BackgroundHuman capillariasis caused by Capillaria hepatica (syn. Calodium hepaticum) is a rare disease with no more than 40 cases registered around the world. Classically, the disease has severe symptoms that mimic acute hepatitis. Natural reservoirs of C. hepatica are urban rodents (Mus musculus and Rattus novergicus) that harbor their eggs in the liver. After examining the feces of 6 riverine inhabitants (Rio Preto area, 8° 03'S and 62° 53' W to 8° 14'S and 62° 52'W) of the State of Rondonia, Brazil, and identifying C. hepatica eggs in their feces, the authors decided to investigate the real dimension of these findings by looking for two positive signals.MethodsBetween June 1st and 15th, 2008, 246 out of 304 individuals were clinically examined. Blood samples were collected, kept under -20°C, and test by the indirect immunofluorescence technique.ResultsThe first positive signal was the presence of specific antibodies at 1:150 dilution, which indicates that the person is likely to have been exposed to eggs, most likely non-infective eggs, passing through the food chain or via contaminated food (total prevalence of 34.1%). A second more specific signal was the presence of antibodies at higher titers, thus indicating true infection.ConclusionsThe authors concluded that only two subjects were really infected (prevalence of 0.81%); the rest was false-positives that were sensitized after consuming non-embryonated eggs. The present study is the first one carried out in a native Amazonian population and indicates the presence of antibodies against C. hepatica in this population. The results further suggest that the transmission of the parasite occurs by the ingestion of embryonated eggs from human feces and/or carcasses of wild animals. The authors propose a novel mode of transmission, describing the disease as a low pathogenic one, and showing low infectivity.

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 β-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.

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. 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 freerange 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 signifi cantly 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 fi ndings that T. gondii population genetics are highly diverse in Brazil and that T. gondii infection is active in these riverside communities.

INTRODUCTION: Mansonelliasis is caused by Mansonella ozzardi. It is widespread in the Amazon region, with a high prevalence. The common exam of thick blood smears stained with Giemsa shows low efficacy levels and has been an obstacle to diagnosing individuals with low blood parasitemia. METHODS: In order to increase diagnosis efficacy, the PCR technique was improved. RESULTS AND CONCLUSIONS: PCR demonstrated the best performance, with sensitivity and negative predictive values (NPV) of 100%, followed by blood filtration through membrane filters, which showed a sensitivity of 88.9% and a NPV of 84.6%, when compared to thick blood smears.

Revista da Sociedade Brasileira de Medicina Tropical 46(2):214-220, Mar-Apr, 2013http://dx.doi. org/10.1590/0037-8682-1708-2013 Major Article INTRODUCTION Survey of Bancroftian filariasis infection in humans and ABSTRACT Introduction:The aim of this work was to identify possible lymphatic filariasis foci in the western Brazilian Amazonian that could be established from the reports of Rachou in the 1950s. The study was conducted in three cities of the western Brazilian Amazon region -Porto Velho and Guajará-Mirim (State of Rondônia) and Humaitá (State of Amazonas). Methods: For human infection evaluation thick blood smear stained with Giemsa was used to analyze samples collected from 10pm to 1am. Polymerase chain reaction (PCR) was used to examine mosquito vectors for the presence of Wuchereria bancrofti DNA. Humans were randomly sampled from night schools students and from inhabitants in neighborhoods lacking sanitation. Mosquitoes were collected from residences only. Results: A total 2,709 night students enrolled in the Program for Education of Young Adults (EJA), and 935 people registered in the residences near the schools were examined, being 641 from Porto Velho, 214 from Guajará-Mirim and 80 from Humaitá. No individual examined was positive for the presence of microfilariae in the blood stream. A total of 7,860 female Culex quinquefasciatus specimens examined were negative by PCR. Conclusions: This survey including human and mosquito examinations indicates that the western Amazon region of Brazil is not a focus of Bancroftian filariasis infection or transmission. Therefore, there is no need to be included in the Brazilian lymphatic filariasis control program.

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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.Keywords: Mansonella ozzardi. Microfilariae. Simuliidae. State of Rondônia. RESUMOIntrodução: 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. Palavras-chaves:Mansonella ozzardi. Microfilárias. Simuliidae. Rondônia.

The treatment of mansonelliasis is still a challenge because there are few clinical trials for the treatment of the disease. This double-blind, randomized, placebo-controlled study (phase III clinical trial) was conducted to evaluate the effectiveness of a single oral dose of ivermectin (0.15 mg/kg) in the reduction of the microfilaraemia and the occurrence of adverse effects in infected people compared with the control group treated with placebo. A total of 49 microfilaraemic patients were randomly selected from the municipality of Lábrea, State of Amazonas, in the Brazilian Amazon. Among them, 40 patients have concluded the study, 19 treated with ivermectin and 21 treated with placebo. In the first and third days after the treatment, all the patients were clinically evaluated, and the diagnostic and quantification of blood microfilariae through blood filtration in polycarbonate membranes was performed. A significant reduction of the microfilaraemia (99.9%) was observed in the patients who received ivermectin. Slight changes in laboratory test results, without clinical importance, were seen in treated and control groups. Our results suggest that ivermectin is effective and safe for the treatment of infections caused by.