''Inserting the etonorgestrel implant into the thigh: A case report''.

Etonorgestrel implant is inserted on the inner surface of the non-dominant medial upper arm in women, over the triceps area. However, this case report aims to describe an alternative insertion site for etonorgestrel implant - the medial side of the thigh - in nephropathic patients with arteriovenous fistulas undergoing hemodialysis.

Five-year Contraceptive Use of 52-mg Levonorgestrel Releasing Intrauterine System in Young Women, Menstrual Patterns, and New Contraceptive Choice.

OBJECTIVE: To evaluate the continuation rates of the 52-mg levonorgestrel-releasing intrauterine system (LNG-IUS) during the first 5 years of use, reasons for its discontinuation, bleeding patterns, and new contraceptive choice after the 5th year, in adolescents and young women. METHODS: The present study was a 5-year prospective cohort conducted in a Family Planning Service of a tertiary hospital in Brazil. We selected 100 healthy women between 15 and 24 years old who used 52-mg LNG-IUS for contraception. The clinical follow-up of these women took place from June 2017 to December 2022. The study evaluated the continuation rates of the method, reasons for its discontinuation, bleeding patterns, and new contraceptive choice after the 5th year. Continuous data were reported as mean ± standard deviation (SD) and range (minimum-maximum). Categorical variables were described as percentages. RESULTS: The continuation rates of LNG-IUS were 89.1% (82/92), 82.9% (72/87), 75.3% (64/85), 70.5% (60/85), and 64.2% (54/84) in the 1st, 2nd, 3rd, 4th, and 5th years of use, respectively. The main reason for discontinuation was acne (11/30). Amenorrhea rates were 50, 54.1, 39, 35.7, and 51.8% at 12, 24, 36, 48, and 60 months, respectively. All patients who completed the study and needed contraception after the 5th year opted for long-acting contraceptive methods (LARC). CONCLUSION: The LNG-IUS showed high continuation rates in adolescents and young women in the first 5 years of use. Most patients who completed the study chose a LARC method after the 5th year.

OBJETIVO: Avaliar as taxas de continuação do sistema intrauterino liberador de levonorgestrel (SIU-LNG) 52 mg durante os primeiros 5 anos de uso, razões de sua descontinuação, padrões de sangramento e nova escolha contraceptiva após o 5° ano, em adolescentes e mulheres jovens. MéTODOS: O estudo foi uma coorte prospectiva de 5 anos realizada em um Serviço de Planejamento Familiar de um hospital terciário no Brasil. Selecionamos 100 mulheres saudáveis entre 15 e 24 anos que usaram o SIU-LNG 52 mg para contracepção. O acompanhamento clínico dessas mulheres ocorreu de junho de 2017 a dezembro de 2022. O estudo avaliou as taxas de continuação do método, razões de sua descontinuação, padrões de sangramento e nova escolha contraceptiva após o 5° ano. Os dados contínuos foram relatados como média ± DP e intervalo (mínimo-máximo). As variáveis categóricas foram descritas como porcentagens. RESULTADOS: As taxas de continuação do SIU-LNG foram 89,1% (82/92), 82,9% (72/87), 75,3% (64/85), 70,5% (60/85) e 64,2% (54/84) no 1°, 2°, 3°, 4° e 5° anos de uso, respectivamente. O principal motivo de descontinuação foi a acne (11/30). As taxas de amenorreia foram de 50, 54,1, 39, 35,7 e 51,8% aos 12, 24, 36, 48 e 60 meses, respectivamente. Todas as pacientes que completaram o estudo e necessitaram de contracepção após o 5° ano optaram por métodos contraceptivos de longa duração (LARC). CONCLUSãO: O SIU-LNG apresentou altas taxas de continuação em adolescentes e mulheres jovens nos primeiros 5 anos de uso. A maioria das pacientes que completou o estudo escolheu um método LARC após o 5° ano.

Dengue virus serotype 2 genotype III evolution during the 2019 outbreak in Mato Grosso, Midwestern Brazil.

DENV-2 was the main responsible for a 70% increase in dengue incidence in Brazil during 2019. That year, our metagenomic study by Illumina NextSeq on serum samples from acute febrile patients (n = 92) with suspected arbovirus infection, sampled in 22 cities of the state of Mato Grosso (MT), in the middle west of Brazil, revealed eight complete genomes and two near-complete sequences of DENV-2 genotype III, one Human parvovirus B19 genotype I (5,391 nt) and one Coxsackievirus A6 lineage D (4,514 nt). These DENV-2 sequences share the aminoacidic identities of BR4 lineage on E protein domains I, II and III, and were included in a clade with sequences of the same lineage circulating in the southeast of Brazil in the same year. Nevertheless, 11/34 non-synonymous mutations are unique to three strains inthis study, distributed in the E (n = 6), NS3 (n = 2) and NS5 (n = 3) proteins. Other 14 aa changes on C (n = 1), E (n = 3), NS1 (n = 2), NS2A (n = 1) and NS5 (n = 7) were first reported in a genotype III lineage, having been already reported only in other DENV-2 genotypes. All 10 sequences have mutations in the NS5 protein (14 different aa changes). Nine E protein aa changes found in two sequences, six of which are unique, are in the ectodomain; where the E:M272T change is on the hinge of the E protein at domain II, in a region critical for the anchoring to the host cell receptor. The NS5:G81R mutation, in the methyltransferase domain, was found in one strain of this study. Altogether, these data points to an important evolution of DENV-2 genotype III lineage BR4 during this outbreak in 2019 in MT. Genomic surveillance is essential to detect virus etiology and evolution, possibly related to immune evasion and viral fitness changes leading to future novel outbreaks.

Hepatitis B vaccination coverage and serological status among health care workers exposed to occupational biological hazards.

Introduction: Health care workers are often exposed to hepatitis B infection during the course of their professional roles. Objectives: To analyze the hepatitis B vaccination coverage and the presence of antibodies against hepatitis B among health care professionals who were exposed to contaminated biological material at a hospital complex. Methods: This descriptive, retrospective, and quantitative study is based on the analysis of accident notification form data (n = 2,466) from a hospital complex covering the period between 2011 and 2020. Results: Among the affected individuals, women (69.5%), medical residents (35.7%), and nursing staff (25.5%) accounted for the highest proportion of hazards. Regarding vaccination status, 98% of the health care professionals reported being fully immunized, and antibodies were detected in 90.9% of the participants. Percutaneous exposure (76.4%) was the most prevalent type of hazard, with blood being the most commonly involved material (79.4%). Conclusions: The findings show that despite the risks of Hepatitis B contamination associated with the incidents, the professionals were protected due to the high vaccination coverage and evidence of immunity.

Introdução: Os trabalhadores da saúde estão constantemente expostos ao vírus da hepatite B durante a atividade laboral. Objetivos: Analisar a cobertura vacinal contra a hepatite B e a presença do anticorpo contra o antígeno de superfície da hepatite B (anti-HBs) entre profissionais e estudantes da área da saúde que sofreram acidente com material biológico em um complexo hospitalar universitário. Métodos: Tratou-se de um estudo descritivo, retrospectivo e quantitativo, baseado na análise dos dados das fichas de notificação (n = 2.466) dos acidentes ocorridos no período de 2011 a 2020. Resultados: As mulheres (69,5%), os residentes de medicina (35,7%) e os técnicos e auxiliares de enfermagem (25,5%) foram os que mais se acidentaram. Quanto ao estado vacinal dos trabalhadores de saúde para hepatite B, 98% declararam ter o esquema vacinal completo, e a presença de anti-HBs reagente foi detectada em 90,9%. Quanto às características dos acidentes, houve prevalência de exposição percutânea (76,4%), e sangue foi o material orgânico mais comumente envolvido (79,4%). Conclusões: Os achados demonstram que, apesar do risco de contaminação para o vírus da hepatite B associado a acidentes no ambiente de trabalho, os profissionais estavam protegidos devido à elevada cobertura vacinal e à imunidade comprovada.

Consumption of food groups and associated factors among children aged 6 to 23 months.

OBJECTIVE: To assess the consumption of food groups among children aged 6 to 23 months in day care centers and at home and its associated factors. METHODS: This is a population-based cross-sectional study conducted with children from nursery schools in Guaratuba, Paraná. Parents answered a socioeconomic and demographic questionnaire. Food consumption was assessed by directly weighing the meals offered at the day care center. At home, parents filled an estimated food record. The reported foods were classified into seven food groups. Minimum dietary diversity was calculated by the proportion of children who consumed foods from four or more groups. Data were analyzed by simple and multiple logistic regression, presented as odds ratios. RESULTS: A total of 213 children participated in this study. The average number of food groups consumed was 4.2±1.0 at home and 4.2±1.2 in day care centers. At the day care center, all children consumed grains, roots, and tubers, while at home, this rate was 99.1%. The egg group was the least consumed both at day care (6.6%) and at home (2.8%). At home, more than 60% of children consumed sweets and sugar-sweetened beverages. Children aged 12 to 23 months were more likely to consume milk and dairy products, as well as flesh foods. Higher income was associated with the consumption of legumes, and older maternal age with the consumption of fruits and vegetables. CONCLUSIONS: At home, children had a predominantly dairy-based diet and a high intake of ultra-processed foods. In day care centers, the consumption of healthy foods was higher, indicating the need for families to participate in the formation of healthy eating habits.

Genomic epidemiology reveals the impact of national and international restrictions measures on the SARS-CoV-2 epidemic in Brazil.

Brazil has experienced some of the highest numbers of COVID-19 cases and deaths globally and from May 2021 made Latin America a pandemic epicenter. Although SARS-CoV-2 established sustained transmission in Brazil early in the pandemic, important gaps remain in our understanding of virus transmission dynamics at the national scale. Here, we describe the genomic epidemiology of SARS-CoV-2 using near-full genomes sampled from 27 Brazilian states and a bordering country - Paraguay. We show that the early stage of the pandemic in Brazil was characterised by the co-circulation of multiple viral lineages, linked to multiple importations predominantly from Europe, and subsequently characterized by large local transmission clusters. As the epidemic progressed under an absence of effective restriction measures, there was a local emergence and onward international spread of Variants of Concern (VOC) and Variants Under Monitoring (VUM), including Gamma (P.1) and Zeta (P.2). In addition, we provide a preliminary genomic overview of the epidemic in Paraguay, showing evidence of importation from Brazil. These data reinforce the usefulness and need for the implementation of widespread genomic surveillance in South America as a toolkit for pandemic monitoring that provides a means to follow the real-time spread of emerging SARS-CoV-2 variants with possible implications for public health and immunization strategies.

Anti-Inflammatory Potential of the Oleoresin from the Amazonian Tree Copaifera reticulata with an Unusual Chemical Composition in Rats.

Copaifera reticulata Ducke is a popularly known species known as copaíba that is widely spread throughout the Amazon region. The tree yields an oleoresin which is extensively used in local traditional medicine mainly as an anti-inflammatory and antinociceptive agent. The aim of the present study was to assess the anti-inflammatory potential of this oleoresin obtained from a national forest in the central Amazon which presented an unusual chemical composition. The chemical composition of volatile compounds of oleoresin was analyzed by gas chromatography-mass spectrometry. The acute toxicity assay was performed with a single dose of 2000 mg/kg. The anti-inflammatory potential was evaluated by carrageenan-induced paw edema and air pouch assays using four different C. reticulata oleoresin concentrations (10, 100, and 400 mg/kg). The exudate was evaluated for nitrite concentration through the colorimetric method and for TNF-α, IL-1ß, and PGE2 by ELISA. C. reticulata oleoresin collected in the Amazonian summer contained six major sesquiterpene compounds (ß-bisabolene, cis-eudesma-6,11-diene, trans-α-bergamotene, ß-selinene, α-selinene, and ß-elemene) and was nontoxic at a dose of 2000 mg/kg, showing low acute toxicity. Different from oleoresin obtained from other sites of the Brazilian Amazon, the major volatile compound found was ß-Bisabolene with 25.15%. This ß-Bisabolene-rich oleoresin reduced the formation of paw edema induced by carrageenan and reduced the global number of cells in the air pouch assay, as well as exudate volume and nitrite, TNF-α, IL-1ß, and prostaglandin E2 levels (p < 0.05). C. reticulata oleoresin with a high ß-Bisabolene concentration showed anti-inflammatory activity, reducing vascular permeability and consequently edema formation, and thus reducing cell migration and the production of inflammatory cytokine, confirming its traditional use by local Amazonian communities.

Use of naproxen versus intracervical block for pain control during the 52-mg levonorgestrel-releasing intrauterine system insertion in young women: a multivariate analysis of a randomized controlled trial.

BACKGROUND: To compare the effectiveness of 550 mg naproxen sodium versus 6 mL 2%-lidocaine intracervical block in pain lowering at the 52-mg levonorgestrel-releasing intrauterine system (LNG-IUS) placement in young women. METHODS: In this randomized controlled trial, 100 women aged 15-24 years were block-randomized to receive either 6 mL 2%-lidocaine intracervical block 5 min before the LNG-IUS insertion or 550 mg naproxen 30 min before the procedure. Forty-nine women received 550 mg naproxen and 51 received intracervical block. The primary outcome was pain at LNG-IUS insertion. Secondary outcomes were ease of insertion, insertion failures, and correct IUS positioning. Neither participants nor doctors were blinded. Pain at insertion was assessed by using a Visual Analog Scale (VAS). RESULTS: Women randomized to lidocaine intracervical block presented lower mean pain score at insertion, when compared to women who received naproxen (5.4 vs. 7.3, respectively; p < 0.001). Parous women had a 90.1% lower chance of experiencing severe pain (p = 0.004). There was a 49.8% reduction in the chance of severe pain for every 1-cm increase in the hysterometry (p = 0.002). The only complication observed during insertion was vasovagal-like reactions (7%). The insertion was performed without difficulty in 82% of the women. Participants in the intracervical block group presented higher proportion of malpositioned IUS on transvaginal ultrasound examination compared to women in naproxen group. Nevertheless, all the malpositioned IUS were inserted by resident physicians. CONCLUSION: Lidocaine intracervical block was found to be more effective than naproxen in reducing LNG-IUS insertion pain. TRIAL REGISTRATION NUMBER: RBR-68mmbp, Brazilian Registry of Clinical Trials, Retrospectively registered (August 4, 2020), URL of trial registry record: https://ensaiosclinicos.gov.br/rg/RBR-68mmbp/ .

Field and classroom initiatives for portable sequence-based monitoring of dengue virus in Brazil.

Brazil experienced a large dengue virus (DENV) epidemic in 2019, highlighting a continuous struggle with effective control and public health preparedness. Using Oxford Nanopore sequencing, we led field and classroom initiatives for the monitoring of DENV in Brazil, generating 227 novel genome sequences of DENV1-2 from 85 municipalities (2015-2019). This equated to an over 50% increase in the number of DENV genomes from Brazil available in public databases. Using both phylogenetic and epidemiological models we retrospectively reconstructed the recent transmission history of DENV1-2. Phylogenetic analysis revealed complex patterns of transmission, with both lineage co-circulation and replacement. We identified two lineages within the DENV2 BR-4 clade, for which we estimated the effective reproduction number and pattern of seasonality. Overall, the surveillance outputs and training initiative described here serve as a proof-of-concept for the utility of real-time portable sequencing for research and local capacity building in the genomic surveillance of emerging viruses.

Short report: Introduction of chikungunya virus ECSA genotype into the Brazilian Midwest and its dispersion through the Americas.

Since introduction into Brazil in 2014, chikungunya virus (CHIKV) has presented sustained transmission, although much is unknown about its circulation in the midwestern states. Here, we analyze 24 novel partial and near complete CHIKV genomes from Cuiaba, an urban metropolis located in the Brazilian midwestern state of Mato Grosso (MT). Nanopore technology was used for sequencing CHIKV complete genomes. Phylogenetic and epidemiological approaches were used to explore the recent spatio-temporal evolution and spread of the CHIKV-ECSA genotype in Midwest Brazil as well as in the Americas. Epidemiological data revealed a reduction in the number of reported cases over 2018-2020, likely as a consequence of a gradual accumulation of herd-immunity. Phylogeographic reconstructions revealed that at least two independent introductions of the ECSA lineage occurred in MT from a dispersion event originating in the northeastern region and suggest that the midwestern Brazilian region appears to have acted as a source of virus transmission towards Paraguay, a bordering South American country. Our results show a complex dynamic of transmission between epidemic seasons and suggest a possible role of Brazil as a source for international dispersion of the CHIKV-ECSA genotype to other countries in the Americas.

Coronavirus 2019 y personas en situación de calle en el estado de Mato Grosso, Brasil / Coronavirus 2019 and people living on the streets in Mato Grosso State, Brazil

Introducción: La expansión de Coronavirus Disease 2019 (COVID-19) en nuevos territorios representa un gran desafío para la salud pública en el mundo, especialmente para países como Brasil, debido a sus amplias extensiones territoriales y desigualdades regionales. Objetivos: Describir, durante la pandemia, el brote de COVID-19 en una población sin hogar en el interior de Mato Grosso, Brasil. Métodos: Estudio descriptivo sobre un brote de COVID-19 en el interior del estado de Mato Grosso. Los datos fueron recolectados de los registros documentales de la investigación epidemiológica municipal, en línea con el Sistema Único de Salud. Resultados: Del caso índice, una persona en situación de calle que fue trasladada al albergue municipal de Tangará da Serra/Mato Grosso, 47 personas infectadas por Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) fueron confirmadas por pruebas serológicas y/o moleculares: (i) en el albergue: 8 personas en situación de calle y 5 empleados; (ii) contacto con el hogar de los empleados: 3 miembros de la familia; (iii) en la unidad hospitalaria: 19 profesionales y 6 pacientes en la unidad de cuidados intensivos. Conclusiones: La falta de protección individual fue un factor decisivo para la infección por SARS-CoV-2 en el caso índice y se extendió en el albergue por la participación de contactos en el hogar. Además de los profesionales en el entorno hospitalario, donde el brote se produjo debido a factores estructurales, la falta de equipos de protección personal adecuados y la falta de una cuidadosa adopción de la bioseguridad(AU)

Introduction: The expansion of Coronavirus Disease 2019 (COVID-19) in new territories represents great challenge for public health in the world, especially for countries like Brazil, due to its wide territorial extensions and regional inequalities. Objectives: To describe, during the pandemic, the COVID-19 outbreak in homeless people in inner Mato Grosso, Brazil. Methods: A descriptive study on COVID-19 outbreak was carried out in inner Mato Grosso state. The data were collected from the documentary records of the municipal epidemiological investigation, in line with the Unified Health System. Results: From the index case, a person living on the street who was transferred to the municipal shelter in Tangará da Serra, Mato Grosso. Forty seven (47) people got infected by Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) and they were confirmed by serological tests and / or molecular: (i) in the shelter: 8 homeless people and 5 employees; (ii) contact with the employees' home: 3 family members; (iii) in the hospital unit: 19 professionals and 6 patients in the intensive care unit. Conclusions: The lack of individual protection was a critical factor for SARS-CoV-2 infection in the index case and it spreads in the shelter due to the involvement of domestic contacts. In addition to professionals in the hospital environment, where the outbreak occurred due to structural factors, the lack of adequate personal protection equipment and the lack of careful adoption of biosecurity(AU)

Chikungunya virus ECSA lineage reintroduction in the northeasternmost region of Brazil.

The Northeast region of Brazil registered the second-highest incidence proportion of Chikungunya fever in 2019. In that year, an outbreak consisting of patients presenting with febrile disease associated with joint pain was reported by the public primary health care service in the city of Natal, in the state of Rio Grande do Norte, in March 2019. At first, the aetiological agent of the disease was undetermined. Since much is still unknown about chikungunya virus' (CHIKV) genomic diversity and evolutionary history in this northeasternmost state, we used a combination of portable whole-genome sequencing, molecular clock, and epidemiological analyses that revealed the reintroduction of the CHIKV East-Central-South-African (ECSA) lineage into Rio Grande do Norte. We estimated that the CHIKV ECSA lineage was first introduced into Rio Grande do Norte in early June 2014, while the 2019 outbreak clade diverged around April 2018, during a period of increased Chikungunya incidence in the Southeast region, which might have acted as a source of virus dispersion towards the Northeast region. Together, these results confirm that the ECSA lineage continues to spread across the country through interregional importation events, likely mediated by human mobility.

Prevalence of hepatitis B and D virus infection in a district of Mato Grosso, bordering Amazonas and Rondônia states.

INTRODUCTION: Brazil's western Amazon basin has the highest prevalence of hepatitis B virus (HBV) infection in the country. Coinfection with hepatitis D virus (HDV) is also endemic. To estimate the prevalence of HBV and HDV markers in a population inhabiting the northwest portion of Mato Grosso state in the western Amazon. METHODS: We performed a cross-sectional study of the seroprevalence of antibodies against HBV core antigen (anti-HBc) in the Três Fronteiras District northwest of Mato Grosso. Anti-HBc-positive subjects were tested for HBV surface antigen (HBsAg). Those positive for this marker were tested for HDV antibodies. Anti-HBc-negative participants were tested for anti-HBsAg. All tests were performed by EIA. RESULTS: A total of 623 individuals in the community were assessed; the majority (67.6%) were male, with a mean age of 30.8 ± 15.4 years. Two hundred and fourteen individuals (34.3%) were anti-HBc-positive, and 47 (7.5%) were HBsAg carriers. Only one individual was anti-HDV-positive. Among the 409 individuals without HBV infection, 18.3% were anti-HBsAg-positive. There was no association between HBV infection and known risk factors. CONCLUSIONS: The study area had intermediate-to-high endemicity for HBV infection, but a low prevalence of HDV. Our serological results suggesting low vaccination-induced protection indicate a need for reinforced immunization programs in the populations of northwest Mato Grosso.

Prevalence of hepatitis B and D virus infection in a district of Mato Grosso, bordering Amazonas and Rondônia states

Abstract INTRODUCTION: Brazil's western Amazon basin has the highest prevalence of hepatitis B virus (HBV) infection in the country. Coinfection with hepatitis D virus (HDV) is also endemic. To estimate the prevalence of HBV and HDV markers in a population inhabiting the northwest portion of Mato Grosso state in the western Amazon. METHODS: We performed a cross-sectional study of the seroprevalence of antibodies against HBV core antigen (anti-HBc) in the Três Fronteiras District northwest of Mato Grosso. Anti-HBc-positive subjects were tested for HBV surface antigen (HBsAg). Those positive for this marker were tested for HDV antibodies. Anti-HBc-negative participants were tested for anti-HBsAg. All tests were performed by EIA. RESULTS: A total of 623 individuals in the community were assessed; the majority (67.6%) were male, with a mean age of 30.8 ± 15.4 years. Two hundred and fourteen individuals (34.3%) were anti-HBc-positive, and 47 (7.5%) were HBsAg carriers. Only one individual was anti-HDV-positive. Among the 409 individuals without HBV infection, 18.3% were anti-HBsAg-positive. There was no association between HBV infection and known risk factors. CONCLUSIONS: The study area had intermediate-to-high endemicity for HBV infection, but a low prevalence of HDV. Our serological results suggesting low vaccination-induced protection indicate a need for reinforced immunization programs in the populations of northwest Mato Grosso.

[Outbreak of foodborne disease at a mass event of indigenous peoples in Cuiaba, Mato Grosso, Brazil, in 2013]. / Surto de doença transmitida por alimento em evento de massa de populações indígenas em Cuiabá, Mato Grosso, Brasil, no ano de 2013.

OBJECTIVE: to report the experience of investigating the outbreak of acute diarrhoea (AD) at the XII Indigenous Games in Cuiabá, Mato Grosso, Brazil, 2013. METHODS: data were collected from the Advanced Medical Post's service records of the AD cases, which were defined as 'individual Games participant referring episode of diarrhoea and/or vomiting'; AD attack rates, relative frequencies and measures of the central tendency of sociodemographic and clinical variables, sanitary inspections and results of bromatological samples were calculated. RESULTS: 384 (37%) cases met the definition of AD; the epidemic peaks of the outbreak occurred on the 4th and 7th day of the event and the disease attack rate was 33.5%; sanitary inspection showed evidence of food contamination by coagulase-negative Staphylococci, Bacillus cereus and heat resistant coliforms. CONCLUSION: there an outbreak of AD caused by food contamination.

Geographic information systems and logistic regression for high-resolution malaria risk mapping in a rural settlement of the southern Brazilian Amazon.

BACKGROUND: In Brazil, 99% of the cases of malaria are concentrated in the Amazon region, with high level of transmission. The objectives of the study were to use geographic information systems (GIS) analysis and logistic regression as a tool to identify and analyse the relative likelihood and its socio-environmental determinants of malaria infection in the Vale do Amanhecer rural settlement, Brazil. METHODS: A GIS database of georeferenced malaria cases, recorded in 2005, and multiple explanatory data layers was built, based on a multispectral Landsat 5 TM image, digital map of the settlement blocks and a SRTM digital elevation model. Satellite imagery was used to map the spatial patterns of land use and cover (LUC) and to derive spectral indices of vegetation density (NDVI) and soil/vegetation humidity (VSHI). An Euclidian distance operator was applied to measure proximity of domiciles to potential mosquito breeding habitats and gold mining areas. The malaria risk model was generated by multiple logistic regression, in which environmental factors were considered as independent variables and the number of cases, binarized by a threshold value was the dependent variable. RESULTS: Out of a total of 336 cases of malaria, 133 positive slides were from inhabitants at Road 08, which corresponds to 37.60% of the notifications. The southern region of the settlement presented 276 cases and a greater number of domiciles in which more than ten cases/home were notified. From these, 102 (30.36%) cases were caused by Plasmodium falciparum and 174 (51.79%) cases by Plasmodium vivax. Malaria risk is the highest in the south of the settlement, associated with proximity to gold mining sites, intense land use, high levels of soil/vegetation humidity and low vegetation density. CONCLUSIONS: Mid-resolution, remote sensing data and GIS-derived distance measures can be successfully combined with digital maps of the housing location of (non-) infected inhabitants to predict relative likelihood of disease infection through the analysis by logistic regression. Obtained findings on the relation between malaria cases and environmental factors should be applied in the future for land use planning in rural settlements in the Southern Amazon to minimize risks of disease transmission.

Spatial patterns of malaria in a land reform colonization project, Juruena municipality, Mato Grosso, Brazil.

BACKGROUND: In Brazil, 99% of malaria cases are concentrated in the Amazon, and malaria's spatial distribution is commonly associated with socio-environmental conditions on a fine landscape scale. In this study, the spatial patterns of malaria and its determinants in a rural settlement of the Brazilian agricultural reform programme called "Vale do Amanhecer" in the northern Mato Grosso state were analysed. METHODS: In a fine-scaled, exploratory ecological study, geocoded notification forms corresponding to malaria cases from 2005 were compared with spectral indices, such as the Normalized Difference Vegetation Index (NDVI) and the third component of the Tasseled Cap Transformation (TC_3) and thematic layers, derived from the visual interpretation of multispectral TM-Landsat 5 imagery and the application of GIS distance operators. RESULTS: Of a total of 336 malaria cases, 102 (30.36%) were caused by Plasmodium falciparum and 174 (51.79%) by Plasmodium vivax. Of all the cases, 37.6% (133 cases) were from residents of a unique road. In total, 276 cases were reported for the southern part of the settlement, where the population density is higher, with notification rates higher than 10 cases per household. The local landscape mostly consists of open areas (38.79 km²). Training forest occupied 27.34 km² and midsize vegetation 7.01 km². Most domiciles with more than five notified malaria cases were located near areas with high NDVI values. Most domiciles (41.78%) and malaria cases (44.94%) were concentrated in areas with intermediate values of the TC_3, a spectral index representing surface and vegetation humidity. CONCLUSIONS: Environmental factors and their alteration are associated with the occurrence and spatial distribution of malaria cases in rural settlements.