Risk areas for Human Visceral Leishmaniosis 2007–2018: A temporal and spatial analysis in Ceará, Brazil

Abstract

Visceral leishmaniasis (VL) is considered as an important tropical disease because it rapidly spreads across a wide geographical area. This study aimed to analyse the temporal and spatial patterns of incidence, mortality and case fatality rates due to human VL in Ceará, Brazil, from 2007 to 2018. This is an ecological study involving time series and spatial analyses, and data were obtained from human VL notifications.Temporal trend analysis was carried out using the Joinpoint Regression Program. SaTScan 9.6 was used for conducting spatial analyses, and ArcMap 9.2 was used for building maps. There were 6,066 incident cases and 516 deaths due to human VL.

Diagnosis of visceral leishmaniasis in Ceará state, Brazil: A flow analysis of cases between 2007 and 2021

“…The intensification of the flow of VL cases diagnosed in Fortaleza, one of the largest centres for VL diagnosis, both for patients from other municipalities, as well as for those diagnosed in the same municipality of residence, may be related to population density, continuous provision of training for health professionals, intersectoral actions between sanitary surveillance and health and availability of health services within the scope of the SUS [22,23]. The public health network in Fortaleza is composed of 92 emergency care units, one centre of medical specialties, a hospital of high complexity, and 10 hospitals of medium complexity [24,25].…”

“…The southern region of Cear a represents an important centre of fruit production, which may contribute to the high number of VL cases. The geography of these areas is characterised by plateaus and valleys, with temperatures ranging from 20 C on the top of the mountains, to up to 28 C in the hottest backlands, precipitation less than 500 mm, and predominance of caatinga vegetation and fauna diversified by backlands and mountains, which favours the reproduction of phlebotomine sandflies [5,23,27,28].…”

Hierarchical spatiotemporal modeling of human visceral leishmaniasis in Rio Grande do Norte, Brazil

“…Specifically, we see that the southwest municipalities are highly likely to have risk of VL more than double the expectation. West Potiguar borders the states of Ceará and Paraíba, who have also experienced increasing incidence rates of VL over time, respectively [ 6 , 8 ]. The exceedance probabilities of relative risk greater than two for the Central and Agreste Potiguar regions range between 0% and 80% across time, with a few northern municipalities showing high exceedance probabilities during the earlier years of this study.…”

“…Additionally, previous studies [ 3 , 4 , 8 ] analyze incidence of VL across space, using Moran’s I, and over time via segmented or joinpoint regression. Exploratory spatial techniques like Moran’s I can help quantify the presence of spatial correlation.…”