新冠病毒演化出两个亚型

A Chinese doctor has warned the novel coronavirus can attack a person's central nervous system. It is the first case that proves the novel coronavirus can damage people's central nervous system, media reported Wednesday.
澎湃新闻3月4日报道，北京地坛医院首次报告了新冠病毒攻击中枢神经系统的病例。

Liu Jingyuan, dean of the ICU department of the Beijing Ditan Hospital and attending doctor of the 56-year-old patient, warned that doctors should check cerebrospinal fluid if patients suddenly slip in and out of consciousness, in order to lower the fatality rate of critical patients. The patient recovered and was discharged from hospital on February 25.
北京地坛医院ICU主任刘景院参与了这名56岁患者的救治，他表示一旦患者出现意识障碍，医生应及时进行脑脊液等相关检查，从而进一步降低危重病人的病死率。

The patient was hospitalized one month earlier for respiratory failure. Doctors conducted gene sequencing on his cerebrospinal fluid as he showed symptoms of neurological disorder like twitching on the face after days of treatments.
该患者于1月24日以新冠肺炎、危重型、呼吸衰竭收入院。治疗数日后，医生检查发现患者出现颌面及口角频繁抽搐等神经系统紊乱症状。

China issued the seventh treatment guide for COVID-19 on Tuesday that includes results of autopsies, which clarifies that the novel coronavirus could damage various organs including brain tissue.
3月3日，国家卫生健康委员会发布了《新型冠状病毒肺炎诊疗方案（试行第七版）》，其中指出新冠病毒可能会对包括脑组织在内的器官造成伤害。

The novel coronavirus has evolved into two major subtypes, a Chinese study has revealed.
日前，中国科学团队发现，新冠病毒演化出了两个亚型。

The study, titled On the origin and continuing evolution of SARS-CoV-2, was published on the National Science Review of the Chinese Academy of Sciences (CAS) on Tuesday (March 3).
3月3日，中国科学院主办的《国家科学评论》（National Science Review）发表题为《关于SARS-CoV-2的起源和持续进化》的论文。

By analyzing the genome-wide molecular evolution of 103 novel coronavirus samples, scientists found 101 samples that can be categorized into S-cov and L-cov based on 149 mutation spots on virus strains.
论文通过对目前为止最大规模的103个新冠病毒全基因组分子进化分析，发现病毒株已发生了149个突变点，而且多数是近期产生的。该研究揭示：新冠病毒已经演化出L和S两个亚型。其中101个属于这两个亚型。

The paper states that S type, accounting for 30 percent, is closer to the bat-related coronavirus and is relatively older, while the L type was more prevalent in the early stages of the outbreak in Wuhan.
基因组数据表明，感染S型的比例占30%，L型的感染比例占70%。S型与蝙蝠来源的冠状病毒在进化树上更接近，从而得出S型相对更古老的结论。L型在武汉爆发疫情的早期阶段更为普遍。

Human intervention may have placed more severe selective pressure on the L type, which might be more aggressive and spread more quickly than the S type.
人为干预可能对L亚型施加了更大的选择性压力，如果没有这些干预，L亚型可能更具侵略性和扩散得更快速。

However, the authors highlighted the fact the data examined in the study is very limited. How L type strains evolved from S type, as well as how these mutations would affect the transmission and pathogenesis of the virus, are still unknown.
不过，论文作者也指出研究数据很有限。L型如何从S型演化而来，以及变异如何影响病毒传播和发病机制，依然是未知数。

Scientists also found most patients caught either the L or S type of novel coronavirus strain. But there might be exceptions to the rule that should be followed with further research. For example, the study said a 63-year-old female patient in Chicago had likely contracted both L and S types of novel coronavirus strains when she traveled in Wuhan and returned to the United States on Jan 13.
样本显示，大部分患者只感染了L亚型或S亚型中的一个。但其中一位近期有过武汉旅行史的63岁美国患者却很有可能同时感染了L型和S型新冠病毒。不过，该论文作者表示目前还无法排除新突变型的可能性。