IDT Biologika GmbH, Dessau-Rosslau, Germany.
PLoS One. 2013 Apr 22;8(4):e61597. doi: 10.1371/journal.pone.0061597. Print 2013.
Recent epidemiological developments demonstrated that gene segments of swine influenza A viruses can account for antigenic changes as well as reduced drug susceptibility of pandemic influenza A viruses. This raises questions about the efficacy of preventive measures against swine influenza A viruses. Here, the protective effect of vaccination was compared with that of prophylactic Tamiflu® treatment against two Eurasian swine influenza A viruses. 11-week-old pigs were infected by aerosol nebulisation with high doses of influenza virus A/swine/Potsdam/15/1981 (H1N1/1981, heterologous challenge to H1N1 vaccine strain) and A/swine/Bakum/1832/2000 (H1N2/2000, homologous challenge to H1N2 vaccine strain) in two independent trials. In each trial (i) 10 pigs were vaccinated twice with a trivalent vaccine (RESPIPORC® FLU3; 28 and 7 days before infection), (ii) another 10 pigs received 150 mg/day of Tamiflu® for 5 days starting 12 h before infection, and (iii) 12 virus-infected pigs were left unvaccinated and untreated and served as controls. Both viruses replicated efficiently in porcine respiratory organs causing influenza with fever, dyspnoea, and pneumonia. Tamiflu® treatment as well as vaccination prevented clinical signs and significantly reduced virus shedding. Whereas after homologous challenge with H1N2/2000 no infectious virus in lung and hardly any lung inflammation were detected, the virus titre was not and the lung pathology was only partially reduced in H1N1/1981, heterologous challenged pigs. Tamiflu® application did not affect these study parameters. In conclusion, all tested preventive measures provided protection against disease. Vaccination additionally prevented virus replication and histopathological changes in the lung of homologous challenged pigs.
最近的流行病学发展表明，猪流感 A 病毒的基因片段可以导致抗原变化以及大流行性流感 A 病毒的药物敏感性降低。这引发了对预防猪流感 A 病毒措施的有效性的质疑。在这里，比较了疫苗接种和预防性使用达菲®（Tamiflu®）治疗两种欧亚猪流感 A 病毒的效果。在两项独立的试验中，通过气溶胶雾化以高剂量感染猪流感病毒 A/swine/Potsdam/15/1981（H1N1/1981，对 H1N1 疫苗株的异源挑战）和 A/swine/Bakum/1832/2000（H1N2/2000，对 H1N2 疫苗株的同源挑战）。在每个试验中：（i）10 头猪用三价疫苗（RESPIPORC® FLU3；在感染前 28 天和 7 天接种两次）进行两次疫苗接种，（ii）另外 10 头猪在感染前 12 小时开始每天服用 150mg 的达菲®治疗 5 天，（iii）12 头感染病毒的猪未接种和未治疗，作为对照。两种病毒均在猪的呼吸道器官中有效复制，导致流感，出现发热、呼吸困难和肺炎。达菲®治疗和疫苗接种均可预防临床症状，并显著减少病毒脱落。尽管在 H1N2/2000 同源性挑战后，肺中的病毒载量和肺炎症几乎检测不到，但在 H1N1/1981 异源性挑战的猪中，病毒滴度没有降低，肺病理学也只有部分减轻。达菲®的应用并未影响这些研究参数。总之，所有测试的预防措施都提供了疾病保护。接种疫苗还可预防同源性挑战猪的肺部病毒复制和组织病理学变化。
