中文摘要：

目的 对1989年8月分离自云南省盈江县蚊虫的2株登革病毒进行生物学及分子特征的鉴定，明确这两株病毒的血清型及基因型。方法 蚊虫用BHK21细胞和乳鼠法分离病毒，用间接免疫荧光试验、RT-PCR等方法进行鉴定，并对这两株病毒的分子生物学特征进行分析。结果 从自纹伊蚊和达勒姆阿蚊中各分离到一株病毒；分别命名为M110和M113，这两株病毒对BHK21细胞能产生明显的细胞病变。脑内接种乳鼠4d左右导致乳鼠死亡。该病毒经血凝、血凝抑制和间接免疫荧光试验提示为黄病毒。分别用黄病毒属特异引物、登革4型病毒NS1和NS2a基因片段特异引物进行RT—PCR扩增、序列测定，证实为登革4型病毒。NS1和NS2a基因序列片段分析表明，M110和M113的NS1核苷酸序列与登革4型病毒基因I型的H241株（Y19176）同源性最高。分别为99％、98％；NS2a基因片段与H241的核苷酸序列的同源性分别为96．5％、97．1％。结论 从盈江县蚊虫分离到的M110和M113病毒为登革4型病毒基因I型，表明云南省西部边境地区在20世纪80年代发生过登革4型病毒的流行。

英文摘要：

To identify the serum type and genotype of two dengue virus strains M110 and M113 from mosquitoes collected in 1989 in Yinjiang county, Yunnan province of China. BHK21 cell line and 3-day suckling mice were inoculated with two viruses and molecular biological characteristics of two viruses were identified by indirect immunofluorescent antibody and reverse transcription-polymerase chain reaction （RT-PCR） techniques. Strains M110 and M113 isolated from Aedes albopictus and Armigeres durhami, respectively, which were fatal to suckling mice at 4 days alter intracerebrally inoculation and had eytopathologic effects on BHK21 cells, showed a positive reaction to dengue antibody and could be amplified Ly using flavivirus primers and dengue type-4 NSl gene primers and dengue type-4 NS2a gene primers. The nucleotide sequences showed that compared with dengue type-4 virus gene type I （H241 strain,Y19176）, NSl sequences of M110 and M113 had a very high homology to H241 （99% and 98%） and the similar results with NS2a（96.5% and 97.1%）. The isolated 2 virus strains belonged to gene type I of dengue type-4 virus and such results showed that there existed epidemic probabilities of the disease in western border region el Yunnan province in last 1980＇ s.