Department of Microbiology, School of Medicine, Universitas Airlangga, Surabaya, East Java, Indonesia.
Master Program of Tropical Medicine, School of Medicine, Universitas Airlangga, Surabaya, East Java, Indonesia.
J Med Virol. 2019 Jun;91(6):1048-1055. doi: 10.1002/jmv.25403. Epub 2019 Feb 1.
Outbreaks of hepatitis A have occurred in some cities in Indonesia. In Surabaya, the capital city of East Java province, Indonesia, hepatitis A outbreaks have been reported since2013, with a marked increase in the number of cases in 2015. The aim of the present study was to analyze the genetic and serology of acute symptomatic cases (early infection) during a hepatitis A outbreak and asymptomatic cases after the outbreak in two junior high schools in Surabaya in 2015 to 2016. Students with acute symptomatic hepatitis A during the outbreak and other students who were asymptomatic 3 to 4 months after the outbreak were enrolled. Asymptomatic students had no symptoms from the outbreak until they were enrolled. Sera were collected to identify anti-hepatitis A virus (HAV) IgM (by enzyme-linked immunosorbent assay) and HAV genetic variations/genotypes (using polymerase chain reaction [PCR]-sequencing and phylogenetic analysis). A total of 33 (97.1%) out of 34 sera of students with acute symptoms were positive for anti-HAV IgM and 18% of them were positive by PCR, identified as HAV subgenotype IA. No prominent amino acid variations were observed from reported HAV sequences from Indonesia. Among 38 sera of asymptomatic students, most (55.3%) were positive for anti-HAV IgM, while none were positive by PCR. In conclusion, HAV-IA was the only subgenotype identified in acute symptomatic cases during the outbreak. The percentage of HAV-specific IgM-positive cases was very high among acute symptomatic students, but that was also high among asymptomatic students, which might contribute as the important source of infection during the outbreak.
印度尼西亚的一些城市发生了甲型肝炎疫情。在印度尼西亚东爪哇省首府泗水，自 2013 年以来报告了甲型肝炎疫情，2015 年病例数明显增加。本研究旨在分析 2015 年至 2016 年泗水两所初中爆发期间急性症状病例（早期感染）和爆发后无症状病例的遗传和血清学特征。招募了爆发期间患有急性症状性甲型肝炎的学生和爆发后 3 至 4 个月无症状的其他学生。无症状学生从爆发开始到入组时均无症状。收集血清以鉴定抗甲型肝炎病毒（HAV）IgM（通过酶联免疫吸附试验）和 HAV 遗传变异/基因型（使用聚合酶链反应[PCR]-测序和系统发育分析）。在 34 份急性症状学生血清中，共有 33 份（97.1％）抗 HAV IgM 阳性，其中 18％通过 PCR 阳性，鉴定为 HAV 亚基因型 IA。未观察到从印度尼西亚报告的 HAV 序列中存在明显的氨基酸变异。在 38 份无症状学生血清中，大多数（55.3％）抗 HAV IgM 阳性，而 PCR 均为阴性。总之，在疫情期间仅鉴定出急性症状病例中的 HAV-IA 亚基因型。在急性症状学生中，HAV 特异性 IgM 阳性病例的比例非常高，但在无症状学生中也很高，这可能是疫情期间的重要感染源。
