Virology Unit, The Irish Equine Centre, Johnstown, Naas, Co., Kildare, Ireland.
Vaccine. 2011 Nov 15;29(49):9214-23. doi: 10.1016/j.vaccine.2011.09.101. Epub 2011 Oct 5.
Many racing authorities, sales companies and equestrian bodies have mandatory vaccination policies for equine influenza (EI). The consequences of lack of vaccine efficacy include clinical disease, disruption to training programmes, the cancellation of equestrian events and the introduction of virus to susceptible populations. The correlation between antibody against the virus haemagglutinin and protection against influenza has been well established. The objective of this study was to compare the antibody responses of 66 unvaccinated Thoroughbred weanlings on four different stud farms, following primary vaccination (V1, V2 and V3) with the five EI vaccines commercially available in Ireland (Duvaxyn IET Plus, Equilis Resequin, Equip FT, Equilis Prequenza Te, ProteqFlu Te). Antibody responses were monitored for 6 months post V3 by single radial haemolysis. The pattern of antibody response was similar for all vaccines and for all antigens tested. A rapid decline of antibody level was observed by 3 months post V2 for all vaccines. The antibody response of the horses vaccinated with the whole virus vaccine Duvaxyn IET Plus was significantly higher than that of the horses vaccinated with the other four products. Five weanlings had maternally derived antibodies (MDA) at the time of V1. The canary pox recombinant vaccine, subunit vaccine and whole virus inactivated vaccines administered to these weanlings did not induce a detectable antibody response against the background of MDA but effectively primed the animals as revaccination resulted in a strong antibody response. In this study 43% of the weanlings failed to seroconvert after V1. This high incidence of poor responders has not been reported in previous experimental studies relating to these products. The poor responders were observed in all vaccine groups except those vaccinated with Duvaxyn IET Plus. Post V2 the incidence of poor responders was reduced to 7% and all horses responded to V3. The study demonstrates that independent evaluation of influenza vaccine performance in the field is critical to add to the body of knowledge gained from experimental challenge experiments carried out for regulatory or marketing purposes.
许多赛马管理机构、销售公司和马术团体都对马流感（EI）实施强制性疫苗接种政策。疫苗效力不足的后果包括临床疾病、训练计划中断、马术赛事取消以及病毒传播给易感人群。病毒血凝素抗体与流感保护之间的相关性已得到充分证实。本研究的目的是比较 66 匹未接种疫苗的纯种断奶驹在接种商业上可获得的五种爱尔兰 EI 疫苗（Duvaxyn IET Plus、Equilis Resequin、Equip FT、Equilis Prequenza Te、ProteqFlu Te）后的首次接种（V1、V2 和 V3）后的抗体反应。在 V3 后 6 个月通过单径向溶血监测抗体反应。所有疫苗和所有测试抗原的抗体反应模式相似。所有疫苗在 V2 后 3 个月内抗体水平迅速下降。接种全病毒疫苗 Duvaxyn IET Plus 的马的抗体反应明显高于接种其他四种产品的马。在 V1 时，有 5 匹断奶驹具有母源抗体（MDA）。这些断奶驹接种的禽痘重组疫苗、亚单位疫苗和全病毒灭活疫苗在 MDA 的背景下未诱导出可检测到的抗体反应，但有效地对动物进行了启动，因为再次接种导致强烈的抗体反应。在这项研究中，43%的断奶驹在 V1 后未能血清转化。与这些产品相关的先前实验研究中没有报道过这种高比例的低应答者。除了接种 Duvaxyn IET Plus 的断奶驹外，所有疫苗组都观察到低应答者。在 V2 后，低应答者的发生率降低到 7%，所有马都对 V3 有反应。该研究表明，独立评估流感疫苗在现场的性能对于增加从监管或营销目的进行的实验性挑战实验中获得的知识体系至关重要。
