RESUMO
Fifteen bacterial isolates from spotted fever group rickettsiosis in Brazil were genetically identified as Rickettsia rickettsii. In a phylogenetic analysis with other R. rickettsii isolates from GenBank, the Central/South American isolates showed low polymorphism and formed a clade distinct from two North American clades, with the North American clades having greater in-branch polymorphism.
Assuntos
Polimorfismo Genético , Rickettsia rickettsii/classificação , Rickettsia rickettsii/genética , Febre Maculosa das Montanhas Rochosas/microbiologia , Brasil , Análise por Conglomerados , DNA Bacteriano/química , DNA Bacteriano/genética , Genótipo , Humanos , Dados de Sequência Molecular , Filogenia , Rickettsia rickettsii/isolamento & purificação , Análise de Sequência de DNA , Homologia de SequênciaRESUMO
Rickettsial spotted fever is common in southeastern Brazil. Differential diagnosis of pathogens can be performed with proper laboratory methods. A traveler arriving from Portugal developed a fatal febrile hemorrhagic syndrome diagnosed as spotted fever rickettsiosis. We isolated the agent, which was identified as Rickettsia conorii conorii by sequencing rickettsial genes.
Assuntos
Febre Botonosa , DNA Bacteriano , Genes Bacterianos , Rickettsia conorii , Análise de Sequência de DNA/métodos , Animais , Febre Botonosa/epidemiologia , Febre Botonosa/microbiologia , Febre Botonosa/transmissão , Brasil/epidemiologia , Reservatórios de Doenças/microbiologia , Cães , Evolução Fatal , Humanos , Masculino , Pessoa de Meia-Idade , Portugal , Rickettsia conorii/genética , Rickettsia conorii/isolamento & purificação , Rickettsia conorii/patogenicidade , Homologia de Sequência do Ácido Nucleico , Tempo para o Tratamento , Viagem , Zoonoses/epidemiologia , Zoonoses/microbiologia , Zoonoses/transmissãoRESUMO
Brazilian spotted fever (BSF) caused by Rickettsia rickettsii is the most important rickettsiosis and the only reportable tick-borne disease in Brazil. In Brazil, the hard tick Amblyomma cajennense is the most important BSF vector; however, in São Paulo State, A. aureolatum was also recognized as a vector species in remaining Atlantic forest areas near the metropolitan area of São Paulo city. We analyzed clinical and epidemiological features of BSF cases from two distinct areas where A. cajennense (Area 1) and A. aureolatum (Area 2) are the incriminated vectors. The clinical features demonstrate the same severity pattern of BSF in both endemic areas. Differences in seasonality, patient characteristics (median age and gender), and epidemiological risk factors (animals host contact and vegetation characteristics) were observed and possibly could be attributed to the characteristics of each vector and their typical biological cycle (hosts and environment).
Assuntos
Doenças Endêmicas , Rickettsia rickettsii/isolamento & purificação , Febre Maculosa das Montanhas Rochosas/epidemiologia , Febre Maculosa das Montanhas Rochosas/patologia , Adolescente , Adulto , Idoso , Animais , Brasil/epidemiologia , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Ixodidae/microbiologia , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco , Índice de Gravidade de Doença , Adulto JovemRESUMO
A descriptive, entomological and seroepidemiological study on Chagas disease was conducted in a place of recent occupation on the outskirts of Cochabamba, Bolivia: Avaroa/Primer de Mayo (population: 3.000), where the socio-economic level is low no control measures have been made available. Methods - The immunofluorescent antibody test (IFAT) was used for IgG and IgM anti-Trypanosoma cruzi antibodies in filter paper bloodspot eluates from 128 subject age, gender, birthplace, occupation, duration of residence and building materials used in their houses were recorded. Vectors were captured both in domestic and peridomestic environments. Results - Seropositive, 12,5 per cent (16/128): females, 15.1 per cent (11/73); males, 9.1 per cent (5/55). Average time of residence: 6.1 years for the whole population sample and 7.4 years for the seropositive subjects. Most houses had abobe walls (76.7 per cent, n = 30), galvanized iron rooves (86.7 per cent) and earthen floors (53.4 per cent) 80 per cent of the walls had crevices. One hundred forty seven specimens of Triatoma infestans were captured, of which 104 (70.7 per cent) were domestic, and 1 peridomestic Triatoma sordida. Precipitin host identification: birds, 67.5 per cent; humans, 27.8 per cent; rodents, 11.9 per cent; dogs, 8.7 per cent; cats, 1.6 per cent. House infestation and density indices were 53.3 and 493.0 respectively. We found 21 (14.3 per cent) specimens of T. infestans infected with trypanosomes, 18 (85.7 per cent) of which domestic environments. Discussion - The elements for the vector transmission of Chagas disease are present in Avaroa/Primer de Mayo and the ancient custom of keeping guinea pigs indoors adds to the risk of human infection. In neighboring Cochabamba, due to sub-standard quality control, contaminated blood transfusions are not infrequent, which further aggravates the spread of Chagas disease. Prompt action to check the transmission of this infection, involving additionally the congenital and transfusional modes of acquisition, is required.
Assuntos
Humanos , Feminino , Gatos , Cães , Animais , Criança , Pré-Escolar , Lactente , Pessoa de Meia-Idade , Adulto , Adolescente , Doença de Chagas/epidemiologia , Roedores , Triatoma/parasitologia , Trypanosoma cruzi/imunologia , População Urbana , Bolívia/epidemiologia , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Anticorpos Antiprotozoários/sangue , Estudos Soroepidemiológicos , Doença de Chagas/diagnóstico , Doença de Chagas/transmissão , Técnica Indireta de Fluorescência para Anticorpo , Vetores de DoençasRESUMO
After the realization of control research that had in view the transmission of dengue virus, we started to monitor two kinds of entomological vigilance, Breteau Index and ovitrap. We intended to evaluate the necessary time elapsed before Aedes sp mosquitoes were again detected at the urban area of Catanduva s town (SP). The ovitraps showed positiveness for the Aedes aegypti two months after the control research, while the Breteau Index became positive only at the fourth month after the end of the referred research.