). Usually if sufficient antimony treatment was given the lesion closed. Seven of the ten patients with initially negative leishmanin skin tests converted to positive after treatment. A significant decline of indirect fluorescent antibody titres occurred in patients followed, during and after therapy

First-Line Therapy for Human Cutaneous Leishmaniasis in Peru Using the TLR7 Agonist Imiquimod in Combination with Pentavalent Antimony

Neglected tropical diseases (NTDs) are a group of tropical infections including trypanosomiasis, filariasis, schistosomiasis, onchocerciasis, leishmaniasis and other such diseases of poverty. Of the classic neglected diseases, leishmaniasis has among the highest level of morbidity and mortality. Infection with Leishmania parasites causes severe disease in humans, including fatal visceral leishmaniasis and cutaneous leishmaniasis resulting in severe scarring, often in the face. This is a difficult infection to treat because the current therapies are generally poorly effective. The present study carried out a placebo-controlled, double-blinded study to investigated whether a combined therapy with imiquimod plus pentavalent antimony was superior to the standard therapy of pentavalent antimony alone as a first-line treatment for cutaneous leishmaniasis in Peru. A higher cure rate with the combination therapy was observed, but could not be conclusively proven