Community deployment of a synthetic pheromone of the sand fly Lutzomyia longipalpis co-located with insecticide reduces vector abundance in treated and neighbouring untreated houses: Implications for control of Leishmania infantum.

BACKGROUND: The rising incidence of visceral leishmaniasis due to Leishmania infantum requires novel methods to control transmission by the sand fly vector. Indoor residual spraying of insecticide (IRS) against these largely exophilic / exophagic vectors may not be the most effective method. A synthetic copy of the male sex-aggregation pheromone of the key vector species Lutzomyia longipalpis in the Americas, was co-located with residual pyrethroid insecticide, and tested for its effects on vector abundance, hence potential transmission, in a Brazilian community study. METHODS: Houses within eight defined semi-urban blocks in an endemic municipality in Brazil were randomised to synthetic pheromone + insecticide or to placebo treatments. A similar number of houses located >100m from each block were placebo treated and considered as "True Controls" (thus, analysed as three trial arms). Insecticide was sprayed on a 2.6m2 surface area of the property boundary or outbuilding wall, co-located within one metre of 50mg synthetic pheromone in controlled-release dispensers. Vector numbers captured in nearby CDC light traps were recorded at monthly intervals over 3 months post intervention. Recruited sentinel houses under True Control and pheromone + insecticide treatments were similarly monitored at 7-9 day intervals. The intervention effects were estimated by mixed effects negative binomial models compared to the True Control group. RESULTS: Dose-response field assays using 50mg of the synthetic pheromone captured a mean 4.8 (95% C.L.: 3.91, 5.80) to 6.3 (95% C.L.: 3.24, 12.11) times more vectors (female Lu. longipalpis) than using 10mg of synthetic pheromone. The intervention reduced household female vector abundance by 59% (C.L.: 48.7, 66.7%) (IRR = 0.41) estimated by the cross-sectional community study, and by 70% (C.L.: 56.7%, 78.8%) estimated by the longitudinal sentinel study. Similar reductions in male Lu. longipalpis were observed. Beneficial spill-over intervention effects were also observed at nearby untreated households with a mean reduction of 24% (95% C.L.: 0.050%, 39.8%) in female vectors. The spill-over effect in untreated houses was 44% (95% C.L.: 29.7%, 56.1%) as effective as the intervention in pheromone-treated houses. Ownership of chickens increased the intervention effects in both treated and untreated houses, attributed to the suspected synergistic attraction of the synthetic pheromone and chicken kairomones. The variation in IRR between study blocks was not associated with inter-household distances, household densities, or coverage (proportion of total households treated). CONCLUSIONS: The study confirms the entomological efficacy of the lure-and-kill method to reduce the abundance of this important sand fly vector in treated and untreated homesteads. The outcomes were achieved by low coverage and using only 1-2% of the quantity of insecticide as normally required for IRS, indicating the potential cost-effectiveness of this method. Implications for programmatic deployment of this vector control method are discussed.

Acute Chagas disease in Brazil from 2001 to 2018: A nationwide spatiotemporal analysis.

BACKGROUND: In Brazil, acute Chagas disease (ACD) surveillance involves mandatory notification, which allows for population-based epidemiological studies. We conducted a nationwide population-based ecological analysis of the spatiotemporal patterns of ACD notifications in Brazil using secondary surveillance data obtained from the Notifiable Diseases Information System (SINAN) maintained by Brazilian Ministry of Health. METHODOLOGY/PRINCIPAL FINDINGS: In this nationwide population-based ecological all cases of ACD reported in Brazil between 2001 and 2018 were included. Epidemiological characteristics and time trends were analyzed through joinpoint regression models and spatial distribution using microregions as the unit of analysis. A total of 5,184 cases of ACD were recorded during the period under study. The annual incidence rate in Brazil was 0.16 per 100,000 inhabitants/year. Three statistically significant changes in time trends were identified: a rapid increase prior to 2005 (Period 1), a stable drop from 2005 to 2009 (Period 2), followed by another increasing trend after 2009 (Period 3). Higher frequencies were noted in males and females in the North (all three periods) and in females in Northeast (Periods 1 and 2) macroregions, as well as in individuals aged between 20-64 years in the Northeast, and children, adolescents and the elderly in the North macroregion. Vectorial transmission was the main route reported during Period 1, while oral transmission was found to increase significantly in the North during the other periods. Spatiotemporal distribution was heterogeneous in Brazil over time. Despite regional differences, over time cases of ACD decreased significantly nationwide. An increasing trend was noted in the North (especially after 2007), and significant decreases occurred after 2008 among all microregions other than those in the North, especially those in the Northeast and Central-West macroregions. CONCLUSIONS/SIGNIFICANCE: In light of the newly identified epidemiological profile of CD transmission in Brazil, we emphasize the need for strategically integrated entomological and health surveillance actions.

Alterações nutricionais e metabólicas em pacientes com Aids em uso de terapia antirretroviral / Nutricional and metabolic changes in patients with Aids in antiretroviral therapy

alterações nutricionais e suas complicações podem tornar indivíduos soropositivos mais suscetíveis a infecções oportunistas e reduzir aeficácia dos medicamentos. Objetivo: avaliar as alterações nutricionais e metabólicas em pacientes portadores de aids, em uso de TARV atendidos a nível ambulatorial em um hospital do Nordeste brasileiro. Métodos: foram estudados transversalmente 31 pacientes, atendidos ambulatorialmente, através deparâmetros antropométricos e bioquímicos. Resultados: os pacientes foram classificados como eutróficos segundo o IMC, porém apresentaram reduçãodas reservas gordurosas em membros superiores, refletindo lipodistrofia, associada a dislipidemia mista, como provável consequência da TARV. Anemia foi encontrada em ambos os sexos. O tempo de diagnóstico não se correlacionou com o estado nutricional. Conclusão: alterações nutricionais e metabólicas em pacientes com aids podem ser minimizadas através de adequada terapia medicamentosa e dietoterápica

nutritional changes and its complications can become HIV-positive individuals more suscetible to opportunistic infections and reduce the effectiveness of medicines. Objective: assess the nutritional and metabolic changes in patients with AIDS, in antiretroviral theraphy treated at out patient treatment at a hospital in Northeast Brazil. Methods: we studied 31 patients across, patient clinic, using the anthropometric and biochemical parameters.Results: Patients were classified as normal according to BMI, but showed reduction of adipose reserves in the upper limbs, reflecting lipodystrophy associated with mixed dyslipidemia, as probable consequence of HAART. Anemia was found in both sexes. The time of diagnosis did not correlate with nutritional status. Conclusion: nutritional and metabolic changes in aids patients can be minimized through proper drug therapy and diet therapy.

[In vitro insecticidal activity of seed neem oil on Lutzomyia longipalpis (Diptera: Psychodidae)]. / Atividade inseticida in vitro do óleo de sementes de nim sobre Lutzomyia longipalpis (Diptera: Psychodidae).

Lutzomyia longipalpis is the main vector of visceral leishmaniasis in Brazil. The objective was to evaluate the effect of oil from (Azadirachta indica) neem seeds on eggs, larvae and adults of the vector. The insects were captured in the field and kept in the laboratory at +/- 27 °C and 80% relative humidity. Five treatments with different concentrations were performed using two negative controls (distilled water and Tween 80) and a positive control. The eggs were sprayed with the oil at different concentrations and the number of hatched larvae evaluated for 10 days. Mortality of larvae was observed to pupation and adult mortality was observed after 24, 48, and 72 hours. Statistical analysis was performed by Tukey test at 5% probability. The highest oil concentration of eggs obtained 65.16 +/- 3.24% efficacy for reducing egg hatching. The test with larvae showed 67.75 +/- 2.21% efficacy at a concentration of 100 mg.mL⁻¹. In adults, the efficacy of the 100 mg.mL⁻¹ concentration was 96.64 +/- 4.11% after 24 hours. The phytochemical analysis revealed the presence of triterpenes. These results demonstrate the potential use of this oil in the control of this vector.

Atividade inseticida in vitro do óleo de sementes de nim sobre Lutzomyia longipalpis (Diptera: Psychodidae) / In vitro insecticidal activity of seed neem oil on Lutzomyia longipalpis (Diptera: Psychodidae)

Lutzomyia longipalpis é o principal vetor da Leishmaniose visceral no Brasil. O objetivo deste trabalho foi avaliar o efeito do óleo de sementes de nim (Azadirachta indica) sobre ovos, larvas e adultos do vetor. Os insetos foram capturados no campo e mantidos no laboratório a ± 27 °C e 80 por cento de umidade relativa. Cinco tratamentos com diferentes concentrações foram realizados, usando-se dois controles negativos, um com água destilada e outro com Tween 80 (3 por cento) e um controle positivo com cipermetrina. Os ovos foram borrifados com o óleo em diferentes concentrações e avaliou-se o número de larvas eclodidas por 10 dias consecutivos. A mortalidade das larvas foi observada até a pupação, e a mortalidade dos adultos foi observada após 24, 48, e 72 horas. A análise estatística foi feita pelo teste de Tukey a 5 por cento de probabilidade. No teste com ovos, a maior concentração obteve 65,16 ± 3,24 por cento de eficácia. O teste com larvas apresentou 67,75 ± 2,21 por cento de eficácia na concentração de 100 mg.mL-1. Com adultos, a eficácia na concentração de 100 mg.mL-1 foi de 96,64 ± 4,11 por cento, após 24 horas. A análise fitoquímica revelou a presença de triterpenos. Esses resultados demonstram o potencial uso desse óleo no controle deste vetor.

Lutzomyia longipalpis is the main vector of visceral leishmaniasis in Brazil. The objective was to evaluate the effect of oil from (Azadirachta indica) neem seeds on eggs, larvae and adults of the vector. The insects were captured in the field and kept in the laboratory at ± 27 °C and 80 percent relative humidity. Five treatments with different concentrations were performed using two negative controls (distilled water and Tween 80) and a positive control. The eggs were sprayed with the oil at different concentrations and the number of hatched larvae evaluated for 10 days. Mortality of larvae was observed to pupation and adult mortality was observed after 24, 48, and 72 hours. Statistical analysis was performed by Tukey test at 5 percent probability. The highest oil concentration of eggs obtained 65.16 ± 3.24 percent efficacy for reducing egg hatching. The test with larvae showed 67.75 ± 2.21 percent efficacy at a concentration of 100 mg.mL-1. In adults, the efficacy of the 100 mg.mL-1 concentration was 96.64 ± 4.11 percent after 24 hours. The phytochemical analysis revealed the presence of triterpenes. These results demonstrate the potential use of this oil in the control of this vector.