The first discovery of the group IV GETV from Pangolin, China

We confirmed novel Group IV Getah virus (GETV) was detected from pangolin, which is the first discovered new host. And this is the first discovery of Group IV GETV in Guangxi province, China. This strain, named CHIKV-China/GX2020, is highly homologous to the 2017 Thailand strain. Bayesian analysis shows that GETV has a faster evolutionary rate with 3.487 (2.213–4.771) × 10⁻⁴ substitutions/site/year. The Lollipop plot demonstrated in detail the amino acid differences between the isolated strain and the other sequences of GETV of Group IV and revealed that more mutations occur in the structural protein E2. Compared with the 2017 Thailand isolate, GETV-China/GX2020 has been discovered important amino acid mutation of E2-H207N. This mutation results in a change in the conformation of the E2 protein, which may in turn affect the infectivity or pathogenicity of the virus. Existing surveillance programs and diagnostics efficiency of potential outbreaks of GETV need strengthen.

本研究证实从穿山甲中检出新型第四组盖塔病毒（Getah virus, GETV），穿山甲为该病毒首次发现的天然新宿主。这也是中国广西地区首次发现第四组盖塔病毒。该毒株命名为CHIKV-China/GX2020，与2017年泰国分离毒株的同源性极高。贝叶斯分析结果显示，盖塔病毒的进化速率较快，为3.487（2.213~4.771）×10^-4 替换位点/年。棒棒糖图（Lollipop plot）详细展示了本次分离毒株与其他第四组盖塔病毒序列之间的氨基酸差异，结果表明结构蛋白E2区域存在更多突变位点。与2017年泰国分离株相比，GETV-China/GX2020存在E2-H207N这一关键氨基酸突变。该突变可导致E2蛋白的构象发生改变，进而可能影响病毒的感染性或致病性。当前针对盖塔病毒潜在暴发的监测方案与诊断效率亟待加强。