一项新的研究表明，引起西非地区正在爆发的埃博拉疫情的病毒没有早先报告所提出的那样快速地突变。

这可帮助缓解人们的恐惧，因为较快的突变速度会赋予病毒新的特性，而后者又可帮助病毒更有效地传播并对目前的治疗产生抵抗性。

    2013年在西非开始的埃博拉疫情爆发是历史记载中规模最大、持续时间最长的埃博拉疫情，而对该病毒的测序只发表过几次。而基于这些有限测序数据所做的分析提示，该病毒突变的速度比先前观察的要快两倍。为了进一步表征该病毒的突变速度，T. Hoenen和同事从两个分别于不同的时间进入西非国家马里的埃博拉感染集群中取得了样本，并对其进行了测序。研究人员将此次的测序数据结果与之前分析过的测序数据相比较，这整个过程跨越了9个月的时间，研究结果表明该病毒的突变速度与过去在中部非洲埃博拉疫情爆发时所做的估计是一致的。

    研究人员的发现与此次爆发早期所得的测序数据分析相左;这意味着目前的诊断方法、疫苗和其它的治疗干预对该病毒应该仍然有效。

    原文链接：Mutation rate and genotype variation of Ebola virus from Mali casesequences

The occurrence of Ebola virus (EBOV) in West Africa during 2013–2015 is unprecedented. Early reports suggested that in this outbreak EBOV is mutating twice as fast as previously observed, which indicates the potential for changes in transmissibility and virulence and could render current molecular diagnostics andcountermeasures ineffective. We have determined additional full-length sequences from two clusters ofimported EBOV infections into Mali, and we show that the nucleotide substitution rate (9.6 × 10–4 substitutions per site per year) is consistent with rates observed in Central African outbreaks. In addition, overall variationamong all genotypes observed remains low. Thus, our data indicate that EBOV is not undergoing rapid evolution in humans during the current outbreak. This finding has important implications for outbreak response and public health decisions and should alleviate several previously raised concerns.