Burden of schistosomiasis-related mortality in Brazil: epidemiological patterns and spatial–temporal distribution, 2003–2018

Abstract

Objective: To characterise the epidemiological patterns and the spatial–temporal distribution of schistosomiasis-related mortality in Brazil from 2003 to 2018. Methods: A national population-based ecological study that used official data from the Mortality Information System. The data included all deaths recorded in Brazil from 2003 to 2018 in which schistosomiasis was mentioned in the death certificate as an underlying or associated cause of death (multiple causes). The municipalities of residence were used as units of geographic analysis, and standardised and smoothed mortality rates (per 100 000 inhabitants) were calculated using the local empirical Bayes method. Spatial autocorrelation was evaluated using global and local Moran indexes. To analyse the spatial dependence, the Getis-Ord G and Gi* statistics were used. Results: During the study period, 18 421 113 deaths were recorded in Brazil. Schistosomiasis was mentioned in 11 487 deaths (proportional mortality: 0.06%); for 8141 deaths (70.87%), it was listed as the underlying cause, and for 3346 deaths (29.13%), it was listed as an associated cause. The mean mortality rate was 0.38 deaths/100 000 inhabitants. Individuals ≥ 70 years of age (RR: 115.34, 95% CI: 68.56–194.03) and residents in the Northeast region (RR: 10.81, 95% CI: 5.95–19.66) presented higher risks related to schistosomiasis. Municipalities with high mortality rates were identified in all regions, and high-risk clusters were found in municipalities located in the Northeast and Southeast regions of the country. Conclusions: Schistosomiasis remains an important cause of death in persistently endemic areas in Brazil, particularly in those with a high prevalence of the disease and a marked parasite load.