Visceral leishmaniasis in Brazil: scenarios and challenges for the surveillance and control

Adaptation of the vector and displacement of infected dogs to previously disease-free areas challenges visceral leishmaniasis (VL) control, and leads to geographic dispersion and occurrence in urban and peri-urban areas. Continuous VL control measures over time must be applied with a wide geographic reach, along with better diagnosis practices and timely treatment. The high case-fatality of human VL in areas of recent introduction and its growing association with HIV impose the need for an early diagnosis, treatment and the adoption of active search for human and canine cases incorporated into the routine of periodic home visits by health professionals. The increasing on public rejection of canine euthanasia as a control measure, the limitations of canine therapy with the current available drugs, and the controversies regarding available vaccines for canine protection are discussed. Good prospects on the insecticide-impregnated collars as an effective control measure are emphasized.

Epidemiological aspects of pediculosis by Pediculus humanus capitis (Phthiraptera: Pediculidae) in Minas Gerais: a systematic review / Aspectos epidemiológicos da pediculose por Pediculus humanus capitis (Phthiraptera: Pediculidae) em Minas Gerais: uma revisão sistemática

Abstract Background Head lice, or head pediculosis, is a parasitosis considered a serious public health problem that affects mainly resource-limited countries. Objective To describe epidemiological aspects of the pediculosis capitis in Minas Gerais, in Brazil. Method This systematic review was conducted through the standards established by the Preferred Reporting Items in Systematic Reviews and Metanalyses (PRISMA). PubMed, LILACS, and SciELO databases, as well as the gray literature, were searched. Results Nine of 1,167 studies were included, published between 1988 and 2019. These studies reported a total prevalence of parasitosis that ranged from 1.4% to 57.4%. The prevalence of head lice ranged from 0.0% to 66.7% for males and 2.3% to 57.4% for females, thus being higher in black-skinned people (1.4% to 40.3%). Regarding age, the highest prevalence was 10-12 years old (45.3%). As for the characteristics of the hair, there was a greater infestation in people with long (16.0% to 79.5%), wavy (0.0% to 44.7%), dark (0.0% to 36.6%), with low capillary density (35.4%), and thick hair (39.2%). Conclusion Head pediculosis affects both sexes, different ages, and races, representing an important health problem in Minas Gerais, not only due to the presence of ectoparasite but also to the secondary complications that can be generated from this parasitism.

Resumo Introdução A pediculose de cabeça é uma parasitose considerada um sério problema de saúde pública, afetando principalmente países com recursos limitados. Objetivo Descrever os aspectos epidemiológicos da pediculose de cabeça em Minas Gerais, Brasil. Método Revisão sistemática conduzida por meio dos padrões estabelecidos pelo Preferred Reporting Items in Systematic Reviews and Metanalyses (PRISMA). Foram pesquisadas as bases de dados PubMed, LILACS e SciELO, bem como a literatura cinza. Resultados Nove de 1.167 estudos foram incluídos, publicados entre 1988 e 2019. Relatou-se uma prevalência total da parasitose que variou de 1,4% a 57,4%. Ela variou de 0,0% a 66,7% para homens e 2,3% a 57,4% para mulheres, sendo maior em pessoas de cor negra (1,4% a 40,3%). Em relação à idade, a maior prevalência foi de 10 a 12 anos (45,3%). Quanto às características dos cabelos, houve maior infestação em pessoas com cabelos longos (16,0% a 79,5%), ondulados (0,0% a 44,7%), escuros (0,0% a 36,6%), com baixa densidade capilar (35,4%) e fios grossos (39,2%). Conclusão A pediculose atinge ambos os sexos, diferentes idades e raças, representando um importante problema de saúde em Minas Gerais, não só pela presença do ectoparasita, mas também pelas complicações secundárias que podem ser geradas desse parasitismo.

Spatial and spatiotemporal patterns of human visceral leishmaniasis in an endemic southeastern area in countryside Brazil

ABSTRACT Visceral leishmaniasis (VL) has shown endemic pattern and epidemic episodes in urban and rural areas, however, there are still gaps in knowledge with regards to disease transmission. This study aimed to analyze the spatiotemporal dispersion of VL cases in the municipality of Araçuaí, Minas Gerais. A study of confirmed VL cases was conducted considering the endemic and epidemic periods between 2012 and 2017. The incidence rate was calculated, and for spatial analysis, the kernel map, directional distribution ellipse, and space-time scanning techniques were used. The correlations between VL cases and exposure variables (precipitation, humidity, and temperature) were calculated. The mean incidence of VL in the endemic period was 18.5 (95% confidence interval (CI) 5.9-32.5) and 44.4 in the epidemic period (95%CI, 12.0-28.6) by 100,000 inhabitants. The relative risk for the epidemic period was 2.4 (95% CI 1.4-4.1) when compared to the endemic period. A higher incidence of the disease was observed in rural areas of the municipality. Kernel mapping analysis revealed hotspots in the urban area of the municipality. The directional distribution ellipse encompasses the urban perimeter and part of the rural area of the municipality, expanding eastward during the epidemic period. Spatial analysis revealed a high-risk cluster for VL in rural areas. A positive correlation was observed between VL cases and temperature during the endemic period. Spatial analysis allowed us to outline the epidemiological scenario of human VL cases. These findings may be useful in case surveillance and in the work of health professionals and managers in Brazil.

Factors associated with deaths from dengue in a city in a metropolitan region in Southeastern Brazil: a case-control study

ABSTRACT Background: Dengue is a public health problem in Brazil. Therefore, this study aimed to analyze factors associated with deaths from dengue in residents of the municipality of Contagem, Metropolitan Region of Belo Horizonte, state of Minas Gerais, Brazil, during the 2016 epidemic. Methods: To determine the factors associated with deaths due to dengue, we used a logistic regression model (univariate and multivariable) in which the response variable (outcome) was death due to dengue. Independent variables analyzed included demographic variables and those related to symptoms, treatment, hospitalization, testing, comorbidities, and case history. Results: The factors associated with dengue deaths in the final multivariable model [p < 0.05; 95% confidence interval (CI)] were age (OR = 1.07; 95%CI 1.03-1.11) and presence of bleeding (OR = 8.55; 95%CI 1.21-59.92). Conclusions: The results showed that age and the presence of bleeding factors increased the risk of dengue death. These findings indicate that warning signs of dengue should be routinely monitored, and patients should be instructed to seek medical attention when they occur. It is also emphasized that the parameters and epidemiological conditions of dengue patients need to be continuously investigated to avoid a fatal outcome.

Factors associated with the occurrence of dengue epidemics in Brazil: a systematic review / Factores asociados a la aparición de epidemias de dengue en Brasil: revisión sistemática / Fatores associados à ocorrência de epidemias de dengue no Brasil: uma revisão sistemática

ABSTRACT Objective. To identify and describe broadly the factors related to the occurrence of dengue epidemics in Brazil. Methods. Systematic review of studies published in Medline, Lilacs, PubMed, Cochrane, BVS, Web of Science, Scopus, and thesis and dissertations databases using descriptors cataloged in DeCs and MeSH on dengue and factors associated with the occurrence of epidemics, published from 2008 to 2018. Results. Thirty-five studies carried out in the country were selected. The epidemics recorded in Brazil were associated and/or correlated with multiple factors such as environment, socioeconomic conditions, climate, and aspects related to the vector, among others. Conclusions. Dengue epidemics are complex and multifactorial. The continuity of the vector control actions was found to be relevant to the reduction of Aedes aegypti and for disease control. To contain the spread of the disease, effective measures are needed in all sectors, including health, education, economy, population, business, and government. Actions for the early detection of cases of the disease can prevent new outbreaks of epidemics.

RESUMEN Objetivo. Determinar y describir de manera amplia los factores relacionados con la aparición de epidemias de dengue en Brasil. Métodos. Se llevó a cabo una revisión sistemática de los estudios publicados en MEDLINE, LILACS, PubMed, Cochrane, BVS, Web of Science, Scopus y en bases de datos de tesis y trabajos de final de grado con los descriptores catalogados en DeCS y MeSH sobre dengue y factores asociados con la aparición de epidemias publicados entre 2008 y 2018. Resultados. Se seleccionaron 35 estudios llevados a cabo en Brasil. Las epidemias registradas en el país se asociaron o se relacionaron con diversos factores, como el medioambiente, las condiciones socioeconómicas, el clima y aspectos relacionados con el vector, entre otros. Conclusiones. Las epidemias de dengue son complejas y multifactoriales. Se constató que la continuidad de las medidas de control de vectores es pertinente para la reducción de Aedes aegypti, así como para el control de la enfermedad. Para contener la propagación de la enfermedad son necesarias medidas eficaces en todos los sectores, como la salud, la educación, la economía, la población, las empresas y el gobierno. Las medidas de detección temprana de casos de la enfermedad pueden prevenir nuevos brotes de epidemias.

RESUMO Objetivo. Identificar e descrever, de forma geral, os fatores relacionados à ocorrência de epidemias de dengue no Brasil. Métodos. Revisão sistemática de estudos publicados entre 2008 e 2018 nas bases de dados MEDLINE, LILACS, PubMed, Cochrane, BVS, Web of Science e Scopus e em bancos de teses e dissertações, com o uso de descritores de dengue e de fatores associados à ocorrência de epidemias catalogados no portal DeCS/MeSH. Resultados. Trinta e cinco estudos realizados no Brasil foram selecionados. As epidemias registradas no país foram associadas e/ou correlacionadas a vários fatores como meio ambiente, condições socioeconômicas e climáticas, e aspectos relacionados ao vetor, entre outros. Conclusões. As epidemias de dengue são complexas e multifatoriais. Observou-se que ações contínuas de controle vetorial são essenciais para a redução da população de Aedes aegypti e o controle da doença. Para conter a propagação da dengue são necessárias medidas multissetoriais eficazes, abrangendo saúde, educação, economia, população, negócios e governo. As ações visando à detecção precoce de casos da doença contribuem para prevenir novos surtos epidêmicos.

Leishmania infection in humans, dogs and sandflies in a visceral leishmaniasis endemic area in Maranhão, Brazil

Leishmania infection in humans, dogs and sandflies was examined in the endemic visceral leishmaniasis (VL) municipality of Raposa, state of Maranhão, Brazil. In this study, we examined Leishmania chagasi infection in the blood serum of both humans and Canis familiaris and the natural Leishmania sp. infection rate in the sandfly vector, Lutzomyia longipalpis. Enzyme-linked immunosorbent assay, indirect immunofluorescence reaction and polymerase chain reaction were performed to detect Leishmania infections in humans, dogs and sandflies, respectively. Overall, 186 out of 986 studied human beings were infected with L. chagasi parasites, representing an infection prevalence of 18.9 percent. An even higher infection rate was detected in dogs, where 66 (47.8 percent) out of 138 were infected. Among all Lu. longipalpis captured (n = 1,881), only 26.7 percent were females. The Leishmania infection frequency for the vector Lu. longipalpis was 1.56 percent. Remarkably, all infected sandflies were found in the peridomiciliary area. Furthermore, a high incidence of asymptomatic forms of VL in the human and canine populations was observed. The results of this study suggest autochthonous transmission of L. chagasi in this endemic area for visceral leishmaniasis because infection by Leishmania sp. was identified in all important elements of the transmission chain.

Distribuição espacial e definição de áreas prioritárias para vigilância da leishmaniose visceral no município de São Luís, Maranhão, Brasil / Spatial distribution and definition of priority areas for surveillance of visceral leishmaniasis in São Luis, Maranhão, Brazil

Técnicas de análise espacial podem facilitar a tomada de decisões e garantir um planejamento estratégico para a alocação de recursos e implantação de medidas de controle da leishmaniose visceral. Este trabalho teve por objetivo analisar a distribuição espacial e identificar áreas prioritárias para a vigilância da leishmaniose visceral no município de São Luís – MA. Realizou-se um estudo ecológico, onde estrutura espacial das taxas de incidência de LV humana e a média de casos humanos e caninos foi avaliada considerando-se três períodos, 1999-2001, 2002-2004 e 2005-2007. Para análise do padrão espacial, foram utilizados os mapas de espalhamento de Moran (Box Map) e o índice de Moran local (Moran Map), obtidos por meio do software TerraView 3.6.0. A LV apresentou os seguintes valores máximos de incidência, letalidade humana e percentual de positividade canina, respectivamente: 15,8 casos por 100 mil habitantes (1999), 7,6% (2002) e 7,77 (2006). A distribuição espacial da incidência e média de casos humanos demonstra uma concentração de focos nos distritos da Vila Esperança, Tirirical e Itaqui-bacanga, com redução perceptível ao longo do período. Nestes distritos observa-se uma maior predominância de localidades com características intermediárias entre os ambientes urbano e rural. O mesmo ocorre na distribuição espacial da média de casos caninos, porém possui uma distribuição mais homogênea nos distritos sanitários do município. Os distritos sanitários do Centro, Bequimão e Coroadinho, que são áreas de maior urbanização, apresentam valores menores em relação à doença na área de estudo. Ao observarmos o percentual de casos humanos e caninos ocorrendo na mesma unidade de análise, constatamos que esta ocorrência conjunta da doença atinge valores de até 25%...

Spatial analysis techniques can facilitate decision-making and ensure a strategic planning for resource allocation and implementation of control measures for visceral leishmaniasis. This study aimed to analyze the spatial distribution of VL and identify priority areas for disease surveillance in São Luis - MA. We developed an ecological study, where the spatial structure of the incidence rates of human VL and the average of human and dog cases was evaluated considering three periods, 1999-2001, 2002-2004 and 2005-2007.The LV showed the following maximum values of incidence, human mortality and canine positivity index, respectively: 15.8 cases per 100.000 inhabitants (1999), 7.6% (2002) and 7.77 (2006). For spatial pattern analysis, we used the maps of scattering of Moran (Box Map) and the Local Moran's Index (Moran Map), obtained by the TerraView 3.6.0. The spatial distribution of the incidence and the average of human cases shows a concentration of foci of high priority in the districts of Vila Esperança, Tirirical and Itaqui-Bacanga, with a noticeable reduction during the period. In these districts there is a predominance of places with intermediate characteristics between urban and rural areas. The same occurs in the spatial distribution of the average canine cases, but has a more homogeneous distribution in the health districts of the municipality. The health districts of the Centro, Bequimão and Coroadinho, more urbanized areas, have lower values for the disease in the study area. When we observe the percentage of human and canine cases occurring in the same analysis unit, we found that in the last two periods, the occurrence of the disease is greater than 25%. As matter of fact, we believe that the use of spatial analysis tools for define priority areas for surveillance of visceral leishmaniasis is a feasible action and can achieve effective results in controlling the disease in the municipality.