Mapping the risk for transmission of urban schistosomiasis in the Brazilian Northeast.

This is an analysis of the risk of schistosomiasis transmission in the city of Recife in the Northeast of Brazil based on the number of schistosomiasis cases (Schistosoma mansoni) registered for the period 2007-2017 together with data resulting from active search of breeding sites of the Biomphalaria snail intermediate host. The analyses were performed using Kernel Density Estimation (KDE), SaTScan and Map Algebra methodology using human socio-demographic data and biotic and abiotic data from the snail breeding sites. Investigating 44 breeding sites resulted in a total of 3.800 snails, 31.8% of which were positive for S. mansoni DNA. These data were considered in relation to total of 652 schistosomiasis cases. The KDE showed two high-risk and two medium-risk clusters, while three significant clusters were identified by SaTScan. Combining these data with the Map Algebra methodology showed that all high-risk neighbourhoods had breeding sites with snails positive for S. mansoni. It was concluded that schistosomiasis transmission cannot be controlled without basic sanitation and sewage management in the presence of Biomphalaria snails. The technique of Map Algebra was found to be fundamental for the analysis and demonstration of areas with a high probability of schistosomiasis transmission.

Morbidity of mansoni schistosomiasis in Pernambuco-Brazil: Analysis on the temporal evolution of deaths, hospital admissions and severe clinical forms (1999-2014).

BACKGROUND: Current scientific information reported that due to successive treatments of schistosomiasis cases in endemic areas of Brazil in the last 30 years, there has been a decrease in severe clinical form (hepatosplenic) and mortality from upper gastrointestinal bleeding due to this disease. Against this information, literature data show that the state of Pernambuco presents significant percentage of deaths and hospitalizations due to schistosomiasis, and occurrence of severe clinical forms as schistosomiasis myeloradiculopathy and persistence of localities with high parasite loads. This scenario justified this research which seeking to update the morbidity and mortality of schistosomiasis in Pernambuco. OBJECTIVE: To conduct a temporal analysis on the evolution of deaths, hospital admissions and severe forms of Manson's schistosomiasis over the last 16 years in Pernambuco, Brazil. METHODS: It was performed a gathering secondary data on schistosomiasis, from healthcare information systems and from the records of Hospital das Clínicas, Federal University of Pernambuco (HC-UFPE), covering the period from 1999 to 2014. RESULTS: From 1999 to 2013 were registred 2578 deaths due to schistosomiasis and between 2008 and 2014 were recorded 473 hospitalizations for this disease. Among 1999-2014 were identified 1943 cases of schistosomiasis treated at the Hospital das Clínicas of Pernambuco. Among these cases, 72.6% (n. 1411) of the individuals presented the hepatosplenic clinical form (HE), 60.8% (n. 858) were at the age group 30-59 years (adults) and 58% were female. Among the HE cases, 4.6% (n. 58) had ascites, 43.2% (n. 556) had upper gastrointestinal bleeding and 39.1% (n. 489) had collateral circulation. The pattern of fibrosis in the liver E/EC (advanced fibrosis) and F/FC (very advanced fibrosis) occurred in 65.5% (n. 793) of cases. Between 1999-2014 the evolution curve of severe clinical forms of schistosomiasis remained stable, showing a tendency to decline from 2012. CONCLUSION: When compared to other states of Brazil, Pernambuco shows high numbers of deaths and hospital admissions due to schistosomiasis. The actions of the Schistosomiasis Control Program (PCE) have been developed in a disintegrated, disjointed and discontinuous way, which may explain the magnitude of deaths, hospitalizations and severe forms of the disease in Pernambuco, showing a lack of control and the maintenance of severe frame morbidity of schistosomiasis in this state.