Marenzoni Maria Luisa, De Waure Chiara, Timoney Peter J
Department of Veterinary Medicine, University of Perugia, Perugia, Italy.
Department of Medicine and Surgery, University of Perugia, Perugia, Italy.
Equine Vet J. 2023 May;55(3):389-404. doi: 10.1111/evj.13870. Epub 2022 Aug 31.
Equid herpesvirus type 1 (EHV-1) infection can cause a range of disease syndromes of variable severity that can result in a lethal outcome and restriction of horse movements, especially in the case of outbreaks involving neurological disease. Vaccination is one of the tools used to control the infection. It is widely known that vaccination is not completely effective in ensuring protection against disease caused by this virus. In fact, the real efficacy of vaccination against EHV-1 related disease has not been measured and no systematic reviews exist on this topic.
To perform a systematic review and meta-analysis on the efficacy of commercial or candidate vaccines against EHV-1 in randomised controlled trials (RCT) all of which involved experimental challenge of the test subjects.
Systematic review and meta-analysis.
RCTs were searched using the search algorithm (([equid herpesvirus* OR equine herpesvirus* OR EHV-1]) AND vaccin*) AND (trial OR experimental OR challenge) on PubMed, Science Citation Index Expanded, Scopus, and CAB Abstracts. Where appropriate, meta-analysis was performed using RevMan 5.4.
Eight studies were selected and were analysed for their respective characteristics and possible shortcomings. The results of RCTs revealed that there was a general improvement in the clinical and virological outcomes of EHV-1 infection following vaccination, but that the effects were very slight. The reduced beneficial effect is probably amplified by the paucity of detailed data reported in the studies that did not allow for the comparison of parameters in many of the cases analysed.
The remarkable heterogeneity and the poor quality of reporting of the selected studies.
Meta-analysis has shown that EHV-1 vaccination generally results in a slight improvement in clinical and virological outcomes, although not to a significant extent. The cumulative results have probably been affected by the lack of information on some parameters not systematically reported in the studies. An improvement in the standard of reporting and better standardisation of the data collected would likely have improved the quality of each study and enabled more effective comparison of the studies with each other.
1型马疱疹病毒（EHV - 1）感染可引发一系列严重程度各异的疾病综合征，可能导致致命后果并限制马匹移动，尤其是在涉及神经系统疾病的疫情爆发时。疫苗接种是控制该感染的手段之一。众所周知，疫苗接种在确保预防这种病毒引起的疾病方面并非完全有效。事实上，针对EHV - 1相关疾病的疫苗接种实际效果尚未得到衡量，且关于该主题尚无系统综述。
对商业疫苗或候选疫苗在随机对照试验（RCT）中针对EHV - 1的疗效进行系统综述和荟萃分析，所有试验均涉及对受试对象进行实验性攻毒。
系统综述和荟萃分析。
在PubMed、科学引文索引扩展版、Scopus和CAB文摘数据库中使用搜索算法（（[马疱疹病毒或马属疱疹病毒或EHV - 1]） AND 疫苗*） AND （试验或实验或攻毒）搜索随机对照试验。在适当情况下，使用RevMan 5.4进行荟萃分析。
选取了八项研究，并对其各自的特征和可能存在的缺陷进行了分析。随机对照试验的结果显示，接种疫苗后EHV - 1感染的临床和病毒学结果总体有所改善，但效果非常轻微。在许多分析的病例中，由于研究报告的详细数据匮乏，无法对参数进行比较，这可能放大了有益效果降低的情况。
所选研究存在显著的异质性且报告质量较差。
荟萃分析表明，EHV - 1疫苗接种通常会使临床和病毒学结果略有改善，尽管程度不显著。累积结果可能受到研究中未系统报告的某些参数信息缺乏的影响。报告标准的提高和所收集数据更好的标准化可能会提高每项研究的质量，并使各项研究之间能够进行更有效的比较。
