RESUMO
A regional epidemic of aseptic meningitis caused by echovirus 30 (E30) occurred in Hokkaido, Japan, during the period of August-December 2017. To investigate their phylogenetic relationship to other human enteroviruses, we determined the complete genomic nucleotide sequences of isolates from this outbreak. Phylogenetic analysis of the viral capsid protein 1 gene showed that the strains were most closely related to E30 strains detected in Germany, France, and Russia in 2013. In contrast, the region encoding the viral protease and the RNA-dependent RNA polymerase had a close phylogenetic relationship to non-E30 enteroviruses detected in the United Kingdom and Switzerland in 2015-2017, suggesting that a recombination event had occurred.
Assuntos
Infecções por Echovirus/virologia , Enterovirus Humano B/genética , Meningite Asséptica/virologia , Proteínas do Capsídeo/genética , Surtos de Doenças , Infecções por Enterovirus/virologia , Epidemias , França , Genótipo , Alemanha , Humanos , Japão , Epidemiologia Molecular/métodos , Filogenia , RNA Viral/genética , Federação Russa , Análise de Sequência de DNA/métodos , Suíça , Reino UnidoRESUMO
BACKGROUND: Echovirus 30 (E30) is one of the most common causative agents for aseptic meningitis. OBJECTIVES: In the autumn of 2017, there was an outbreak caused by E30 in Kushiro, Hokkaido, Japan. The aim of this study was to characterize this outbreak. STUDY DESIGN: Fifty-nine patients were admitted to the Department of Pediatrics, Kushiro Red Cross Hospital (KRCH) with clinical diagnosis of aseptic meningitis. Among those, 36 patients were finally diagnosed as E30-associated aseptic meningitis by the detection of viral RNA using reverse transcription-polymerase chain reaction (RT-PCR) and/or the evidence of more than four-fold rise in neutralizing antibody (NA) titers in the convalescent phase relative to those in the acute phase. We investigated these 36 confirmed cases. RESULTS: The median age was 6 years (range: 6 months-14 years). The positive signs and symptoms were as follows: fever (100%), headache (94%), vomiting (92%), jolt accentuation (77%), neck stiffness (74%), Kernig sign (29%), and abdominal pain (28%). The median cerebrospinal fluid (CSF) white cell count, neutrophil count, and lymphocyte count were 222/µL (range: 3-1434/µL), 144/µL (range: 1-1269/µL), and 85/µL (range: 2-354/µL), respectively. Although the detected viral genes demonstrated same cluster, they were different from E30 strains observed in Japan between 2010 and 2014. CONCLUSION: We mainly showed clinical and virological features of the E30-associated aseptic meningitis outbreak that occurred in Kushiro. To prevent further spread of E30 infection, continuous surveillance of enterovirus (EV) circulation and standard precautions are considered essential.
Assuntos
Surtos de Doenças , Infecções por Echovirus/epidemiologia , Infecções por Echovirus/virologia , Enterovirus Humano B/isolamento & purificação , Meningite Asséptica/epidemiologia , Meningite Asséptica/virologia , Adolescente , Anticorpos Neutralizantes/sangue , Líquido Cefalorraquidiano/citologia , Criança , Pré-Escolar , Infecções por Echovirus/patologia , Infecções por Echovirus/fisiopatologia , Enterovirus Humano B/classificação , Enterovirus Humano B/genética , Enterovirus Humano B/imunologia , Feminino , Genótipo , Hospitais Pediátricos , Humanos , Lactente , Japão/epidemiologia , Masculino , Meningite Asséptica/patologia , Meningite Asséptica/fisiopatologia , Filogenia , RNA Viral/genética , Proteínas Virais/genéticaRESUMO
BACKGROUND: Infection with hepatitis E virus (HEV) genotypes 3 and 4 are usually asymptomatic but can occasionally result in life-threatening acute hepatitis. To date, only sporadic cases together with a few outbreaks have been documented. Seroprevalence studies with assays for the detection of HEV IgG antibodies, suggest that HEV is more prevalent than previously thought, even in non-endemic regions. OBJECTIVES: The aim of this study was to characterize an outbreak of hepatitis E (HE) in a nursing home for aged people between February and March 2016. STUDY DESIGN: After the identification of two cases living in the same nursing home, the presence of antibodies against HEV and HEV RNA were examined in serum samples collected from the other residents and staff members to identify any additional cases. An epidemiological investigation was also carried out. RESULTS: Only 4 patients showed mild symptoms such as anorexia, abdominal pain and fatigue. Among the 125 persons tested, 28 residents and one dietitian were confirmed positive for anti-HEV IgA or IgM antibodies, and/or HEV RNA. Eight samples had only IgG antibodies. Finally, 22 cases were notified with HE on the basis of the presence of IgA antibodies. All HEV isolates obtained were 99.8-100% identical and belonged to genotype 3. CONCLUSION: HEV infections seem to be under-reported or underestimated possibly due to cases being generally asymptomatic. Testing for the presence of both anti-HEV antibodies and HEV RNA would be beneficial for both the comprehensive diagnosis of HE infections and the prevention of further infections.