Caracterização molecular enterovĺrus detectados em crianças com diarreia aguda e amostras ambientais em Moçambique
Molecular characterization of enteroviruses detected in children with acute diarrhea and environmental samples in Mozambique
Ano de publicação: 2020
Teses e dissertações em Português apresentado à Instituto oswaldo cruz. Programa de pós-graduação em medicina tropical para obtenção do título de Doutor. Orientador: da Silva, Edson Elias
Os enterovírus (EV) são vírus de transmissão predominantemente entérica, presentes em todas as partes do mundo e são agentes etiológicos de infecções que variam de casos assintomáticos a casos de gastroenterite aguda (GA) e infecções no sistema nervoso central. Devido aos diferentes rumos que as infecções por esses microrganismos podem tomar no organismo, as vigilâncias epidemiológica e ambiental dos EV são importantes ferramentas para definição de políticas públicas de prevenção e controle. O objetivo deste estudo foi detectar e caracterizar EV em amostras clínicas e ambientais coletadas em Moçambique entre 2014 e 2018. Foram realizados dois estudos, um em casos de diarreia e outro em aguas de esgoto. No estudo de casos de diarreia, 327 amostras de fezes de crianças menores de cinco anos, internadas com GA entre junho de 2014 e março de 2018 em unidades de saúde das províncias de Maputo, Nampula, Sofala e Zambézia foram estudadas. As amostras foram testadas por RT-PCR em tempo real, inoculadas em cultivo celular (RD e HEp2C) e os tipos de EV foram identificados por sequenciamento nucleotídico. A frequência dos EV detectados foi de 15,9% (52/327) das amostras. A faixa etária dos 12 a 23 meses foi a mais afetada (p
Enteroviruses (EV) are enteric pathogens showing global distribution and are etiologic agents of infections ranging from asymptomatic cases to cases of acute gastroenteritis (AGE) and infections in the central nervous system. Due to different clinical effects of that EV infection in the organism, active surveillance system is relevant to provide important information and support to public health policies for prevention and control. The purpose of this study was to characterize EV infection in clinical and environmental samples collected in Mozambique between 2014 and 2018. Two studies were carried out, one in cases of diarrhea and the other in sewage. In the study of cases of diarrhea, 327 fecal samples from children less than 5 years old hospitalized with AGE in health care units in Maputo, Nampula, Sofala and Zambézia provinces from Mozambique between June 2014 and March 2018. Samples were tested by real-time RT-PCR, viral isolation (RD and HEp2C) and subsequent nucleotide sequence of types. Overall, the frequency of EV positive was 15.9% (52/327). The age group from 12 to 23 months was the most affected (p<0.045). Higher positivity of enteroviruses was found in samples with negative results for other enteric pathogens (p<0.011). Enterovírus B was the most prevalent species (40.4%), followed by Enterovírus C with (32.7%) and finally Enterovírus A with (26.9%). Twenty-six types of enteroviruses were detected, and EV-A11 and EV-C99 serotypes the most frequent (17.3% and 15.4, respectively). The EV AGE cases were severe, especially in the 12 to 23-month aged range, with a longer duration of symptoms and hospitalization. Co-detection between enterovírus and other agents was found in 17.3% (09/52). Temperature was positively correlated with enterovirus infection (p<0. 006). For the environmental surveillance, sewage samples were collected in the city of Maputo, Mozambique, between January and November 2018. Viral concentration was performed by the silica absorption method and concentrates were inoculated in the RD and L20B cell lines for viral isolation, followed by RT-PCR analysis and subsequent nucleotide sequencing. Of the 63 analyzed samples, 25 (39.7%) were positive for enterovirus, with a high frequency of Enterovirus B species (96%)…