Spatial–temporal pattern of cutaneous leishmaniasis in Brazil

Abstract

Background Cutaneous leishmaniasis (CL) is a vector-borne disease classified by the World Health Organization as one of the most neglected tropical diseases. Brazil has the highest incidence of CL in America and is one of the ten countries in the world with the highest number of cases. Understanding the spatiotemporal dynamics of CL is essential to provide guidelines for public health policies in Brazil. In the present study we used a spatial and temporal statistical approach to evaluate the dynamics of CL in Brazil. Methods We used data of cutaneous leishmaniasis cases provided by the Ministry of Health of Brazil from 2001 to 2017. We calculated incidence rates and used the Mann–Kendall trend test to evaluate the temporal trend of CL in each municipality. In addition, we used Kuldorff scan method to identify spatiotemporal clusters and emerging hotspots test to evaluate hotspot areas and their temporal trends. Results We found a general decrease in the number of CL cases in Brazil (from 15.3 to 8.4 cases per 100 000 habitants), although 3.2% of municipalities still have an increasing tendency of CL incidence and 72.5% showed no tendency at all. The scan analysis identified a primary cluster in northern and central regions and 21 secondary clusters located mainly in south and southeast regions. The emerging hotspots analysis detected a high spatial and temporal variability of hotspots inside the main cluster area, diminishing hotspots in eastern Amazon and permanent, emerging, and new hotspots in the states of Amapá and parts of Pará, Roraima, Acre and Mato Grosso. The central coast the state of Bahia is one of the most critical areas due to the detection of a cluster of the highest rank in a secondary cluster, and because it is the only area identified as an intensifying hotspot. Conclusions Using a combination of statistical methods we were able to detect areas of higher incidence of CL and understand how it changed over time. We suggest that these areas, especially those identified as permanent, new, emerging and intensifying hotspots, should be targeted for future research, surveillance, and implementation of vector control measures. Graphic abstract

Temporal patterns, spatial risks, and characteristics of tegumentary leishmaniasis in Brazil in the first twenty years of the 21st Century

“…Despite the overall reduction of TL incidence in all regions of Brazil, a number of localities with increased rates have still been identified, and new cases have emerged in some municipalities that had no previous notifications [ 52 ]. From a broader viewpoint, the results presented herein demonstrate that the states of Minas Gerais and, to a lesser extent, Tocantins, Rio de Janeiro and Espírito Santo have seen increased numbers of notifications in recent years.…”

“…However, significant concentrations of cases and high incidence rates of TL are notorious in an area known officially as Brazil’s Legal Amazon [ 57 ], which encompasses the seven states of the North region together with Mato Grosso (Midwest) and Maranhão (Northeast), and also in the state of Bahia (Northeast). These areas presented the highest risk of occurrence of the disease throughout the target period, and this may be attributed to various factors including the vast extension of forest cover, the wide diversity of TL reservoirs and climatic conditions that are appropriate for the development of vectors, all of which favor the maintenance of the TL transmission cycle [ 52 ]. These areas, along with those located in the Southeast region exhibiting an increased trend of the disease, should be prioritized with respect to prevention, control, timely diagnosis and adequate treatment [ 28 , 58 ].…”

“…The present study employed secondary data and is, therefore, subject to limitations relating to the quality of the recorded information. The SINAN database consolidates data on notifiable diseases from all over Brazil [ 52 ], but the system has a number of deficiencies relating, in particular, to the high proportions of missing data for some variables and differences between regions regarding the completion of the notification forms. In addition, it is possible that the chance of identifying positive cases is lower in regions where TL is uncommon and healthcare professionals are less well acquainted with the disease [ 4 ].…”

Development and psychometric assessment of cutaneous leishmaniasis prevention behaviors questionnaire in adolescent female students: Application of integration of cultural model and extended parallel process model

“…Cutaneous Leishmaniasis (CL), as the most prevalent type of leishmaniasis, is an important public health issue in at least 83 countries, including Iran [1]. The cause of this disease is a protozoan parasite transmitted by sandfly bites [2].…”

Phylogenetic and biogeographical traits predict unrecognized hosts of zoonotic leishmaniasis

“…In the Americas, leishmaniasis cases occur from the southern United States to Argentina, including the Caribbean, with an estimated 58,500 new cases each year (Figure 1; PAHO, 2022). Further, incidence is rapidly shifting in geographic extent with land-use and climate change (3)(4)(5)(6)(7). For instance, hot spots of leishmaniasis have significantly expanded throughout Costa Rica in the last two decades, in concert with agricultural intensification, deforestation, and reforestation (4).…”