Common carp (Cyprinus carpio) is a very important fish species for warm-water aquaculture in Croatia. All Croatian carp farms are subjected to a surveillance programme for the presence of koi herpesvirus (KHV), causing a deadly disease called koi herpesvirus disease (KHVD). However, there is no surveillance for other viral pathogens of importance like carp edema virus (CEV), a causative agent of koi sleepy disease (KSD). During regular testing within the KHVD surveillance programme, we tested samples for CEV simultaneously. The screening indicated possible outbreaks of KHVD and KSD. During 2016, KHVD broke out in an isolated area and soon thereafter a KHV eradication programme was successfully performed. However, during 2018 and 2019, two additional mortality events occurred in lakes in the southern part of Croatia during the spring. Samples from both events tested positive for CEV. An epidemiological investigation confirmed the introduction of infected carps from an infected farm to one of the lakes. To prevent the spreading of CEV into open waters, it is of utmost importance to introduce CEV testing before fish movement or to perform regular testing of all carp farms in the country to determine CEV prevalence for the purpose of implementation of control measures.

中文翻译：

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锦鲤疱疹病毒和鲤鱼水肿病毒威胁克罗地亚的鲤鱼养殖。

鲤鱼（Cyprinus carpio）是克罗地亚温水养殖中非常重要的鱼类。所有克罗地亚鲤鱼养殖场都接受了有关锦鲤疱疹病毒（KHV）存在的监视程序，导致致命疾病，称为锦鲤疱疹病毒病（KHVD）。但是，没有监视其他重要的病毒病原体，例如鲤鱼浮肿病毒（CEV），这是锦鲤嗜睡病（KSD）的病原体。在KHVD监视计划内的常规测试中，我们同时测试了CEV样品。筛查表明可能爆发了KHVD和KSD。2016年，KHVD在一个偏远地区爆发，此后不久便成功实施了KHV根除计划。但是，在2018年和2019年春季期间，克罗地亚南部的湖泊又发生了两次死亡事件。来自这两个事件的样本的CEV均呈阳性。一项流行病学调查证实，受感染的鲤鱼是从受感染的农场引入一个湖泊中的。为了防止CEV扩散到开阔水域中，至关重要的是在鱼类移徙之前进行CEV测试，或者对该国所有鲤鱼养殖场进行定期测试，以确定CEV的发生率，以实施控制措施。