National Veterinary Institute, (SVA), Ulls väg 2B, SE-751 89 Uppsala, Sweden.
Virol J. 2009 Oct 28;6:180. doi: 10.1186/1743-422X-6-180.
The European swine influenza viruses (SIVs) show considerable diversity comprising different types of H1N1, H3N2, and H1N2 strains. The intensifying full genome sequencing efforts reveal further reassortants within these subtypes. Here we report the identification of an uncommon reassortant variant of H1N2 subtype influenza virus isolated from a pig in a multisite herd where H1N2 swine influenza was diagnosed for the first time in Sweden during the winter of 2008-2009. The majority of the European H1N2 swine influenza viruses described so far possess haemagglutinin (HA) of the human-like H1N2 SIV viruses and the neuraminidase (NA) of either the European H1N2 or H3N2 SIV-like viruses. The Swedish isolate has an avian-like SIV HA and a H3N2 SIV-like NA, which is phylogenetically more closely related to H3N2 SIV NAs from isolates collected in the early '80s than to the NA of H3N2 origin of the H1N2 viruses isolated during the last decade, as depicted by some German strains, indicative of independent acquisition of the NA genes for these two types of reassortants. The internal genes proved to be entirely of avian-like SIV H1N1 origin. The prevalence of this SIV variant in pig populations needs to be determined, as well as the suitability of the routinely used laboratory reagents to analyze this strain.The description of this H1N2 SIV adds further information to influenza epidemiology and supports the necessity of surveillance for influenza viruses in pigs.
欧洲猪流感病毒（SIV）表现出相当大的多样性，包括不同类型的 H1N1、H3N2 和 H1N2 株。加强全基因组测序工作揭示了这些亚型内进一步的重配体。在这里，我们报告了一种罕见的 H1N2 亚型流感病毒重组变体的鉴定，该病毒是从一个多地点牛群中的一头猪中分离出来的，该牛群在 2008-2009 年冬季首次在瑞典诊断出 H1N2 猪流感。迄今为止，描述的大多数欧洲 H1N2 猪流感病毒具有类似于人类的 H1N2 SIV 病毒的血凝素（HA）和欧洲 H1N2 或 H3N2 SIV 样病毒的神经氨酸酶（NA）。瑞典分离株具有类似于禽类的 SIV HA 和类似于 H3N2 的 SIV NA，在系统进化上与 80 年代早期收集的 H3N2 SIV NAs 更为密切相关，而与过去十年中分离的 H1N2 病毒的 H3N2 起源的 NA 则不太相关，这表明这两种类型的重配体的 NA 基因是独立获得的。内部基因被证明完全是类似于禽类的 SIV H1N1 起源。需要确定这种 SIV 变体在猪群中的流行程度，以及常规实验室试剂分析这种菌株的适用性。这种 H1N2 SIV 的描述增加了流感流行病学的信息，并支持对猪流感病毒进行监测的必要性。
