Persistence of Schistosomiasis-Related Morbidity in Northeast Brazil: An Integrated Spatio-Temporal Analysis.

OBJECTIVE: To analyze the temporal trend and spatial patterns of schistosomiasis-related morbidity in Northeast Brazil, 2001-2017. METHODS: Ecological study, of time series and spatial analysis, based on case notifications and hospital admission data, as provided by the Ministry of Health. RESULTS: Of a total of 15,574,392 parasitological stool examinations, 941,961 (6.0%) were positive, mainly on the coastline of Pernambuco, Alagoas and Sergipe states. There was a reduction from 7.4% (2002) to 3.9% (2017) of positive samples and in the temporal trend of the detection rate (APC-11.6*; Confidence Interval 95%-13.9 to -9.1). There was a total of 5879 hospital admissions, with 40.4% in Pernambuco state. The hospitalization rate reduced from 0.82 (2001) to 0.02 (2017) per 100,000 inhabitants. CONCLUSION: Despite the reduction in case detection and hospitalizations, the persistence of focal areas of the disease in coastal areas is recognized. This reduction may indicate a possible positive impact of control on epidemiological patterns, but also operational issues related to access to healthcare and the development of surveillance and control actions in the Unified Health System.

Comparison of serological and molecular tests to investigate Leishmania spp. infections in stray dogs from an area of intense visceral leishmaniasis transmission in Brazil.

The aim of this study was to investigate the level of exposure to Leishmania infection in stray dogs in an area of intense visceral leishmaniasis transmission in the state of Pernambuco, Brazil. Blood samples from 178 dogs were analyzed using serological and molecular assays: rapid immunochromatographic test (ICT), enzyme-linked immunosorbent assay (ELISA), immunofluorescence antibody test (IFAT), and conventional and quantitative polymerase chain reaction (cPCR and qPCR). Positivity values obtained with serological tests were 71.4% (127/178), 70.2% (125/178), and 50.6% (90/178) using ICT, ELISA, and IFAT, respectively, with 38.8% (69/178) of the dogs were simultaneously positive for all three tests. The positivity values obtained with cPCR and qPCR were 20.2% (36/178) and 38.8% (69/178), respectively, with 11.8% (21/178) testing positive in both molecular assays. Overall, 87.1% (155/178) were positive for anti-Leishmania spp. antibodies and/or Leishmania spp. DNA. Positivity to one or more tests was statistically associated with lymphadenomegaly, skin lesions, lymphocytosis, anemia and hyperproteinemia. The results of this study revealed a high level of exposure to Leishmania in stray dogs in an area of intense human visceral leishmaniasis transmission, suggesting that dogs play a role as reservoirs in the transmission cycle of this zoonosis.

Comparison of serological and molecular tests to investigate Leishmania spp. infections in stray dogs from an area of intense visceral leishmaniasis transmission in Brazil / Comparação de testes sorológicos e moleculares para investigar infecções por Leishmania spp. em cães errantes de uma área de intensa transmissão de leishmaniose visceral no Brasil

Abstract The aim of this study was to investigate the level of exposure to Leishmania infection in stray dogs in an area of intense visceral leishmaniasis transmission in the state of Pernambuco, Brazil. Blood samples from 178 dogs were analyzed using serological and molecular assays: rapid immunochromatographic test (ICT), enzyme-linked immunosorbent assay (ELISA), immunofluorescence antibody test (IFAT), and conventional and quantitative polymerase chain reaction (cPCR and qPCR). Positivity values obtained with serological tests were 71.4% (127/178), 70.2% (125/178), and 50.6% (90/178) using ICT, ELISA, and IFAT, respectively, with 38.8% (69/178) of the dogs were simultaneously positive for all three tests. The positivity values obtained with cPCR and qPCR were 20.2% (36/178) and 38.8% (69/178), respectively, with 11.8% (21/178) testing positive in both molecular assays. Overall, 87.1% (155/178) were positive for anti-Leishmania spp. antibodies and/or Leishmania spp. DNA. Positivity to one or more tests was statistically associated with lymphadenomegaly, skin lesions, lymphocytosis, anemia and hyperproteinemia. The results of this study revealed a high level of exposure to Leishmania in stray dogs in an area of intense human visceral leishmaniasis transmission, suggesting that dogs play a role as reservoirs in the transmission cycle of this zoonosis.

Resumo O objetivo deste estudo foi investigar o nível de exposição à infecção por Leishmania em cães errantes de uma área de transmissão intensa de leishmaniose visceral no estado de Pernambuco. Amostras de sangue de 178 cães foram avaliadas por testes sorológicos e moleculares: teste imunocromatográfico (IC), ensaio imunoenzimático (ELISA), teste de imunofluorescência de anticorpos (RIFI), reação em cadeia da polimerase convencional e quantitativa (cPCR e qPCR). Os valores de positividade obtidos com os testes sorológicos foram 71,4% (127/178), 70,2% (125/178) e 50,6% (90/178) com IC, ELISA e RIFI, respectivamente. E com 38,8% (69/178) dos cães mostraram-se simultaneamente positivos aos três testes. Os valores de positividade obtidos por cPCR e qPCR foram 20,2% (36/178) e 38,8% (69/178), respectivamente. E com 11,8% (21/178) dos cães foram positivos em ambos os testes moleculares. No geral, 87,1% (155/178) foram positivos para anticorpos anti-Leishmania spp. e/ou material genético de Leishmania spp. A positividade a um ou mais testes foi estatisticamente associada à linfonodomegalia, lesões cutâneas, linfocitose, anemia e hiperproteinemia. Os resultados do estudo revelam um alto nível de exposição à Leishmania spp. em cães errantes em uma área de transmissão intensa de leishmaniose visceral humana, sugerindo que eles podem desempenhar um papel como reservatórios no ciclo de transmissão dessa zoonose.

Assessment of a Brazilian public policy intervention to address schistosomiasis in Pernambuco state: the SANAR program, 2011-2014.

BACKGROUND: Brazil is an endemic country for schistosomiasis in the Latin American and Caribbean countries. Pernambuco is a higher-endemic Brazilian state among the 19 states reporting the disease in the country; schistosomiasis affects 102 (55%) of its 185 municipalities. Our objective was to evaluate the effectiveness of the treatment cycles of the SANAR Program (Plan to Reduce and Eliminate Neglected Diseases) in Pernambuco State in Northeast Brazil. METHODS: A cross-sectional population-based study was conducted in 2014 via a household survey in 117 hyperendemic locations in the state of Pernambuco. We compared the schistosomiasis prevalence rates in hyperendemic locations, aggregated by geographical region, before and after the intervention. The dependent variable was a positive stool test result by the Kato-Katz method, and the main exposure variable was the number of treatment cycles (one/two). The covariables were the regions of the state and socioenvironmental, socioeconomic, demographic and behavioral characteristics. RESULTS: In all, 12,969 individuals were interviewed, 8932 of whom had stool tests. Of these, 4969 (55.6%) underwent two cycles of collective treatment. Changes in the environmental conditions since 2011 were minimal. Comparison before (2011) and after (2014) treatment showed an average schistosomiasis prevalence of 18.6%, decreasing to 4.1% and 2.0% in locations with one and two treatment cycles, respectively. In 2014, the highest schistosomiasis prevalence was found in the forest area (2.8%), while the lowest was found in the northern region (1.2%) of the state. The adjusted analysis showed a lower occurrence of schistosomiasis in individuals living in areas with two treatment cycles than in individuals from areas with just one cycle (PR 0.65, 95% CI: 0.47-0.89). CONCLUSIONS: The political decision made in Pernambuco to implement the SANAR Program in 2011 greatly impacted the burden of schistosomiasis. This program was effective in reducing the occurrence of schistosomiasis in hyperendemic areas in Pernambuco, with a stronger response in areas with two cycles of collective treatment.