The aim of this study was to determine the prevalence of malaria infection and antibodies against the repetitive epitopes of the circumsporozoite (CS) proteins of Plasmodium falciparum, P. malariae, P. vivax VK210, P. vivax VK247, and P. vivax-like in individuals living in the states of Rondônia, Pará, Mato Grosso, Amazonas, and Acre. Active malaria transmission was occurring in all studied sites, except in Acre. P. falciparum was the predominant species in Pará and Rondônia and P. vivax in Mato Grosso. Infection by P. malariae was low but this Plasmodium species was detected in Rondônia (3.5%), Mato Grosso (2.5%), and Pará (0.8%). High prevalence and levels of serological reactivity against the CS repeat peptides of P. falciparum were detected in Rondônia (93%) and Pará (85%). Sera containing antibodies against the CS repeat of P. malariae occurred more frequently in Rondônia (79%), Pará (76%), and Amazonas (68%). Antibodies against the repeat epitope of the standard CS protein of P. vivax VK210, P. vivax VK247, and P. vivax-like were more frequent in Rondônia, Pará, and Mato Grosso. The high frequency of reactions to P. malariae in most of the areas suggests that the infection by this Plasmodium species has been underestimated in Brazil. Key words: Plasmodium -infection -Amazon region -BrazilMalaria remains as a serious health problem in the Amazon Basin of Brazil and approximately 99% of some 600,000 cases notified annually occur in this region (Ministério da Saúde 2003, Coura et al. 2006. Malaria is heterogeneously distributed in the nine states of the Legal Amazon and the number of annual cases fluctuates, increasing in some states where gold mining activities take place, massive migration occurs, and new settlements projects are implemented. However, the states of Pará, Amazonas, and Rondônia are always among the major malaria-endemic regions. Based on microscopic examination from the records of the Brazilian Ministry of Health, P. falciparum and P. vivax are the most prevalent Plasmodium. The reported prevalence of P. malariae is very low (< 1%). In the last 15 years the number of P. vivax has increased and presently accounts for 78% of all malaria cases reported in the country. Besides the classic P. vivax VK210, two species-specific circumsporozoite (CS) protein variants P. vivax VK247 (Rosenberg et al. 1989) and P. vivax-like (Qari et al. 1993, 1994 were described. The human P. vivax-like parasite has a CS repeat which corresponds to the simian parasite P. simiovale. Otherwise the identity of these parasites is not clear, since a line of the human isolates has not yet been obtained and the clinical manifestation of these infections is unknown.Antibodies to sporozoites represent a serological transmission indicator and have been used in epidemiological studies to estimate the level of malaria in endemic areas. It is well known that individuals living in malaria endemic areas exposed to sporozoite infections develop antibodies directly to the repetitive epitopes of the CS protein. The prevalence and le...

Background Brazil has the fourth highest prevalence of malaria of all countries in the Americas, with an estimated 42 million people at risk of contracting this disease. Although most cases occur in the Amazon region, cases of an autochthonous nature have also been registered in the extra-Amazonian region where Anopheles aquasalis and An. albitarsis are the mosquito species of greatest epidemiological interest. In 2019, the municipality of Conde (state of Paraíba) experienced an epidemic of autochthonous cases of malaria. Here we present preliminary results of an entomological and case epidemiology investigation, in an attempt to correlate the diversity and spatial distribution of species of Anopheles with the autochthonous cases of this outbreak of malaria. Methods Case data were collected using case report forms made available by the Conde Municipal Health Department. The entomological survey was carried out from July to November 2019. The various methods of capture included the use of battery-powered aspirators, mouth aspirators, Shannon traps, BG-Sentinel traps (with and without dry ice) and CDC light traps. Captured mosquitoes were separated, packaged and sent to the laboratory for sexing and molecular identification of the various species of anophelines. The data were tabulated and analyzed using Microsoft Excel. Spatial analysis of the data was performed using ArcGis 10 software. Results In 2019, 20 autochthonous cases and one imported case of malaria caused by Plasmodium vivax were diagnosed, with three cases of relapses. A total of 3713 mosquitoes were collected, of which 3390 were culicines and 323 were anophelines. Nine species of genus Anopheles were identified, with the most abundant being An. aquasalis (38.9%), followed by An. minor (18.2%) and An. albitarsis (9.0%). Spatial analysis of the data showed that the area could be considered to be at risk of malaria cases and that there was a high prevalence of Anopheles. Conclusions The results presented indicate that this extra-Amazonian region has an environment conducive to maintenance of the malaria transmission cycle owing to the wide diversity of Anopheles species. This environment in combination with the high influx of people from endemic areas to the study area provides a perfect setting for the occurrence and maintenance of malaria.

RESUMO A caracterização protéica dos extratos de larvas infectantes (L3) de Wuchereria bancrofti foi realizada por eletroforese em gel de poliacrilamida, em presença de dodecil sulfato de sódio (SDS-PAGE) e o reconhecimento antigênico das proteínas por Western-blot. O maior número de bandas protéicas reconhecidas foi evidenciado nos extratos AgSE (105, 100, 76, 55, 49, 39 e 32 kDa) e AgS (100, 76, 55, e 49 kDa) (105, 100, 76, 55, 49, 39 and 32 kDa) A filariose linfática é causada pelo nematóide Wuchereria bancrofti e é transmitida ao homem pelo mosquito Culex quinquefasciatus. A forma evolutiva do parasita de maior importância no contexto imunológico é a larva de terceiro estádio (L3), pois representa a forma infectante que dissemina a parasitose e o primeiro contato do parasita com o hospedeiro definitivo. Pouco se conhece sobre suas características biológicas, antigênicas, aspectos moleculares e mesmo sobre as relações que se estabelecem entre hospedeiro-parasita, seja homem infectado e Wuchereria bancrofti, seja entre vetor e parasita.Na falta de um modelo animal experimental, para W. bancrofti, as informações que se possuem sobre a ação de larvas infectantes em seus hospedeiros mamíferos, referem-se a

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