Shandong Provincial Center for Disease Prevention and Control, Jinan, China.
Binzhou Center for Disease Prevention and Control, Binzhou, China.
BMC Infect Dis. 2024 Jun 1;24(1):550. doi: 10.1186/s12879-024-09441-7.
Influenza A virus infections can occur in multiple species. Eurasian avian-like swine influenza A (H1N1) viruses (EAS-H1N1) are predominant in swine and occasionally infect humans. A Eurasian avian-like swine influenza A (H1N1) virus was isolated from a boy who was suffering from fever; this strain was designated A/Shandong-binzhou/01/2021 (H1N1). The aims of this study were to investigate the characteristics of this virus and to draw attention to the need for surveillance of influenza virus infection in swine and humans.
Throat-swab specimens were collected and subjected to real-time fluorescent quantitative polymerase chain reaction (RT‒PCR). Positive clinical specimens were inoculated onto Madin-Darby canine kidney (MDCK) cells to isolate the virus, which was confirmed by a haemagglutination assay. Then, whole-genome sequencing was carried out using an Illumina MiSeq platform, and phylogenetic analysis was performed with MEGA X software.
RT‒PCR revealed that the throat-swab specimens were positive for EAS-H1N1, and the virus was subsequently successfully isolated from MDCK cells; this strain was named A/Shandong-binzhou/01/2021 (H1N1). Whole-genome sequencing and phylogenetic analysis revealed that A/Shandong-binzhou/01/2021 (H1N1) is a novel triple-reassortant EAS-H1N1 lineage that contains gene segments from EAS-H1N1 (HA and NA), triple-reassortant swine influenza H1N2 virus (NS) and A(H1N1) pdm09 viruses (PB2, PB1, PA, NP and MP).
The isolation and analysis of the A/Shandong-binzhou/01/2021 (H1N1) virus provide further evidence that EAS-H1N1 poses a threat to human health, and greater attention should be given to the surveillance of influenza virus infections in swine and humans.
甲型流感病毒可感染多种物种。欧亚类禽源性甲型 H1N1 流感病毒（EAS-H1N1）在猪群中流行，偶尔感染人类。从一名发热的男孩中分离到一株欧亚类禽源性甲型 H1N1 流感病毒，被命名为 A/山东滨州/01/2021（H1N1）。本研究旨在分析该病毒的特征，并提醒人们关注猪群和人群中流感病毒感染的监测。
采集咽拭子标本，采用实时荧光定量聚合酶链反应（RT-PCR）检测。对阳性临床标本进行接种，接种于 Madin-Darby 犬肾（MDCK）细胞中分离病毒，血凝试验鉴定。然后，采用 Illumina MiSeq 平台进行全基因组测序，并采用 MEGA X 软件进行系统进化分析。
RT-PCR 显示咽拭子标本 EAS-H1N1 阳性，MDCK 细胞中成功分离到病毒，将其命名为 A/山东滨州/01/2021（H1N1）。全基因组测序和系统进化分析显示，A/山东滨州/01/2021（H1N1）为新型三重重配 EAS-H1N1 谱系，包含 EAS-H1N1（HA 和 NA）、三重重配猪源 H1N2 病毒（NS）和 A（H1N1）pdm09 病毒（PB2、PB1、PA、NP 和 MP）的基因片段。
A/山东滨州/01/2021（H1N1）病毒的分离和分析进一步表明，EAS-H1N1 对人类健康构成威胁，应更加关注猪群和人群中流感病毒感染的监测。
