Abdelgawad Azza, Damiani Armando, Ho Simon Y W, Strauss Günter, Szentiks Claudia A, East Marion L, Osterrieder Nikolaus, Greenwood Alex D
Leibniz-Institute for Zoo and Wildlife Research, Alfred-Kowalke-Strasse 17, Berlin 10315, Germany.
Institut für Virologie, Freie Universität Berlin, Robert-von-Ostertag-Str. 7-13, Berlin 14163, Germany.
Viruses. 2016 Sep 20;8(9):262. doi: 10.3390/v8090262.
Alphaherpesviruses are highly prevalent in equine populations and co-infections with more than one of these viruses' strains frequently diagnosed. Lytic replication and latency with subsequent reactivation, along with new episodes of disease, can be influenced by genetic diversity generated by spontaneous mutation and recombination. Latency enhances virus survival by providing an epidemiological strategy for long-term maintenance of divergent strains in animal populations. The alphaherpesviruses equine herpesvirus 1 (EHV-1) and 9 (EHV-9) have recently been shown to cross species barriers, including a recombinant EHV-1 observed in fatal infections of a polar bear and Asian rhinoceros. Little is known about the latency and genetic diversity of EHV-1 and EHV-9, especially among zoo and wild equids. Here, we report evidence of limited genetic diversity in EHV-9 in zebras, whereas there is substantial genetic variability in EHV-1. We demonstrate that zebras can be lytically and latently infected with both viruses concurrently. Such a co-occurrence of infection in zebras suggests that even relatively slow-evolving viruses such as equine herpesviruses have the potential to diversify rapidly by recombination. This has potential consequences for the diagnosis of these viruses and their management in wild and captive equid populations.
α疱疹病毒在马群中高度流行，经常诊断出感染不止一种这些病毒的毒株。裂解复制和潜伏以及随后的再激活，连同新的疾病发作，可能会受到自发突变和重组产生的遗传多样性的影响。潜伏通过为动物群体中不同毒株的长期维持提供一种流行病学策略来提高病毒的存活率。α疱疹病毒马疱疹病毒1型（EHV-1）和9型（EHV-9）最近已被证明能跨越物种屏障，包括在一只北极熊和亚洲犀牛的致命感染中观察到的重组EHV-1。关于EHV-1和EHV-9的潜伏和遗传多样性，尤其是在动物园和野生马科动物中，人们知之甚少。在此，我们报告了斑马中EHV-9遗传多样性有限的证据，而EHV-1存在大量遗传变异。我们证明斑马可以同时被这两种病毒进行裂解性感染和潜伏感染。斑马中这种感染的同时发生表明，即使是像马疱疹病毒这样进化相对缓慢的病毒也有可能通过重组迅速多样化。这对这些病毒的诊断及其在野生和圈养马科动物群体中的管理具有潜在影响。
