OBJECTIVE:To analyze the spread of human American visceral leishmaniasis and identify the key municipalities for developing surveillance and control activities. METHODS:The area of the study was composed of the 316 municipalities in the state of Sao Paulo belonging to the fi ve health districts in which human American visceral leishmaniasis occurs, using data on autochthonous cases and deaths according to the reporting year and municipality in which the death occurred. The incidence, mortality and case fatality rates for each municipality and for the entire area were calculated. An empirical Bayes estimator was used to calculate the local Bayesian incidence and rates of mortality per municipality, and Kriging was used to visualize the spatial distribution of temperature and rainfall. RESULTS:A total of 73 municipalities with transmission of the disease were identifi ed. Human American visceral leishmaniasis was fi rst detected in areas with higher temperatures and lower rainfall, but it also spread in cooler and wetter areas. The expansion of human American visceral leishmaniasis occurred along a main axis of dissemination, from Northwest to Southeast, following the Marechal Rondon highway and the Bolivia-Brazil gas pipeline, and along a secondary axis that was derived from the main axis, which runs both North and South, following the highway network. Rates of incidence according to health district exhibit a peak, followed by a fall, except the Sao Jose do Rio Preto region. Higher concentrations of municipalities with high incidence and mortality rates were observed in the Araçatuba, Presidente Prudente and Marília health districts. CONCLUSIONS:This study indicates possible determinants of the spread of disease, including the Marechal Rondon highway and the construction of the Bolivia-Brazil gas pipeline. Climatic factors seemed to play no role in the spread. The use of spatial analysis techniques allowed the municipalities where cases and deaths are possibly underreported to be identifi ed, which indicated the municipalities which should be prioritized for the development of surveillance and control activities.

The control of American visceral leishmaniasis (AVL) is based on combating the vector and eliminating the domestic reservoir of the focus area - defined as 200 meters around human or canine cases. This paper discusses the use of spatial analysis techniques in the epidemiological surveillance of AVL in Araçatuba, São Paulo State, in order to propose a model for territorial epidemiological surveillance, reformulating current control strategies. The results showed that AVL transmission was not homogeneous; human cases were more frequent in areas with higher canine prevalence rates. Vector dispersion appeared to be restricted to a few houses, although it was not possible to model the vector density. In order to study the vector distribution and correlated covariates, a field study based on house sampling is being conducted. The results will aid the development of new spatial analysis tools and possibly redefine protocols and routines for the control of this endemic disease in urban areas.

OBJECTIVE Estimate the coverage of control measures of visceral leishmaniasis and relate them with the occurrence of human visceral leishmaniasis in endemic urban area.METHODS Cases of human and canine visceral leishmaniasis were considered as study population and evaluated by a serological survey conducted in Araçatuba, state São Paulo, from 2007 to 2015. The cases of human visceral leishmaniasis were geocoded by the address of the patients and the canine disease by the address of the dogs’ owners. The coverage of serological survey, euthanasia, and insecticide spraying was calculated, as well as the canine seroprevalence and the incidence rates of human visceral leishmaniasis. The relationship between human visceral leishmaniasis and control measures was evaluated, as well as the seroprevalence by comparing maps and by linear regression. The relationship between the canine and the human disease was also evaluated by the Ripley’s K function.RESULTS The incidence rates of human visceral leishmaniasis showed a period of decline (2007 to 2009) and a period of stability (2010 to 2015), a behavior similar to that of canine seroprevalence. In general, the coverage of control measures was low, and the non-association with the incidence of human visceral leishmaniasis can be a result of the period analyzed and of the small number of analyzed units (sectors of the Superintendence for the Control of Endemic Diseases). The distribution of human cases showed spatial dependence with the distribution of seropositive dogs from 2007 to 2009.CONCLUSIONS This study reaffirmed the relationship between the occurrence of the disease in humans and dogs, it verified a decrease in the rates of visceral leishmaniasis in Araçatuba over time, even at low coverage of control activities. However, further studies are needed to determine if factors beyond monitoring and control measures are involved in the reduction of incidences.

Introduction:In 1999, Birigui and Araçatuba were the fi rst municipalities in the State of São Paulo to present autochthonous cases of visceral leishmaniasis in humans (VLH). The aim of this study was to describe the temporal, spatial and spatiotemporal behaviors of VLH in Birigui. Methods: Secondary data were obtained from the Notifi able Diseases Information System from 1999 to 2012. The incidence, mortality and case fatality rates by sex and age were calculated. The cases of VLH were geocoded and grouped according to census tracts. Local empirical Bayesian incidence rates were calculated. The existence of spatial and spatiotemporal clusters was investigated using SaTScan software. Results: There were 156 confi rmed cases of autochthonous VLH. The incidence rate was higher in the 0-4-year-old children, and the mortality and case fatality rates were higher in people aged 60 years and older. The peaks of incidence occurred in 2006 and 2011. The Bayesian rates identifi ed the presence of VLH in all of the census tracts in the municipality; however, spatial and spatiotemporal clusters were found in the central area of the municipality. Conclusions: Birigui, located in the Araçatuba region, has recently experienced increasing numbers of VLH cases; this increase is contrary to the behavior observed over the entire region, which has shown a decreasing trend in the number of VLH cases. The observations that the highest incidence is in children 0-4 years old and the highest mortality is in people 60 years and older are in agreement with the expected patterns of VLH.

No abstract