Temporal trends in leptospirosis incidence and association with climatic and environmental factors in the state of Santa Catarina, Brazil. / Tendência temporal da leptospirose e sua associação com variáveis climáticas e ambientais em Santa Catarina, Brasil.

Leptospirosis is a zoonosis with epidemic potential, especially after heavy rainfall causing river, urban and flash floods. Certain features of Santa Catarina's coastal region influence these processes. Using negative binomial regression, we investigated trends in the incidence of leptospirosis in the six municipalities with the highest epidemic peaks between 2000 and 2015 and the climatic and environmental variables associated with the occurrence of the disease. Incidence was highest in 2008 and 2011, and peaks occurred in the same month or month after disasters. Incidence showed a strong seasonal trend, being higher in summer months. There was a decrease trend in incidence across the six municipalities (3.21% per year). The climatic and environmental factors that showed the strongest associations were number of rainy days, maximum temperature, presence of flash floods, and river flooding. The impact of these variables varied across the municipalities. Significant interactions were found, indicating that the effect of river flooding on incidence is not the same across all municipalities and differences in incidence between municipalities depend on the occurrence of river flooding.

A leptospirose é uma zoonose que apresenta potencial epidêmico, principalmente após fortes chuvas que acarretam inundações, alagamentos e enxurradas. Algumas características da região costeira de Santa Catarina, localizada no Sul do Brasil, influenciam nesses processos. Portanto, a partir do estudo da leptospirose nos seis municípios do estado com as maiores incidências e picos epidêmicos de 2000 a 2015, buscou-se conhecer a tendência dessa doença e as variáveis climáticas e ambientais associadas à sua ocorrência, ajustando dois modelos com resposta binomial negativa. As maiores incidências foram encontradas em 2008 e 2011, com picos no mesmo mês ou no posterior aos eventos de desastres. A incidência apresentou forte comportamento sazonal, sendo maior nos meses do verão. Observou-se tendência de queda na incidência dos municípios estudados, estimada em 3,21% ao ano. Os fatores climáticos e ambientais mais fortemente associados foram o número de dias de chuva, a temperatura máxima e a presença de enxurrada e de inundação, com diferentes impactos entre os municípios. Houve interações significativas, indicando que o efeito de inundações na incidência não é o mesmo em todos os municípios e que as diferenças nas incidências entre os municípios dependem da ocorrência ou não de inundações.

Tendência temporal da leptospirose e sua associação com variáveis climáticas e ambientais em Santa Catarina, Brasil / Temporal trends in leptospirosis incidence and association with climatic and environmental factors in the state of Santa Catarina, Brazil

Resumo A leptospirose é uma zoonose que apresenta potencial epidêmico, principalmente após fortes chuvas que acarretam inundações, alagamentos e enxurradas. Algumas características da região costeira de Santa Catarina, localizada no Sul do Brasil, influenciam nesses processos. Portanto, a partir do estudo da leptospirose nos seis municípios do estado com as maiores incidências e picos epidêmicos de 2000 a 2015, buscou-se conhecer a tendência dessa doença e as variáveis climáticas e ambientais associadas à sua ocorrência, ajustando dois modelos com resposta binomial negativa. As maiores incidências foram encontradas em 2008 e 2011, com picos no mesmo mês ou no posterior aos eventos de desastres. A incidência apresentou forte comportamento sazonal, sendo maior nos meses do verão. Observou-se tendência de queda na incidência dos municípios estudados, estimada em 3,21% ao ano. Os fatores climáticos e ambientais mais fortemente associados foram o número de dias de chuva, a temperatura máxima e a presença de enxurrada e de inundação, com diferentes impactos entre os municípios. Houve interações significativas, indicando que o efeito de inundações na incidência não é o mesmo em todos os municípios e que as diferenças nas incidências entre os municípios dependem da ocorrência ou não de inundações.

Abstract Leptospirosis is a zoonosis with epidemic potential, especially after heavy rainfall causing river, urban and flash floods. Certain features of Santa Catarina's coastal region influence these processes. Using negative binomial regression, we investigated trends in the incidence of leptospirosis in the six municipalities with the highest epidemic peaks between 2000 and 2015 and the climatic and environmental variables associated with the occurrence of the disease. Incidence was highest in 2008 and 2011, and peaks occurred in the same month or month after disasters. Incidence showed a strong seasonal trend, being higher in summer months. There was a decrease trend in incidence across the six municipalities (3.21% per year). The climatic and environmental factors that showed the strongest associations were number of rainy days, maximum temperature, presence of flash floods, and river flooding. The impact of these variables varied across the municipalities. Significant interactions were found, indicating that the effect of river flooding on incidence is not the same across all municipalities and differences in incidence between municipalities depend on the occurrence of river flooding.

Spatial analysis and factors associated with leptospirosis in Santa Catarina, Brazil, 2001-2015.

INTRODUCTION: Leptospirosis is an endemic disease in Brazil that can become an epidemic during the rainy season resulting from floods in areas susceptible to natural disasters. These areas are widespread in Santa Catarina, particularly in the coastal region. Therefore, the objective of this study was to identify environmental, climatic, and demographic factors associated with the incidence of leptospirosis in the municipalities of Santa Catarina from 2001 to 2015, taking into account possible spatial dependence. METHODS: This was an ecological study aggregated by municipality. To evaluate the association between the incidence of leptospirosis and the factors under study (temperature, altitude, occurrence of natural disasters, etc.) while taking into account spatial dependence, linear regression models and models with global spatial error were used. RESULTS: Lower altitudes, higher temperatures, and areas of natural disaster risk in the municipality contributed the most to explaining the variability in the incidence rate. After taking spatial dependence into account, only the minimum altitude variable remained significant. The regions of lower altitude, where the highest rates of leptospirosis were recorded, corresponded to the eastern portion of the state near the coastal region, where floods, urban floods, and overflows are common occurrences. No associations were found concerning demographic factors. CONCLUSIONS: The incidence of leptospirosis in Santa Catarina was associated with environmental factors, particularly low altitude, even when considering the spatial dependence structure present in the data. The spatial error model allowed for adequate modeling of spatial autocorrelation.

Correlation between climate data and land altitude for Fasciola hepatica infection in cattle in Santa Catarina, Brazil.

Fascioliasis is a food-borne parasitic disease that affects a range of animals, including humans caused by Fasciola hepatica. The present study aimed to determine the spatial distribution of bovine fasciolosis and to assess the correlation between the high Positivity Index (PI) and climate data and land altitude, from 2004 to 2008 and 2010 in Santa Catarina (SC), Brazil. Condemned livers of slaughtered animals were obtained from 198 out of 293 municipalities and from 518.635 animals, exclusively from SC. There was a statistically significant difference (P < 0.001) between the prevalence of F. hepatica and land altitude ( ρ ^ s = -0.43). The highest PI (above 10.1%) was observed in cities at 500 to 600 m (P < 0.01; ρ ^ s = -0.47) of altitude. There was no correlation between fascioliasis and rainfall in SC. It was determined that weather conditions in the past decade did not impose any limitation to the occurrence of the parasite, making it a disease of permanent clinical importance. These findings are essential to regions with similar geographical and climate conditions (i.e. altitude), when considering long-term control measurements, where animals and humans can be infected.

Leptospirosis and its spatial and temporal relations with natural disasters in six municipalities of Santa Catarina, Brazil, from 2000 to 2016.

Leptospirosis is a serious bacterial infection that occurs worldwide, with fatality rate of up to 40% in the most severe cases. The number of cases peaks during the rainy season and may reach epidemic proportions in the event of flooding. It is possible that people living in areas affected by natural disasters are at greater risk of contracting the disease. The aim of this study was to identify clusters of relatively higher risk for leptospirosis occurrence, both in space and time, in six municipalities of Santa Catarina, Brazil, which had the highest incidence of the disease between 2000 and 2016, and to evaluate if these clusters coincide with the occurrence of natural disasters. The cases were geocoded with the geographic coordinates of patients' home addresses, and the analysis was performed using SaTScan software. The areas mapped as being at risk for hydrological and mass movements were compared with the locations of detected leptospirosis clusters. The disease was more common in men and in the age group from 15 to 69 years. In the scan statistics performed, only space-time showed significant results. Clusters were detected in all municipalities in 2008, when natural disasters preceded by heavy rainfall occurred. One of the municipalities also had clusters in 2011. In these clusters, most of the cases lived in urban areas and areas at risk for experiencing natural disasters. The interaction between time (time of disaster occurrence) and space (areas at risk of experiencing natural disasters) were the determining factors affecting cluster formation.

Spatial analysis and factors associated with leptospirosis in Santa Catarina, Brazil, 2001-2015

Abstract INTRODUCTION: Leptospirosis is an endemic disease in Brazil that can become an epidemic during the rainy season resulting from floods in areas susceptible to natural disasters. These areas are widespread in Santa Catarina, particularly in the coastal region. Therefore, the objective of this study was to identify environmental, climatic, and demographic factors associated with the incidence of leptospirosis in the municipalities of Santa Catarina from 2001 to 2015, taking into account possible spatial dependence. METHODS: This was an ecological study aggregated by municipality. To evaluate the association between the incidence of leptospirosis and the factors under study (temperature, altitude, occurrence of natural disasters, etc.) while taking into account spatial dependence, linear regression models and models with global spatial error were used. RESULTS: Lower altitudes, higher temperatures, and areas of natural disaster risk in the municipality contributed the most to explaining the variability in the incidence rate. After taking spatial dependence into account, only the minimum altitude variable remained significant. The regions of lower altitude, where the highest rates of leptospirosis were recorded, corresponded to the eastern portion of the state near the coastal region, where floods, urban floods, and overflows are common occurrences. No associations were found concerning demographic factors. CONCLUSIONS The incidence of leptospirosis in Santa Catarina was associated with environmental factors, particularly low altitude, even when considering the spatial dependence structure present in the data. The spatial error model allowed for adequate modeling of spatial autocorrelation.

Correlation between climate data and land altitude for Fasciola hepatica infection in cattle in Santa Catarina, Brazil / Correlação entre clima e altitude para determinar a infecção de Fasciola hepatica em bovinos em Santa Catarina, Brasil

Abstract Fascioliasis is a food-borne parasitic disease that affects a range of animals, including humans caused by Fasciola hepatica. The present study aimed to determine the spatial distribution of bovine fasciolosis and to assess the correlation between the high Positivity Index (PI) and climate data and land altitude, from 2004 to 2008 and 2010 in Santa Catarina (SC), Brazil. Condemned livers of slaughtered animals were obtained from 198 out of 293 municipalities and from 518.635 animals, exclusively from SC. There was a statistically significant difference (P < 0.001) between the prevalence of F. hepatica and land altitude ( ρ ^ s = -0.43). The highest PI (above 10.1%) was observed in cities at 500 to 600 m (P < 0.01; ρ ^ s = -0.47) of altitude. There was no correlation between fascioliasis and rainfall in SC. It was determined that weather conditions in the past decade did not impose any limitation to the occurrence of the parasite, making it a disease of permanent clinical importance. These findings are essential to regions with similar geographical and climate conditions (i.e. altitude), when considering long-term control measurements, where animals and humans can be infected.

Resumo A fasciolose é uma doença parasitária que afeta uma gama de animais, incluindo humanos, causada por Fasciola hepatica no Brasil. Este estudo teve o objetivo de determinar a distribuição espacial da fasciolose e conferir a correlação do alto índice de positividade (PI), com os dados de clima e altitude, entre 2004 a 2008 e 2010 em Santa Catarina (SC), Brasil. Foram obtidos fígados em frigoríficos de SC, de 518.635 animais de 198 municípios, de um total de 293. Houve diferença estatística significativa (P < 0,001) entre a prevalência de F. hepatica e a altitude ( ρ ^ s = -0,43). O maior PI (acima de 10,1%) foi observado em municípios de 500 a 600 m (P < 0,01; ρ ^ s = -0,47) de altitude. Não foi observada correlação entre fígados parasitados e pluviosidade em SC. Foi observado que os dados climáticos na ultima década não apresentaram limitação para a ocorrência do parasito, fazendo com que o desafio clinico da infecção tenha sido permanente. Os dados são importantes para locais com condições geográficas e climáticas semelhantes (ex. altitude), para considerar medidas de controle a longo prazo, nas quais animais e humanos poderão ser infectados.

Análise espacial e temporal da ocorrência de leptospirose em Santa Catarina e sua relação com fatores climáticos e ambientais / Spatial and temporal analysis of leptospirosis occurrence in Santa Catarina and its relations with climatic and environmental factors

INTRODUÇÃO: A leptospirose é uma doença causada por bactérias do gênero Leptospira presente na urina de animais infectados. Essas bactérias, quando dispersas no ambiente, podem misturar-se com a água e provocar o contágio, uma vez que o homem entre em contato com essa água contaminada. Esta doença acarreta alto custo, limitações à vida dos infectados e alta letalidade. O excesso de chuvas e a ocorrência de desastres naturais hidrológicos podem favorecer surtos e epidemias. Santa Catarina é frequentemente acometido por desastres como deslizamentos de terra, inundações e enxurradas, sendo estes dois últimos responsáveis por 43% dos desastres mais recorrentes entre 1991 e 2012. OBJETIVO: Descrever a ocorrência da leptospirose no tempo, no espaço e no espaço-tempo, principalmente em situações de desastres naturais, e identificar fatores associados à esta ocorrência em Santa Catarina. METODOLOGIA: Foi realizado um estudo descritivo e ecológico, utilizando estatísticas de varredura e modelos de regressão, apresentados em três manuscritos. MANUSCRITO 1: Detecção de aglomerados de maior risco para a leptospirose, tanto no espaço quanto no tempo, em seis municípios do Estado, de 2000 a 2016. Os casos foram geocodificados com as coordenadas geográficas dos seus endereços residenciais e a análise foi feita no SaTScan. O local das áreas mapeadas como de risco hidrológico e de movimentos de massa foi comparado com os aglomerados detectados. Foram detectados aglomerados espaço-temporais em todos os municípios em 2008, quando ocorreram desastres naturais precedidos por grande volume de chuvas. A maioria dos casos residia em área urbana e de risco para desastres naturais. MANUSCRITO 2: Identificação de fatores ambientais, climáticos e demográficos associados à leptospirose nos municípios do Estado, no período de 2001 a 2015, levando em conta a dependência espacial. Foram utilizados modelos de regressão linear e modelos com efeitos espaciais globais. A altitude mínima, a temperatura máxima e a existência de área de risco no município foram as que mais contribuíram para explicar a variabilidade com a incidência. Após levar em conta a dependência espacial, apenas a variável altitude mínima se manteve significativa. As regiões de menor altitude apresentaram as maiores taxas, onde é frequente a ocorrência de enchentes, enxurradas e inundações. Não foram associados fatores demográficos. MANUSCRITO 3: Análise da tendência da leptospirose e dos fatores climáticos e ambientais associados, em seis municípios do Estado, de 2000 a 2015. Foram ajustados dois modelos com resposta Binomial Negativa, um para avaliar a tendência da incidência, e o outro para determinar os fatores associados. As maiores incidências foram em 2008 e 2011, com picos no mesmo mês ou no anterior de eventos de desastres, principalmente no verão, com tendência de queda estimada em 3,21% ao ano, em todos os municípios. Os fatores associados foram o número de dias de chuva, a temperatura máxima, a presença de inundação, que causou diferente impacto entre os municípios, e a presença de enxurrada. O efeito de inundações na incidência não foi o mesmo em todos os municípios e as diferenças nas incidências entre os municípios dependem da ocorrência ou não de inundações.

INTRODUCTION: Leptospirosis is a disease caused by the Leptospira bacteria, which are present in the urine of infected animals. These bacteria, when dispersed in the environment, can mix with water and cause contagion once man comes into contact with contaminated water. This disease entails high cost and leads to life limitations of the infected, with high fatality rate. Excessive rainfall and the occurrence of hydrological natural disasters can favor outbreaks and epidemics. Santa Catarina is often affected by disasters such as landslides, flooding and flashfloods, the latter two accounting for 43% of the most recurring disasters between 1991 and 2012. OBJECTIVE: To describe the occurrence of leptospirosis in time, space and space-time, especially in natural disaster situations, and identify factors associated with occurrence in Santa Catarina. METHODOLOGY: A descriptive and ecological study was performed using scan statistics and regression models. It is presented in three manuscripts. MANUSCRIPT 1: Detection of clusters of higher risk for leptospirosis, in both space and time, in six municipalities of Santa Catarina from 2000 to 2016. The cases were geocoded with the geographic coordinates of the patients' residential addresses, and the analysis was performed using SaTScan software. The areas mapped being at risk for hydrological disasters and mass movements were compared with the locations of the detected clusters. Spatiotemporal clusters were detected in all municipalities in 2008, when natural disasters preceded by heavy rainfall occurred. Most of the cases were in urban areas that were at risk for natural disasters. MANUSCRIPT 2: Identification of environmental, climatic and demographic factors associated with leptospirosis in the municipalities of the state, from 2001 to 2015, taking into account spatial dependence. Linear regression models and models with global spatial effects were used. The minimum altitude, the maximum temperature and the existence of risk area in the municipality contributed the most to explain the variability with the incidence. After taking into account spatial dependence, only the minimum altitude variable remained significant. The regions with the lowest altitude presented the highest rates, where floods, flashfloods and flooding frequently occur. No demographic factors were associated. MANUSCRIPT 3: Analysis of the trend of leptospirosis and associated climate and environmental factors in six municipalities of the state from 2000 to 2015. Two models with negative binomial response were adjusted, one to assess the trend of incidence, and the other to determine associated factors. The highest incidences were in 2008 and 2011, with peaks in the same or previous month of disaster events, especially in summer, with an estimated downward trend of 3.21% per year in all municipalities. Associated factors were number of rainy days, maximum temperature, flooding occurrence, which caused different impact among the municipalities, and flashflood occurrence. The effect of flooding on incidence was not the same in all municipalities and differences in incidence among municipalities depend on whether or not flooding occurs.

Assessing the risk of bovine fasciolosis using linear regression analysis for the state of Rio Grande do Sul, Brazil.

Fasciola hepatica is the causative agent of fasciolosis, a disease that triggers a chronic inflammatory process in the liver affecting mainly ruminants and other animals including humans. In Brazil, F. hepatica occurs in larger numbers in the most Southern state of Rio Grande do Sul. The objective of this study was to estimate areas at risk using an eight-year (2002-2010) time series of climatic and environmental variables that best relate to the disease using a linear regression method to municipalities in the state of Rio Grande do Sul. The positivity index of the disease, which is the rate of infected animal per slaughtered animal, was divided into three risk classes: low, medium and high. The accuracy of the known sample classification on the confusion matrix for the low, medium and high rates produced by the estimated model presented values between 39 and 88% depending of the year. The regression analysis showed the importance of the time-based data for the construction of the model, considering the two variables of the previous year of the event (positivity index and maximum temperature). The generated data is important for epidemiological and parasite control studies mainly because F. hepatica is an infection that can last from months to years.

Impactos de desastres socioambientais em saúde pública: estudos dos casos dos Estados de Santa Catarina em 2008 e Pernambuco em 2010 / /Impacts of socio-environmental disasters on public health: studies of scenarios in the Brazilian states of Santa Catarina in 2008 and Pernambuco in 2010 / /Impactos de los desastres socioambientales en la salud pública: estudio de los casos de los estados brasileños de Santa Catarina en 2008 y Pernambuco en 2010

Eventos como inundações e movimentos de massa podem provocar desastres, afetando amplamente a saúde pública brasileira. Além de mortes, traumas e lesões, podem ocorrer danificação de estações de tratamento de água, postos de saúde e hospitais, comprometimento de equipamentos e estoque de remédios, epidemias e proliferação de doenças, bem como danos psicossociais. Neste artigo, com o objetivo de identificar e analisar características pré e pós-impacto relacionadas à saúde pública, são estudados dois cenários: inundações ocorridas em Santa Catarina, em 2008, e em Pernambuco, em 2010. Procuramos analisar as condições socioambientais e de cobertura de serviços de saúde prévias e os danos pós-impacto em municípios que decretaram estado de calamidade pública. Para caracterizar a vulnerabilidade socioambiental, foram utilizados dados do Instituto Brasileiro de Geografia e Estatística (IBGE) do Serviço Geológico do Brasil (CPRM), da Secretaria Nacional de Proteção e Defesa Civil (Sedec) e do Sistema Único de Saúde (Datasus). Encontramos grandes diferenças entre os dois estados, principalmente nos indicadores sociais, mas os efeitos das inundações foram severos para ambos, incluindo maior número de óbitos em Santa Catarina, estado com alto índice de desenvolvimento humano e menores índices de pobreza. Estes resultados evidenciam a necessidade de inclusão do tema saúde pública em todas as etapas do gerenciamento do risco de desastres...

Events such as floods and landslides can cause disasters that affect Brazilian public health extensively. Impacts include traumas and injuries, damage to water treatment plants and hospitals, disruption of equipment and medicine supply, epidemics and the spread of diseases, as well as lasting psychosocial damage. In this article, we study disaster scenarios in municipalities from two Brazilian states that had declared a state of public calamity as a result of flooding - Santa Catarina (2008) and Pernambuco (2010). The object was to identify and analyze the impacts of these disasters on social and environmental conditions as well as on the coverage of public health. To this purpose, the before and after disaster situation in affected municipalities was analyzed. To characterize socio-environmental vulnerability, we used data from the Brazilian Institute of Geography and Statistics (IBGE), the Brazilian Geological Survey (CPRM), the National Protection and Civil Defense Secretariat (SEDEC) and the Health Ministry. Although there are expressive differences between the two investigated states, especially in regards to social indicators, both of them suffered strong impacts after floods. Despite a higher human development index and low levels of poverty, Santa Catarina suffered more deaths than Pernambuco. Altogether, results demonstrate the need to include public health issues in all steps of disaster risk management...

Influência da precipitação na qualidade da água do Rio Purus / Impacts of precipitation on the water quality of the Purus River

Os impactos da precipitação na qualidade da água ao longo do rio Purus, localizado no estado do Amazonas, foi investigado por meio de dados de precipitação, estimada por satélites, e informações sobre a temperatura da água, condutividade, pH, turbidez, oxigênio dissolvido e sólidos suspensos totais, adquiridas em quatro diferentes áreas ao longo do rio. Os resultados mostraram correlação negativa entre precipitação e turbidez e positiva entre precipitação e temperatura, condutividade, oxigênio dissolvido, sólidos suspensos totais e pH. O uso do solo, juntamente com o regime de precipitação, parecem ser os fatores principais que determinam a qualidade da água nos pontos de amostragem.

The impacts of precipitation on the water quality along the Purus River, located in the Brazilian State of the Amazonas, was investigated using data of precipitation estimated by satellite and information about water temperature, conductivity, pH, turbidity, dissolved oxygen and total suspended solids. The data were acquired in four different areas along the river. The results showed negative correlation between precipitation and turbidity. They also showed positive correlation between precipitation and temperature, conductivity, dissolved oxygen, total suspended solids and pH. The land use together with the rainfall regime seems to be the main sources of impact on the water quality around the sampling places.