Centre for International Health, Ludwig-Maximilian-University, Munich, Germany.
Kazakh National Medical University, Almaty, Kazakhstan.
Int J Infect Dis. 2019 Jan;78:121-127. doi: 10.1016/j.ijid.2018.10.015. Epub 2018 Oct 25.
The aim of this study was to detect the seroprevalence of Crimean-Congo haemorrhagic fever virus (CCHFV) in patients with fever of unknown origin (FUO) in endemic (Kyzylorda) and non-endemic (Almaty) oblasts of Kazakhstan.
Paired serum samples from 802 patients with FUO were collected. Serum samples were investigated by ELISA to detect IgG and IgM antibodies against CCHFV. Sera with suspected acute infection were further investigated by RT-PCR to detect the viral RNA.
IgG antibodies were detected in 12.7% of the sera from both oblasts. Acute infection was shown by IgM ELISA in four patients from Kyzylorda, with only one developing severe CCHF. Viral RNA was found by RT-PCR in the other three patients' sera. Phylogenetic analysis of partial L and S segments revealed CCHFV genotype Asia 2 and a possible reassortment between the genotypes Asia 1/Asia 2. Animal husbandry, such as working with cattle and horses, was significantly associated with CCHFV seropositivity.
The antibodies and viral RNA detected in sera indicate that mild or even asymptomatic CCHFV infections are presented in Kazakhstan. This study describes the circulation of CCHFV in the so far non-endemic Almaty oblast for the first time. In conclusion, physicians treating patients with FUO in Kazakhstan should be aware of mild CCHF.
本研究旨在检测哈萨克斯坦流行（克孜勒奥尔达）和非流行（阿拉木图）地区不明原因发热（FUO）患者中克里米亚-刚果出血热病毒（CCHFV）的血清流行率。
收集了 802 例 FUO 患者的配对血清样本。采用 ELISA 法检测血清中针对 CCHFV 的 IgG 和 IgM 抗体。对疑似急性感染的血清进行 RT-PCR 检测以检测病毒 RNA。
两个地区的血清中 IgG 抗体的检出率为 12.7%。克孜勒奥尔达的 4 例患者的 IgM ELISA 检测显示急性感染，只有 1 例发生严重的克里米亚-刚果出血热。另外 3 例患者的血清中通过 RT-PCR 发现了病毒 RNA。部分 L 和 S 片段的系统进化分析显示 CCHFV 基因型为亚洲 2 型，可能存在亚洲 1/亚洲 2 型的重组。畜牧业，如与牛和马一起工作，与 CCHFV 血清阳性显著相关。
血清中检测到的抗体和病毒 RNA 表明哈萨克斯坦存在轻度甚至无症状的 CCHFV 感染。本研究首次描述了 CCHFV 在迄今非流行的阿拉木图地区的传播。总之，在哈萨克斯坦治疗 FUO 患者的医生应该意识到轻度 CCHF 的存在。
