2,021 research outputs found
Leishmaniasis: new approaches to disease control.
The leishmaniases afflict the world's poorest populations. Among the two million new cases each year in the 88 countries where the disease is endemic (fig 1), it is estimated that 80% earn less than $2 a day. Human infections with Leishmania protozoan parasites, transmitted via the bite of a sandfly, cause visceral, cutaneous, or mucocutaneous leishmaniasis. The global burden of leishmaniasis has remained stable for some years, causing 2.4 million disability adjusted life years (DALYs) lost and 59 000 deaths in 2001. Neglected by researchers and funding agencies, leishmaniasis control strategies have varied little for decades, but in recent years there have been exciting advances in diagnosis, treatment, and prevention. These include an immunochromatographic dipstick for diagnosing visceral leishmaniasis; the licensing of miltefosine, the first oral drug for visceral leishmaniasis; and evidence that the incidence of zoonotic visceral leishmaniasis in children can be reduced by providing dogs with deltamethrin collars. There is also hope that the first leishmaniasis vaccine will become available within a decade. Here we review these developments and identify priorities for research
Forecasting temporal dynamics of cutaneous leishmaniasis in Northeast Brazil.
IntroductionCutaneous leishmaniasis (CL) is a vector-borne disease of increasing importance in northeastern Brazil. It is known that sandflies, which spread the causative parasites, have weather-dependent population dynamics. Routinely-gathered weather data may be useful for anticipating disease risk and planning interventions.Methodology/principal findingsWe fit time series models using meteorological covariates to predict CL cases in a rural region of Bahía, Brazil from 1994 to 2004. We used the models to forecast CL cases for the period 2005 to 2008. Models accounting for meteorological predictors reduced mean squared error in one, two, and three month-ahead forecasts by up to 16% relative to forecasts from a null model accounting only for temporal autocorrelation.SignificanceThese outcomes suggest CL risk in northeastern Brazil might be partially dependent on weather. Responses to forecasted CL epidemics may include bolstering clinical capacity and disease surveillance in at-risk areas. Ecological mechanisms by which weather influences CL risk merit future research attention as public health intervention targets
Instructions on how to make an Outbreak of American Cutaneous Leishmaniasis
Outbreaks of American Cutaneous Leishmaniasis (ACL) are triggered by the confluence of multidimensional biological, climate, and social factors: the eco-epidemiological momentum. Despite the diversity of epidemiological scenarios, there are common “Ingredients for the recipe” to make an ACL outbreak. To describe the “Where”, “When”, and “Why” of this momentum could contribute to the understanding of the causes of epidemics, preventing their occurrence, and to define better strategies to control them. Typically, due to sylvatic-rural transmission, most urban ACL are still related in time and space to peripheral city deforestations, riparian forest, and green patches within the cities. Therefore, the “Where” of the ACL outbreaks could be characterized in the space as an edge effect, and afterwards the “When” of this edge could be categorized as an ephemeral, transient or permanent. The “Why” question is far more complex, as it includes the exposure of humans to vector due to anthropic activities in each edge scenario. The evidence for ACL outbreak control strategies: barricading the edge by chemical and physical barriers, environmental management, and individual prevention, were reviewed. Answers to questions regarding these “Where”, “When”, “Why”, and “How to control” guided the content of the questions to be asked in the new focus of ACL transmission, not only to mitigate current transmission and prevent future outbreaks, but also to highlight the biological factors that might contribute to the possibility of an epidemic, and those conditions that modulate its actual probability, the climate and the social determination of risk.Fil: Salomón, Oscar Daniel. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Ministerio de Salud. Instituto Nacional de Medicina Tropical; Argentin
Environmental Changes and the Geographic Spreading of American Cutaneous Leishmaniasis in Brazil
Molecular diagnosis of American Cutaneous Leishmaniasis (ACL) in dogs from an endemic area in Pernambuco State, Brazil
A survey was carried out to detect American cutaneous leishmaniasis (ACL) among dogs in an area where a human outbreak had occurred in the state of Pernambuco, in northeastern Brazil. Domiciled dogs living in the district of Três Ladeiras, Igarassu were used in the present study. The following procedures were performed: The Polymerase Chain Reaction (PCR) (n = 126); the Immunofluorescence Antibody Test (IFAT) (n = 80); and a parasitological examination to detect amastigote forms of Leishmania sp. in skin lesions (n = 43). Associations between the infection in animals and the clinical and epidemiological factors were analyzed using Fisher's exact test or the Pearson’s chi-squared test. In total, 46.8% (59/126) of the samples tested were PCRpositive. Although a higher frequency of positivity was detected among males (46.3 %) and animals aged between 3 and 4 years (50.0 %), no significant associations were recorded for these variables (p> 0.05). Similarly, the clinical signs and aspects related to the environment in which the animal lives did not differ significantly, but differences were recorded for the variable locality. In the IFAT, only 6.2% (5/80) of the dogs were positive and no amastigote forms of Leishmania sp. were detected
Surto de leishmaniose cutânea americana na cidade de Tartagal, Província de Salta, Argentina, 1993
An American cutaneous leishmaniasis outbreak, with cases clustering during 1993 in Tartagal city, Salta, was reported. The outbreak involved 102 individuals, 43.1% of them with multiple ulcers. Age (mean: 33 years old) and sex distribution of cases (74.5% males), as well as working activity (70 forest-related), support the hypothesis of classical forest transmission leishmaniasis, despite the fact that the place of permanent residence was in periurban Tartagal. Moreover, during July, sandflies were only collected from one of the 'deforestation areas'. Lutzomyia intermedia was the single species of the 491 phlebotomines captured, reinforcing the vector incrimination of this species. Most infections must have been acquired during the fall (April to June), a pattern consistent with previous sandfly population dynamics data. Based on the epidemiological and entomological results, it was advised not to do any vector-targeted periurban control measures during July. Further studies should be done to assess if the high rate of multiple lesions was due to parasite factors or to infective vector density factors.Foi registrado um surto de leishmaniose cutânea americana, com casos agrupados na cidade de Tartagal, província de Salta, durante 1993. O surto envolveu 102 indivíduos, 43,1% deles com úlceras múltiplas. A idade (média: 33 anos) e distribuição de sexo nos casos (74,5% homens) como também a ocupação (70% relacionado com a floresta), apóia a hipótese da clássica transmissão de leishmaniose na floresta, apesar do fato de que o lugar de residência permanente estava na área periurbana de Tartagal. Além disso, durante julho, foram colecionados flebótomos só de uma área de desmatamento. Lutzomyia intermedia foi a única espécie dos 491 flebotomíneos capturados e reforça a incriminação de vetor desta espécie. A maioria das infecções deve ter sido adquirida durante o outono (abril para junho), um padrão consistente com dados prévios sob a dinâmica de população de flebótomos. Com base nos resultados, epidemiológicos e entomológicos foi aconselhado não fazer qualquer controle sobre vetores na área periurbana durante julho. Mais adiante deveriam ser feitos estudos para avaliar se a alta taxa de lesões múltiplas foi devido a fatores do parasita ou a fatores de densidade do vetor
AMERICAN CUTANEOUS LEISHMANIASIS WITH UNUSUAL CLINICAL PRESENTATION AND RESPONSE TO TREATMENT
The clinical manifestations and prognosis of cutaneous leishmaniasis (CL) can be influenced by the immune response of the patient and the species of the parasite. A case of atypical clinical presentation of CL, with development of non-characteristic lesions, poor response to therapy, and a long time to resolution is reported. Confirmatory laboratory tests included parasite detection, indirect immunofluorescence, Montenegro skin test, polymerase chain reaction, and parasite identification by multilocus enzyme electrophoresis. The parasite was identified as Leishmaniabraziliensis. The lesion was unresponsive to three complete courses of N-methylglucamine antimoniate intramuscular, and to treatment with pentamidine. The patient did not tolerate amphotericin B. The lesion finally receded after treatment with intravenous N-methylglucamine antimoniate. It is essential to ensure the accuracy of diagnosis and the appropriate treatment, which can include the use a second choice drug or a different route of administration
Seventeen years of American cutaneous leishmaniasis in a Southern Brazilian municipality
Foram revistos os registros de 151 pacientes diagnosticados com leishmaniose tegumentar americana (LTA) de 1993-2009 no município de Japurá, Paraná, Brasil. Sexo, idade, profissão, local de residência, localização das lesões, tipo e número de lesões foram analisadas. A taxa de prevalência de LTA foi 11,5/10.000 hab, dos quais 84,7% eram do sexo masculino, 58,3% viviam na área rural e 49,0% eram agricultores. A faixa etária mais freqüente foi entre 30 a 39 anos (26,6%). Lesões de pele ocorreram em 92,7% dos pacientes com predominância nos membros inferiores (23,9%) e 49,1% dos registros não incluem o número e localização de lesões devido ao preenchimento incompleto. Ulceração única estava presente em 44,4%. Japurá é uma área endêmica para LTA, exigindo ações públicas e educação preventiva.We reviewed the records of 151 patients diagnosed with American cutaneous leishmaniasis (ACL) from 1993 to 2009 in the municipality of Japura, Paraná, Brazil. Gender, age, occupation, place of residence, location of lesions, type and number of lesions were analyzed. The prevalence rate of ACL was 11.5/10,000 hab, of which 84.7% were male, 58.3% lived in rural area and 49.0% were farmers. The most frequent age group was between 30 to 39 years (26.6%). Skin lesions occurred in 92.7% of the patients with predominance in the lower limbs (23.9%) and 49.1% of the records did not include the number of lesions location due to incomplete filling. A single ulceration was present in 44.4%. Japurá is an endemic area for ACL, requiring public actions and preventive education
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