Moa Aye M, Muscatello David J, Turner Robin M, MacIntyre Chandini R
School of Public Health and Community Medicine, University of New South Wales, Sydney, NSW, Australia.
College of Public Service & Community Solutions, Arizona State University, Phoenix, Arizona, USA.
Influenza Other Respir Viruses. 2017 Mar;11(2):102-109. doi: 10.1111/irv.12432. Epub 2016 Oct 14.
Influenza B is characterised by two antigenic lineages: B/Victoria and B/Yamagata. These lineages circulate together with influenza A during influenza seasons, with varying incidence from year to year and by geographic region.
To determine the epidemiology of influenza B relative to influenza A in Australia.
Laboratory-confirmed influenza notifications between 2001 and 2014 in Australia were obtained from the Australian National Notifiable Diseases Surveillance System.
A total of 278 485 laboratory-confirmed influenza cases were notified during the study period, comprising influenza A (82.2%), B (17.1%) and 'other and untyped' (0.7%). The proportion of notifications that were influenza B was highest in five- to nine-year-olds (27.5%) and lowest in persons aged 85 years and over (11.5%). Of all B notifications with lineage determined, 77.1% were B/Victoria and 22.9% were B/Yamagata infections. Mismatches between the dominant B lineage in a season and the trivalent vaccine B lineage occurred in over one-third of seasons during the study years. In general, influenza B notifications peaked later than influenza A notifications.
The proportion of circulating influenza B in Australia during 2001-2014 was slightly lower than the global average and was dominated by B/Victoria. Compared with influenza A, influenza B infection was more common among older children and young adults and less common in the very elderly. Influenza B lineage mismatch with the trivalent vaccine occurred about one-third of the time.
乙型流感由两个抗原谱系组成：B/维多利亚系和B/山形系。在流感季节，这些谱系与甲型流感一起传播，每年的发病率以及不同地理区域的发病率各不相同。
确定澳大利亚乙型流感相对于甲型流感的流行病学特征。
从澳大利亚国家法定传染病监测系统获取2001年至2014年澳大利亚实验室确诊的流感报告。
在研究期间共报告了278485例实验室确诊的流感病例，其中甲型流感占82.2%，乙型流感占17.1%，“其他及未分型”占0.7%。五岁至九岁儿童中乙型流感报告比例最高（27.5%），85岁及以上人群中比例最低（11.5%）。在所有已确定谱系的乙型流感报告中，77.1%为B/维多利亚系感染，22.9%为B/山形系感染。在研究年份中，超过三分之一的季节里，某一季节占主导地位的乙型流感谱系与三价疫苗中的乙型流感谱系不匹配。总体而言，乙型流感报告的高峰期晚于甲型流感报告。
2001年至2014年期间，澳大利亚乙型流感的传播比例略低于全球平均水平，且以B/维多利亚系为主。与甲型流感相比，乙型流感感染在大龄儿童和年轻人中更为常见，在老年人中则较少见。乙型流感谱系与三价疫苗不匹配的情况约占三分之一。
