Lecciones aprendidas en el control de Aedes aegypti para afrontar el dengue y la emergencia de chikungunya en Iquitos, Perú / Lessons learned in the control of Aedes aegypti to address dengue and the emergency of chikungunya in Iquitos, Peru

El dengue ha afectado a Iquitos desde 1990 causando varios brotes de gran impacto en la salud pública y por el que se desplegaron grandes esfuerzos para su control temporal. Actualmente, ante la expansión del virus chikungunya en las Américas y la amenaza de la emergencia del virus en Iquitos, reflexionamos a modo de lecciones aprendidas las actividades emprendidas en el área del control vectorial; la vigilancia epidemiológica; el diagnóstico y el manejo clínico durante los periodos de brotes de dengue, de modo que nos permita enfrentar mejor la amenaza de un brote del virus chikunguña en la ciudad más grande de la Amazonía peruana.

Dengue has affected Iquitos since 1990 causing outbreaks of major impact on public health and for this reason great efforts have been made for its temporal control. Currently, with the expansion of the chikungunya virus in the Americas and the threat of the emergence of the virus in Iquitos, we reflect on lessons learned by way of the activities undertaken in the area of vector control; epidemiological surveillance, diagnosis and clinical management during periods of outbreaks of dengue, in a way that will allow us to better face the threat of an outbreak of chikungunya virus in the largest city in the Peruvian Amazon.

Specificity of the rapid rK39 antigen-based immunochromatographic test Kalazar Detect(r) in patients with cutaneous leishmaniasis in Brazil

The aim of this study was to evaluate the specificity of a rapid immunochromatographic test that was developed to detect antibodies against the rK39 antigen for the diagnosis of visceral leishmaniasis (VL). This evaluation was performed using sera from patients with a confirmed diagnosis of active cutaneous leishmaniasis. The sera from 272 patients with a confirmed diagnosis of localised cutaneous leishmaniasis (CL) who resided in an area endemic for Leishmania braziliensis in Brazil were obtained before the initiation of antileishmanial treatment. Kalazar Detect(r)(InBios, Seattle, WA) recombinant K39 antigen-based immunochromatographic strips were used according to the manufacturer's instructions. The test results were evaluated independently by two examiners in sequential order. The positive controls for the test included five serum samples from five patients with parasitologically confirmed diagnosis of VL caused by Leishmania infantum in Brazil. Overall, 100% of the samples obtained from patients with CL were negative, confirming the absence of a serological cross-reaction for individuals with cutaneous disease when these patients were evaluated using the rapid test. The lack of a cross-reaction in patients who were infected by parasites of the same genus highlights the specificity of the rK39 antigen for the diagnosis of VL in areas with the sympatric circulation of L. braziliensis and L. infantum.

Genus-specific kinetoplast-DNA PCR and parasite culture for the diagnosis of localised cutaneous leishmaniasis: applications for clinical trials under field conditions in Brazil

The positivities of two methods for the diagnosis of localised cutaneous leishmaniasis (CL) were estimated in 280 patients enrolled in a clinical trial. The trial was conducted in an endemic area of Leishmania (Viannia) braziliensis and trial participants were patients with skin ulcers and positive leishmanin skin tests. Patients underwent aspirative skin punctures of the ulcerated lesions and lymph nodes for in vitro cultures, which were processed under field conditions at the local health centre. Skin lesion biopsies were tested at a reference laboratory using kinetoplastid DNA (kDNA)-PCR to detect DNA. The median time required to obtain a positive culture from the skin samples was seven days and the contamination rate of the samples was 1.8 percent. The positivities of the cultures from skin lesions, kDNA-PCR and the combination of the two methods were 78.2 percent (95 percent CI: 73-82.6 percent), 89.3 percent (95 percent CI: 85.1-92.4 percent) and 97.1 percent (95 percent CI: 94.5-98.5 percent). We conclude that parasite culture is a feasible method for the detection of Leishmania in field conditions and that the combination of culture and PCR has a potential role for the diagnosis of CL in candidates for clinical trials.

Características clínicas da leishmaniose tegumentar em criancas de 0 a 5 anos em uma área endêmica de Leishmania (Viannia) braziliensis / Clinical findings of tegumentary leishmaniasis in children under five years of age in an endemic area of Leishmania (Viannia) braziliensis

Para caracterizar a clínica da leishmaniose tegumentar em criancas de 0 a 5 anos de idade, foram avaliadas, retrospectivamente, 4.464 fichas clínicas do Centro de Saúde de Corte de Pedra, Presidente Tancredo Neves, Bahia, Brasil, área endêmica de leishmaniose tegumentar americana, entre maio de 1987 e dezembro de 1995. Foram registrados neste período 4.275 casos novos de leishmaniose, dos quais, 491 (11,5 por cento) correspondiam a criancas de 0 a 5 anos. A razão entre gênero masculino e feminino nas criancas foi 1,1:1. A forma clínica predominante foi a cutânea (98 por cento) e as lesões ulceradas foram as mais freqüentes (99 por cento). A localizacão das lesões ocorreu, principalmente, acima da cintura (p<0,05), e 35,5 por cento apresentaram lesões múltiplas. A magnitude da doenca em criancas, a freqüência semelhante observada em ambos os gêneros e a localizacão das lesões sugere a possibilidade de transmissão vetorial no domicílio ou peridomicílio.

Factores de riesgo para la transmisión de leishmaniasis cutánea en niños de 0 a 5 años en un área endémica de Leishmania (Viannia) braziliensis / Risk factors for cutaneous leishmaniasis transmission in children aged 0 to 5 years in an endemic area of Leishmania (Viannia) braziliensis

Fue realizado un estudio caso-control pareado en Corte de Pedra, Bahía, Brasil, área endémica de Leishmania (Viannia) braziliensis para evaluar los diferentes factores de riesgo asociados a la presencia de leishmaniasis cutánea en niños de 0 a 5 años. Fueron considerados como casos, los niños con prueba de leishmanina positiva y que presentaban en el examen físico, una o más lesiones clínicas, activas o cicatrizales, compatibles con leishmaniasis cutánea. Fueron seleccionados 40 casos y 71 controles que fueron pareados por edad y área de residencia. La presencia de algún otro miembro de la familia con antecedente de leishmaniasis cutánea durante el año anterior a la aparición de la enfermedad en el niño demostró ser un importante factor de riesgo (MÕR MH = 17,75; IC95 por ciento: 4,08-77,25). No se encontraron evidencias de asociación con otros factores, como hábitos del niño dentro y fuera de casa, características de la vivienda y del peridomicilio, presencia de vectores y animales como probables reservorios. Estos hallazgos apoyan la hipótesis que el ser humano podría comportarse como un posible reservorio y servir de fuente de contagio para este grupo de edad.