Laboratory of Arboviruses and Viral Haemorrhagic Fevers, Pasteur Institute of Iran, Tehran, Iran.
Epidemiol Infect. 2012 Aug;140(8):1525-9. doi: 10.1017/S0950268811002056. Epub 2011 Oct 19.
West Nile virus (WNV) is a mosquito-borne flavivirus which circulates in birds, horses and humans. An estimated 80% of WNV infections are asymptomatic. Fewer than 1% of infected persons develop neuroinvasive disease, which typically presents as encephalitis, meningitis, or acute flaccid paralysis. This study was conducted from January 2008 to June 2009 in Isfahan, Iran. Patients attending the emergency department with fever and loss of consciousness were consecutively included. Cerebrospinal fluids (CSF) were initially analysed through bacteriology and biochemistry examinations, resulting in those with evidence of meningitis being excluded. Patients' CSF and serum were diagnosed by serological and molecular assays. A total of 632 patients with fever and loss of consciousness were tested by CSF analyses. Samples of the remaining patients (39·4%) were referred for WNV investigation. Three (1·2%) of the patients were positive for both serum and CSF by RT-PCR, and six (2·4%) were positive only for IgG antibodies. History of insect bite, and blood transfusion and transplantation were risk factors for being positive by RT-PCR (P=0·048) and being IgG positive (P=0·024), respectively. The results of this study showed that the prevalence of West Nile fever is low in patients with encephalitis.
西尼罗河病毒（WNV）是一种通过蚊子传播的黄病毒，在鸟类、马和人类中循环。估计有 80%的 WNV 感染是无症状的。不到 1%的感染者会出现神经侵袭性疾病，通常表现为脑炎、脑膜炎或急性弛缓性麻痹。本研究于 2008 年 1 月至 2009 年 6 月在伊朗伊斯法罕进行。连续纳入急诊科就诊发热伴意识丧失的患者。最初通过细菌学和生物化学检查分析脑脊液，排除有证据表明患有脑膜炎的患者。通过血清学和分子检测对患者的脑脊液和血清进行诊断。共对 632 例发热伴意识丧失的患者进行了脑脊液分析检测。对其余患者（39.4%）的样本进行了 WNV 调查。通过 RT-PCR，有 3 名（1.2%）患者的血清和脑脊液均呈阳性，6 名（2.4%）患者仅 IgG 抗体呈阳性。蚊虫叮咬史、输血和移植是 RT-PCR 阳性（P=0.048）和 IgG 阳性（P=0.024）的危险因素。本研究结果表明，脑炎患者中西尼罗河热的患病率较低。
