Mapping the Silent Threat: A Comprehensive Analysis of Chagas Disease Occurrence in Riverside Communities in the Western Amazon.

Chagas disease (CD) is a typical tropical illness caused by Trypanosoma cruzi. The objective of this study was to assess the prevalence of Chagas disease in communities in two states of the Brazilian Amazon. Data collection occurred in July in the Alto Juruá region of Acre and in December in the communities of Humaitá, Amazonas, in 2019. A total of 477 participants were included in the study. In the communities of Alto Juruá, triatomine collections and analyses of T. cruzi infection were also carried out. All confirmed cases were found in the state of Acre, resulting in a total prevalence of 1.67. Of these eight cases, seven underwent ECG, all of which were concluded as normal by the physician team's cardiologists. Seventeen triatomine bugs, all belonging to the Rhodnius genus, were captured. The natural infection rate by T. cruzi was 25% in the Nova Cintra community and 66.67% in the Boca do Moa community (Alto Juruá). This research found that more than 1% of the studied population exhibited positive serological results for Chagas disease in the riverine communities during the study period, representing a small portion of cases among those who have not yet been diagnosed.

Acute Chagas Disease Caused by Trypanosoma cruzi TcIV and Transmitted by Panstrongylus geniculatus: Molecular Epidemiological Insights Provided by the First Documented Autochthonous Case in Rondônia, Southwestern Amazonia, Brazil.

Recurrent outbreaks of oral infection and isolated cases characterize the new epidemiological scenario of Chagas disease (CD) in the Brazilian Amazon. Acute Chagas disease (ACD) is common in Pará and Amazonas, Northeastern and Northwestern Brazilian Amazonia. In the present study, we describe the first molecularly characterized autochthonous case of ACD in Rondônia, Southwestern Amazonia. The patient, a 39-year-old male resident in the small city of Cujubim, presented typical ACD symptoms: fever, asthenia, myalgia, progressive dyspnea, swelling of the legs, and tiredness at minimal efforts, all compatible with ACD and indicative of cardiac involvement. A thick blood drop test revealed trypomastigote forms of Trypanosoma cruzi genotyped as TcIV. An epidemiological investigation ruled out oral infection, and support for vectorial transmission included the finding of Panstrongylus geniculatus positive for T. cruzi (TcIII and TcIV) inside the tent used by the patient when harvesting forest timber, and a circular cutaneous lesion resembling a chagoma of inoculation. Treatment with benznidazole led to blood parasite clearance as confirmed by molecular tests. Altogether, our findings fitted well into the ecological scenario where deforestation and colonization of forested areas represent an important risk factor to the adaptation of P. geniculatus to human habitats, favoring vectorial transmission of CD in the Amazonian region.

Chromoblastomycosis in the Amazon region, Brazil, caused by Fonsecaea pedrosoi, Fonsecaea nubica, and Rhinocladiella similis: Clinicopathology, susceptibility, and molecular identification.

Chromoblastomycosis is a chronic subcutaneous disease caused by human contact with melanized fungi occurring mainly in tropical and subtropical zones worldwide. This study assessed 12 patients with chromoblastomycosis from Rondônia, Brazil, Amazon region. In sum, 83.3% were men, 41.6% were from Monte Negro city, median age was 52.9 years, and median time to disease progression was 12.2 years. Lesions were located on the lower limbs (75%), and verruciform was prevalent form (66.6%). After 3 years of treatment with itraconazole, two patients were considered cured. The etiological agents were identified by the molecular sequence of the ribosomal internal transcribed spacer ITS1, 5.8S, and ITS2 region and ß-tubulin genes. Eight strains were identified as Fonsecaea pedrosoi, two were F. nubica, and two were Rhinocladiella similis. The antifungal activity of five drugs was evaluated, and the most active drug was terbinafine (range minimal inhibitory concentration [MIC] 0.015-0.12 µg/ml), itraconazole (range MIC 0.03-0.5 µg/ml) and voriconazole (range MIC 0.06-0.5 µg/ml). The highest MIC was 5-fluorocytosine (range MIC 2-32 µg/ml), and amphotericin B (range MIC 0.25-2 µg/ml). In conclusion, the present study expanded the epidemiological disease database and described for the first time F. nubica and R. similis as chromoblastomycosis agents in the Brazilian Amazon region. Our results confirmed the importance of using molecular methods to identify the melanized fungi and stimulate the recognition of the disease in other places where no cases have been reported.

Chromoblastomycosis in the amazon region, BRazil, caused by fonsecaea pedrosoi, fonsecaea nubica, and Rhinocladiella similis: clinicopathology, susceptibility, and molecular identification

Chromoblastomycosis is a chronic subcutaneous disease caused by human contact with melanized fungioccurring mainly in tropical and subtropical zones worldwide. This study assessed 12 patients with chro-moblastomycosis from Rondˆonia, Brazil, Amazon region. In sum, 83.3% were men, 41.6% were from MonteNegro city, median age was 52.9 years, and median time to disease progression was 12.2 years. Lesions werelocated on the lower limbs (75%), and verruciform was prevalent form (66.6%). After 3 years of treatmentwith itraconazole, two patients were considered cured. The etiological agents were identified by the molec-ular sequence of the ribosomal internal transcribed spacer ITS1, 5.8S, and ITS2 region andß-tubulin genes.Eight strains were identified asFonsecaea pedrosoi, two wereF. nubica,and two wereRhinocladiella similis.The antifungal activity of five drugs was evaluated, and the most active drug was terbinafine (range minimalinhibitory concentration [MIC] 0.015­0.12µg/ml), itraconazole (range MIC 0.03­0.5µg/ml) and voriconazole(range MIC 0.06­0.5µg/ml). The highest MIC was 5-fluorocytosine (range MIC 2­32µg/ml), and ampho-tericin B (range MIC 0.25­2µg/ml). In conclusion, the present study expanded the epidemiological diseasedatabase and described for the first timeF. nubicaandR. similisas chromoblastomycosis agents in theBrazilian Amazon region. Our results confirmed the importance of using molecular methods to identify themelanized fungi and stimulate the recognition of the disease in other places where no cases have beenreported.

Transition of the morbidity and mortality profile in a municipality in the interior of the Brazilian Amazon.

INTRODUCTION: The morbidity and mortality profile in a given region reflects its quality of life and provides tools for improving public health policies in that region. METHODS: A cross-sectional epidemiological study was performed using secondary mortality data collected from the Monte Negro municipality of the Brazilian Western Amazon from 2000 to 2011. These data were compared with data from similar municipalities in other Brazilian macro-regions. Data were obtained through the Departamento de Informática do Sistema Único de Saúde (DATASUS) information system. RESULTS: The number of deaths reported over the study period was 606. The most common cause of death was external causes of morbidity and mortality [International Classification of Diseases (ICD)-10 chapter 20], followed by diseases of the circulatory system (ICD-10 chapter 9). Among the causes of death according to age group, infectious and parasitic diseases were the most common for 2- to 9-year-old children; external causes of disease were the most prevalent for 10- to 59-year-old people; and circulatory diseases prevailed in individuals over 60 years of age. Eleven percent of deaths were due to unknown causes. CONCLUSIONS: These results point to a fragility in the public policies for prevention and awareness of this problem. Infectious and parasitic diseases contribute only 4.5% of deaths, but had the third highest Disability-Adjusted Life Year score (1,190 days). Improving support to the Estratégia Saúde da Família (Family Health Strategy) program and implementing a death verification service would significantly aid in reducing the occurrence of non-transmissible chronic diseases and clarifying unknown causes of death.

Transition of the morbidity and mortality profile in a municipality in the interior of the Brazilian Amazon

Abstract: INTRODUCTION: The morbidity and mortality profile in a given region reflects its quality of life and provides tools for improving public health policies in that region. METHODS A cross-sectional epidemiological study was performed using secondary mortality data collected from the Monte Negro municipality of the Brazilian Western Amazon from 2000 to 2011. These data were compared with data from similar municipalities in other Brazilian macro-regions. Data were obtained through the Departamento de Informática do Sistema Único de Saúde (DATASUS) information system. RESULTS The number of deaths reported over the study period was 606. The most common cause of death was external causes of morbidity and mortality [International Classification of Diseases (ICD)-10 chapter 20], followed by diseases of the circulatory system (ICD-10 chapter 9). Among the causes of death according to age group, infectious and parasitic diseases were the most common for 2- to 9-year-old children; external causes of disease were the most prevalent for 10- to 59-year-old people; and circulatory diseases prevailed in individuals over 60 years of age. Eleven percent of deaths were due to unknown causes. CONCLUSIONS These results point to a fragility in the public policies for prevention and awareness of this problem. Infectious and parasitic diseases contribute only 4.5% of deaths, but had the third highest Disability-Adjusted Life Year score (1,190 days). Improving support to the Estratégia Saúde da Família (Family Health Strategy) program and implementing a death verification service would significantly aid in reducing the occurrence of non-transmissible chronic diseases and clarifying unknown causes of death.

Occurrence of Mansonella ozzardi diagnosed using a polycarbonate membrane in a riverside population of Lábrea in the Western Brazilian Amazon.

INTRODUCTION Mansonella ozzardi is a widely distributed filaria worm in the Amazon region. This study aimed to determine the prevalence of M. ozzardi infection in riverine communities of Lábrea municipality, Amazonas State, Brazil. METHODS A diagnostic blood filtration method in a polycarbonate membrane was used. RESULTS M. ozzardi was found in 50.3% of the sample, with the highest prevalence in farmers/fishermen (69.4%; χ 2 = -19.14, p<0.001). The prevalence was higher in longer-term residents (≥11 years; 60.2%). CONCLUSIONS M. ozzardi infection rates are high near the Purus River, much greater than those previously reported based on diagnosis using thick blood smears.

Toxoplasma gondii, Neospora caninum and Leishmania amazonensis antibodies in domestic dogs in the western Brazilian Amazon region / Toxoplasma gondii, Neospora caninum e Leishmania amazonensis em cães domésticos da Amazônia Ocidental Brasileira

Amostras de sangue de 99 cães domiciliados foram coletadas no meio urbano (n = 33) e rural (n = 66) do município de Lábrea, estado do Amazonas, Brasil. Dentre as amostras rurais, 40 foram obtidas em comunidades ribeirinhas e 26 em comunidades indígenas, ambas ao longo do rio Purus. Durante a amostragem foi aplicado um questionário com informações sobre sexo, idade, viver em áreas secas ou alagadiças, acesso ou não às ruas (cães urbanos) e acesso à floresta. A presença de anticorpos contra Toxoplasma gondii, Neospora caninum, Leishmania infantum chagasi e Leishmania amazonensis foi detectada pela reação de imunofluorescência indireta (RIFI) com ponto de corte de, respectivamente, 16, 50, 40 e 40. Associação entre as variáveis qualitativas e a positividade para cada um dos parasitos foi avaliada pelo teste do χ2 (p < 0,05). A ocorrência de animais com anticorpos contra T. gondii, N. caninum e L. amazonensis foi de, respectivamente, 61,6%; 7,1% e 8,1%. Nenhuma amostra foi positiva para L. infantum chagasi. A variável viver em área urbana (p=0,041) apresentou associação com ocorrência de T. gondii e o número de cães positivos a T. gondii aumentou com a idade (p = 0,0006). A variável sexo (machos) apresentou associação com N. caninum (p = 0,018) e nenhuma variável apresentou associação com L. amazonensis. Os títulos de anticorpos contra T. gondii variaram de 64 a 32.768; contra N. caninum de 100 a 800 e contra L. amazonensis de 40 a 640. T. gondii e L. amazonensis são dois agentes de importantes zoonoses e encontram-se ativos na região. O município estudado, especialmente as comunidades ribeirinhas, possuem peculiaridades geográficas, sociais e ecológicas distintas e necessitam maior atenção das autoridades para o controle desses agentes.(AU)

Blood samples from 99 domestic dogs were collected in the urban area (n = 33) and rural area (n = 66) of the municipality of Lábrea, state of Amazonas, Brazil. Among the rural samples, 40 were collected in riverine communities and 26 were collected in Indian communities, both along the Purus River. During the sampling, a questionnaire was applied to obtain information relating to sex, age, living in dryland or seasonally flooded areas, access to the streets (for urban dogs) and access to forests. The presence of antibodies against Toxoplasma gondii, Neospora caninum, Leishmania infantum chagasi and Leishmania amazonensis was detected by means of the indirect fluorescent antibody test (IFAT) with cutoffs of 16, 50, 40 and 40, respectively. The association of each qualitative variable, with each parasite and positivity for each of them, were evaluated using the χ2 test (p < 0.05). T. gondii, N. caninum and L. amazonensis antibodies were found, respectively, in 61.6%, 7.1% and 8.1% of the animals examined. None of the samples were positive for L. infantum chagasi. The variable of living in an urban area (p = 0.041) presented an association with occurrence of T. gondii and the positivity for T. gondii increased with age of the dogs (p = 0.0006). The variable of male sex presented an association with N. caninum (p = 0.018) and no variable presented any association with L. amazonensis. The antibody titers against T. gondii ranged from 64 to 32,768; against N. caninum from 100 to 800; and against L. amazonensis from 40 to 640. Both T. gondii and L. amazonensis are important zoonotic agents and are active in this region. The municipality studied, and especially its riverine communities, has geographic, social and ecological peculiarities. This region requires greater attention from the authorities for controlling these agents.(AU)

Characteristics relating to the interiorization of acquired immunodeficiency syndrome in Brazil: a cross-sectional study.

BACKGROUND: In recent years there has been changes in the social and geographic profile of acquired immunodeficiency syndrome (AIDS). The aim of this study was to evaluate the internalization of AIDS in the state of Rondônia, Brazil. FINDINGS: In Rondônia, 1473 AIDS cases were reported, with an average annual incidence of 15.8/100,000 persons (42.7 % women). The most common mode of viral transmission was sexual (96.5 %), and the majority of the individuals had not completed their primary education (64.8 %). There was heterogeneity in relation to case distribution, involving almost all of the municipalities in the state. The average annual mortality rate was 2.5/100,000 persons. CONCLUSION: Rondônia has a higher incidence of AIDS than the national average and the northern region. Efforts to provide access to treatment and follow-up of these individuals should be implemented, prioritizing areas where the incidence is higher and decentralizing the treatment of patients with AIDS in the state.

Epidemiological aspects of Toxoplasma gondii infection in riverside communities in the Southern Brazilian Amazon.

INTRODUCTION: Toxoplasma gondii infection is widely prevalent in humans and other animals worldwide. Information on the prevalence of T. gondii infection is scarce in some regions of Brazil, including riverside communities along the Amazon River basin. M METHODS: The prevalence of T. gondii in 231 people, aged 1-85 years, who were living in four riverside communities along the Purus River, Lábrea, State of Amazonas, Brazil, was determined. Antibodies against T. gondii were assayed using a commercial enzyme-linked immunosorbent assay (ELISA) kit. The hearts and brains of 50 chickens, which were raised free-range in the communities, were pooled according to the community of origin and bioassayed in mice. The isolates were genotyped using polymorphisms at 12 nuclear markers (SAG1, 5' and 3'-SAG2, alt.SAG2, SAG3, BTUB, GRA6, c22-8, c29-2, L358, PK1, Apico and CS3). RESULTS: The overall seroprevalence of T. gondii was 56.7% (131/231). IgG antibodies were presented by 117 (89.3%) and IgM by 14 (10.7%) of the 131 positive individuals. No association between age group and gender with prevalence was observed (chi-square test, p > 0.05); however, the comparison between localities showed that the seroprevalence of T. gondii was significantly lower among the individuals living in the Boca do Ituxi (p < 0.05) community. Five isolates of T. gondii were obtained in the mouse bioassay, and genotyping revealed two complete genotypes that had not been described previously and three mixed isolates. CONCLUSIONS: These results support previous findings that T. gondii population genetics are highly diverse in Brazil and that T. gondii infection is active in these riverside communities.

Epidemiological aspects of Toxoplasma gondii infection in riverside communities in the Southern Brazilian Amazon

INTRODUCTION: Toxoplasma gondii infection is widely prevalent in humans and other animals worldwide. Information on the prevalence of T. gondii infection is scarce in some regions of Brazil, including riverside communities along the Amazon River basin. M METHODS: The prevalence of T. gondii in 231 people, aged 1-85 years, who were living in four riverside communities along the Purus River, Lábrea, State of Amazonas, Brazil, was determined. Antibodies against T. gondii were assayed using a commercial enzyme-linked immunosorbent assay (ELISA) kit. The hearts and brains of 50 chickens, which were raised free-range in the communities, were pooled according to the community of origin and bioassayed in mice. The isolates were genotyped using polymorphisms at 12 nuclear markers (SAG1, 5' and 3'-SAG2, alt.SAG2, SAG3, BTUB, GRA6, c22-8, c29-2, L358, PK1, Apico and CS3). RESULTS: The overall seroprevalence of T. gondii was 56.7% (131/231). IgG antibodies were presented by 117 (89.3%) and IgM by 14 (10.7%) of the 131 positive individuals. No association between age group and gender with prevalence was observed (chi-square test, p > 0.05); however, the comparison between localities showed that the seroprevalence of T. gondii was significantly lower among the individuals living in the Boca do Ituxi (p < 0.05) community. Five isolates of T. gondii were obtained in the mouse bioassay, and genotyping revealed two complete genotypes that had not been described previously and three mixed isolates. CONCLUSIONS: These results support previous findings that T. gondii population genetics are highly diverse in Brazil and that T. gondii infection is active in these riverside communities. .

Study of the prevalence of Capillaria hepatica in humans and rodents in an urban area of the city of Porto Velho, Rondônia, Brazil.

INTRODUCTION: Hepatic capillariosis, caused by Capillaria hepatica (Calodium hepaticum) (Bancroft, 1893), Travassos, 1915 (Nematoda, Trichinelloidea, Capillariidae), is a common zoonosis in rodents but is rare in humans. Seventy-two cases in humans have been reported worldwide since the first case was described by MACARTHUR in 192417,27. This study aimed to determine the prevalence of Capillaria hepatica in humans and rodents in an urban area of Porto Velho, the capital of Rondônia, in Brazil. METHODS: After conducting a census of the area, 490 residents were randomly selected, and, after signing a term of consent, provided blood samples that were screened for anti-Capillaria hepatica antibodies. Simultaneously, rats were captured to assess the prevalence of this parasite in rodents by histopathological examination in liver sections. RESULTS: A prevalence of 1.8% was found among residents who had specific antibodies at a dilution of 1:150, indicating exposure to parasite eggs; 0.8% of the subjects also had positive titers at a dilution of 1:400, indicating true infection. The prevalence in rats was 2%. CONCLUSIONS: The prevalence of infection with this parasite among humans and rats was low. While the prevalence encountered among humans was within the limits reported in the literature, the prevalence among rodents was much lower.

Study of the prevalence of capillaria hepatica in humans and rodents in an urban area of the city of Porto Velho, Rondônia, Brazil / Estudo da prevalência da Capillaria hepatica em humanos e roedores em área urbana da cidade de Porto Velho, Rondônia, Brasil

Introduction: Hepatic capillariosis, caused by Capillaria hepatica (Calodium hepaticum) (Bancroft, 1893), Travassos, 1915 (Nematoda, Trichinelloidea, Capillariidae), is a common zoonosis in rodents but is rare in humans. Seventy-two cases in humans have been reported worldwide since the first case was described by MACARTHUR in 192417,27. This study aimed to determine the prevalence of Capillaria hepatica in humans and rodents in an urban area of Porto Velho, the capital of Rondônia, in Brazil. Methods: After conducting a census of the area, 490 residents were randomly selected, and, after signing a term of consent, provided blood samples that were screened for anti-Capillaria hepatica antibodies. Simultaneously, rats were captured to assess the prevalence of this parasite in rodents by histopathological examination in liver sections. Results: A prevalence of 1.8% was found among residents who had specific antibodies at a dilution of 1:150, indicating exposure to parasite eggs; 0.8% of the subjects also had positive titers at a dilution of 1:400, indicating true infection. The prevalence in rats was 2%. Conclusions: The prevalence of infection with this parasite among humans and rats was low. While the prevalence encountered among humans was within the limits reported in the literature, the prevalence among rodents was much lower.

Introdução: Capilaríase hepática é causada pela Capillaria hepatica (syn. Calodium hepaticum) (Bancroft, 1893), Travassos, 1915 (Nematoda, Trichinelloidea, Capillariidae), sendo uma zoonose comum entre roedores, porém rara em humanos. Setenta e dois casos humanos foram relatados na literatura mundial desde o primeiro caso descrito por MACARTHUR em 192417,27. O objetivo desse estudo é determinar a prevalência da Capillaria hepatica em humanos e roedores de área urbana da cidade de Porto Velho, capital de Rondônia, Brasil. Método: Após realizar um censo da área, 490 moradores foram aleatoriamente selecionados e assinaram termo de consentimento, foram colhidas amostras de sangue para testar anticorpos anti-Capillaria hepatica. Simultaneamente, ratos foram capturados para determinação da prevalência deste parasita através do exame histopatológico em cortes de fígado. Resultados: Foi encontrada entre humanos prevalência de 1,8% de positividade para anticorpos específicos em diluição de 1:150, indicando exposição aos ovos do parasito; 0,8% desses também deram testes positivos quando seus soros sofreram diluição de 1:400, indicando infecção verdadeira. Nos ratos, a prevalência foi de 2%. Conclusão: A prevalência encontrada para o parasito entre homens e roedores foi baixa. Enquanto a prevalência encontrada entre humanos esteve dentro dos limites encontrados na literatura, a prevalência entre roedores foi bem menor.

Insecticide-tretted bed nets in rondônia, Brazi: evaluation of their impact onn malaria control / Mosquiteiros impregnados com inseticida em Rondônia, Brasil: avaliação do impacto na incidência da malária

Mosquito nets treated with long-lasting insecticide (LLINs), when used in compliance with guidelines of the World Health Organization, may be effective for malaria vector control. In 2012, approximately 150,000 LLINs were installed in nine municipalities in the state of Rondônia. However, no studies have assessed their impact on the reduction of malaria incidence. This study analyzed secondary data of malaria incidence, in order to assess the impact of LLINs on the annual parasite incidence (API). The results showed no statistically significant differences in API one year after LLIN installation when compared to municipalities without LLINs. The adoption of measures for malaria vector control should be associated with epidemiological studies and evaluations of their use and efficiency, with the aim of offering convincing advantages that justify their implementation and limit malaria infection in the Amazon Region.

O uso de mosquiteiros impregnados com inseticida de longa duração (MILD), quando obedecidas as orientações da Organização Mundial da Saúde, é medida de controle de vetores da malária que pode apresentar excelentes resultados. Em 2012 foram instalados aproximadamente 150.000 MILDs em nove municípios do estado de Rondônia. Concomitantemente não houve estudo de avaliação de impacto na redução da incidência. O presente estudo analisou dados secundários da incidência, na expectativa de avaliar o impacto dos MILDs na incidência parasitária anual (IPA). Os resultados estatísticos mostram que, no período de um ano após a instalação dos MILDs, não houve diferença estatisticamente significativa na variação da IPA em relação a outros municípios que não receberam os MILDs. A adoção de medidas de controle vetorial deve ser acompanhada de estudos epidemiológicos e de avaliação de uso e eficácia para oferecer subsídios mais robustos que justifiquem a adoção desta medida de controle da malária na Região Amazônica.

Insecticide-treated bed nets in Rondônia, Brazil: evaluation of their impact on malaria control.

Mosquito nets treated with long-lasting insecticide (LLINs), when used in compliance with guidelines of the World Health Organization, may be effective for malaria vector control. In 2012, approximately 150,000 LLINs were installed in nine municipalities in the state of Rondônia. However, no studies have assessed their impact on the reduction of malaria incidence. This study analyzed secondary data of malaria incidence, in order to assess the impact of LLINs on the annual parasite incidence (API). The results showed no statistically significant differences in API one year after LLIN installation when compared to municipalities without LLINs. The adoption of measures for malaria vector control should be associated with epidemiological studies and evaluations of their use and efficiency, with the aim of offering convincing advantages that justify their implementation and limit malaria infection in the Amazon Region.

Reduction of incidence and relapse or recrudescence cases of malaria in the western region of the Brazilian Amazon.

INTRODUCTION: Malaria is one of the major parasitic diseases in the State of Rondônia, located in the western Brazilian Amazon. The basic treatment scheme for this disease is chloroquine and primaquine. This study evaluated the epidemiological profile of malaria in Rondônia between 2008 and 2012. METHODOLOGY: The epidemiological data were provided by the Health Surveillance Agency from the State of Rondônia, and socioeconomic indicators were obtained from the Brazilian Institute of Geography and Statistics, Department of Informatics of the Unified Health System, and from the National Institute for Space Research. The analyzed variables included year of diagnosis, gender, age group, main activity performed in the 15 days previous to the diagnosis, parasite species, level of parasitemia, number of relapse/recrudescence cases, and socioeconomic and environmental data for Rondônia. RESULTS: A total of 238,626 cases of malaria were recorded in Rondônia during the study period. Of this total, 65.6% were men and the most prevalent age group was 20-39 years. Plasmodium vivax was the most common parasite (89.8%), followed by Plasmodium   falciparum (9.4%). An average of 30.9% of the individuals who were tested presented with relapse/recrudescence malaria. The API value was highest in 2008 and lowest in 2012, corresponding to 42.3 cases and 19.2 cases per 1,000 inhabitants, respectively. CONCLUSIONS: A 58% reduction in the number of malaria cases and a 36.2% reduction in the number of relapse/recrudescence malaria cases were observed, due to increases in the economy, improvements in the health system, and reduction of deforestation in this region.

Sustained clearance of Mansonella ozzardi infection after treatment with ivermectin in the Brazilian Amazon.

Therapy for mansonelliasis is challenging because there is no standard drug recommended for its treatment. This non-randomized study was conducted to evaluate the effectiveness of a single dose of 0.15 mg/kg of ivermectin to reduce Mansonella ozzardi microfilaraemia in infected persons. A total of 74 patients were studied within the municipality of Lábrea, which is located in Amazonas State, Brazil. The patients were treated with ivermectin after detection of the parasite by blood examination. Significant microfilaraemia reduction was observed and its residual effect was maintained for at least 12 months. There was no significant change in the laboratory blood count, hepatic metabolites, and nitrogen-bounding compound excreta dosage values that could compromise the use of this drug, demonstrating that ivermectin has a low toxicity level.

Investigation of the occurrence of Mansonella ozzardi in the State of Rondônia, Western Amazonia, Brazil / Investigação da ocorrência da Mansonella ozzardi no Estado de Rondônia, Amazônia Ocidental

INTRODUCTION: Mansonella ozzardi, a human filarial nematode transmitted by Diptera Simuliidae flies (black flies), is widely spread in the Amazon, while the occurrence of mansonelliasis in the State of Rondônia (Western Amazonia) has not been reported thus far. The existence of this parasitic disease in this state is investigated in this study. METHODS: A total of 4,452 people who lived alongside the Madeira, Mamore, Guapore, Machado and Preto Rivers, in the State of Rondônia, were examined using the thick blood smear method. Alongside the Machado and Guapore rivers, 2,112 adult simuliid specimens were captured. RESULTS: Infected people were not reported, although simuliids with vector potential such as Cerqueirellum pydanielli, C. argentiscutum and C. amazonicum were found. CONCLUSIONS: This study registered no infected people. This finding may be explained by the individuals' low level of microfilaremia that is below the limit of detection of the diagnostic method used in the study or insufficient migration of people infected with M. ozzardi from endemic areas, making it impossible to introduce the disease into Rondônia. Further studies using more sensitive diagnostic techniques could shed light on this question.

INTRODUÇÃO: Mansonella ozzardi é uma filária humana que tem como vetor dípteros simulídeos e é amplamente distribuída na Amazônia. Não há informações sobre a ocorrência de casos de mansonelose no Estado de Rondônia, e neste trabalho procurou-se investigar a situação epidemiológica desta parasitose em áreas urbanas e ribeirinhas na Amazônia Ocidental. MÉTODOS: Foram examinados 4.452 moradores às margens dos rios Madeira, Mamoré, Guaporé, Machado e Preto em Rondônia, através da técnica da gota espessa de sangue. Capturou-se às margens do rio Machado e Guaporé 2.112 simulídeos adultos das espécies Cerqueirellum pydanieli e Chirostilbia pertinax. RESULTADOS: Não foram encontradas pessoas infectadas com M. ozzardi e foram encontradas diferentes espécies de simulídeos com potencial de transmissão da mansonelose. CONCLUSÕES: Não foram encontrados indivíduos infectados com M. ozzardi neste estudo. Este fato pode ser explicado pela existência de pacientes com baixas microfilaremias, associado à técnica diagnóstica de baixa sensibilidade utilizada no estudo. Pode-se ainda aventar a possibilidade de ter ocorrido migração insuficiente de pacientes infectados de áreas endêmicas, impossibilitando a implantação da endemia. Estudos posteriores com técnicas diagnósticas mais sensíveis podem ajudar a esclarecer esta questão.

Investigation of the occurrence of Mansonella ozzardi in the State of Rondônia, Western Amazonia, Brazil.

INTRODUCTION: Mansonella ozzardi, a human filarial nematode transmitted by Diptera Simuliidae flies (black flies), is widely spread in the Amazon, while the occurrence of mansonelliasis in the State of Rondônia (Western Amazonia) has not been reported thus far. The existence of this parasitic disease in this state is investigated in this study. METHODS: A total of 4,452 people who lived alongside the Madeira, Mamore, Guapore, Machado and Preto Rivers, in the State of Rondônia, were examined using the thick blood smear method. Alongside the Machado and Guapore rivers, 2,112 adult simuliid specimens were captured. RESULTS: Infected people were not reported, although simuliids with vector potential such as Cerqueirellum pydanielli, C. argentiscutum and C. amazonicum were found. CONCLUSIONS: This study registered no infected people. This finding may be explained by the individuals' low level of microfilaremia that is below the limit of detection of the diagnostic method used in the study or insufficient migration of people infected with M. ozzardi from endemic areas, making it impossible to introduce the disease into Rondônia. Further studies using more sensitive diagnostic techniques could shed light on this question.