麻疹乙脑二联活疫苗的试制

应用麻疹沪191株制备的疫苗原液与乙脑SA14-14-2株制备的疫苗原液混合制成二联疫苗，经试验其病毒滴度与其同批单价苗差异无显著意义（P＞0．2），联合苗与相应的标准抗血清均有高度的特异性，免疫小鼠后以乙脑JEP3株强毒攻击的保护效价与其单价乙脑苗差异亦无显著意义（P＞0．5）。表明两株病毒无干扰现象。试制3批二联苗，经全面检定，结果完全符合现行规程要求。其中病毒滴度麻疹苗为4．5LogCCID50／ml，乙脑苗为6．11～6．18LogPFU／ml，安全试验表明，二联合苗的弱毒力特性稳定。

Experimental Preparation of Live Measles-Japanese Encephalitis Vaccine

A combined vaccine was prepared by mixing the stock solutions of measles (Hu 191 strain ) and Japanese encephalitis (SA14-14-2 strain ) vaccines. No significant difference was found among the titers of the combined vaccine and the same lots of monovalent measles or JE vaccines. Both the combined vaccine and corresponding antiserum showed good specificity. The mice immunized with the combined vacccine and monvalent JE vaccine were challenged with JE P3 strain. The result showed no significant difference between the protective titiers of the 2 vaccines (p>0. 5),and no interference between P3 and SA14-14-2strains. Three lots of the combined vaccine were prepared and completely detected. The results meet the Chinese requirements for Biological Products. The measle and JE virus titers of the combined vaccine were 4. 5LogCCID50/ml and 6. 11～6.18Log PFU/ml, respectively.Safety test showed that the virulence of the combined vaccine were weak and stable.