【摘要】 目的对2013-2016年广东的登革病毒血清I型序列进行分子流行病学分析,研究血清I型登革病毒在广东省的流行特征。方法分离获得2013-2016年登革病毒血清I型序列,建立全球登革病毒血清I最大似然树,预测第2簇病毒的进化速率、共祖位置;使用PAML软件计算选择压力。结果 2013-2016年的广东序列分别聚类在11簇分支中,其中8簇为基因I型毒株、1簇基因IV型毒株、2簇基因V型毒株,且与东南亚国家分离的序列聚类在一起。第2簇病毒表现出一定的独特性,最大置信树以及时空动态图显示这簇株系最早是由泰国传入广州,之后又在广东地区流行。第2簇病毒的相对进化速率要比文献报道的DENV-1基因I型的进化速率要大,但该簇病毒的序列不存在正选择压力。结论广东地区流行的登革病毒主要是从东南亚国家输入,同时发现一簇疑似本地化的株系,具有部分本地化的特征,包括:跨年传播、独立成簇,但还需要更多的证据去判定登革热是否已形成本地化。更多还原

【Abstract】 Objective To conduct a molecular epidemiological analysis of the dengue virus serum type 1 sequence in Guangdong from 2013 to 2016,and to study the epidemic characteristics of the serum type 1 dengue virus in Guangdong Province. Methods The dengue virus serum type 1 sequence was isolated from 2013 to 2016 to establish the global maximum likelihood tree of dengue virus serotype 1,predicting the evolution rate and the common ancestral location of cluster 2 virus.The selection pressure was calculated using the PAML software. Results The 2013-2016 Guangdong sequences were clustered in 11 clusters,of which 8 clusters were genotype I,1 cluster genotype IV,and 2 clusters of genotype V,and were isolated from Southeast Asian countries. The sequences were clustered together. The second cluster of viruses showed a certain degree of uniqueness. The maximum clade credibility tree and spatio-temporal dynamics showed that this strain was first introduced from Thailand to Guangzhou,and later became popular in Guangdong. The relative evolution rate of the second cluster of viruses was greater than the evolution rate of the genotype I of DENV-1 reported in the literature,but there was no positive selection pressure for the sequence of the cluster virus. Conclusion The dengue virus that is prevalent in Guangdong is imported from Southeast Asian countries. At the same time,a cluster of suspected localized strains has been found to have localized characteristics,including spread across the years,and independent clustering. However,more evidence is needed to determine if dengue has become localized.更多还原