Division of Virology, Department of Microbiology and Immunology, Institute of Medical Science, University of Tokyo, Tokyo 108-8639, Japan.
Department of Pathobiological Sciences, School of Veterinary Medicine, University of Wisconsin-Madison, Madison, WI 53711, USA.
Viruses. 2020 Jan 29;12(2):155. doi: 10.3390/v12020155.
The A(H1N1)pdm09 virus emerged in 2009 and continues to circulate in human populations. Recent A(H1N1)pdm09 viruses, that is, A(H1N1)pdm09 viruses circulating in the post-pandemic era, can cause more or less severe infections than those caused by the initial pandemic viruses. To evaluate the changes in pathogenicity of the A(H1N1)pdm09 viruses during their continued circulation in humans, we compared the nucleotide and amino acid sequences of ten A(H1N1)pdm09 viruses isolated in Japan between 2009 and 2015, and experimentally infected mice with each virus. The severity of infection caused by these Japanese isolates ranged from milder to more severe than that caused by the prototypic pandemic strain A/California/04/2009 (CA04/09); however, specific mutations responsible for their pathogenicity have not yet been identified.
2009 年出现了 A(H1N1)pdm09 病毒，该病毒至今仍在人类中传播。与最初的大流行病毒相比，近期的 A(H1N1)pdm09 病毒（即大流行后流行时期的 A(H1N1)pdm09 病毒）可引起或多或少严重的感染。为了评估 A(H1N1)pdm09 病毒在人类中持续传播过程中的致病性变化，我们比较了 2009 年至 2015 年期间在日本分离的 10 株 A(H1N1)pdm09 病毒的核苷酸和氨基酸序列，并分别用每种病毒感染实验小鼠。这些日本分离株引起的感染严重程度比原型大流行株 A/California/04/2009（CA04/09）引起的感染更为轻至重不等；但是，其致病性的确切突变尚未确定。
