目的  验证荧光灶试验（fluorescence focus assay，FFA）作为测定六价轮状病毒疫苗各型病毒滴度方法的可行性。方法  采用FFA法测定轮状病毒G1、G2、G3、G4、G8、G9型滴度，并验证该法的专属性、精密度、线性、准确性、范围和耐用性。 结果  各型病毒均可与对应的单克隆抗体（单抗）发生特异性荧光灶反应，不与抗异型病毒单抗发生交叉反应。试验内和试验间测定结果的相对标准偏差均小于5%。各型轮状病毒实测滴度与理论滴度间的线性相关系数均≥0.99。不同稀释度各型病毒的回收率为90%~120%。改变病毒培养时间对检测结果没有影响。该法的定量限为：G1、G2、G3、G4、G8、G9型滴度分别>2.8、>4.2 、>3.7、>3.6、>4.1和>4.2 lg荧光灶单位/ml，均符合六价轮状病毒疫苗的质控要求。结论  该法测定不同型轮状病毒滴度具有较好的专属性、精密度、线性和准确性，可用于六价轮状病毒疫苗各型病毒滴度的测定。

Objective   To validate the feasibility of fluorescence focus assay (FFA) as a method for detection of hexavalent rotavirus vaccine. Methods  The titers of rotavirus types G1, G2, G3, G4, G8, G9 were detected by FFA, and the specificity, precision, linearity, accuracy, range and robustness of FAA were validated. Results  The different types of rotavirus had specific fluorescence reaction with corresponding monoclonal antibody, and no cross reaction with anti-heterotypic virus antibody. The relative standard deviations of results in inner- and inter-assay were all <5%. The recovery rates of different concentrations of 6 types viruses were 90%-120%. The correlation coefficients between the measured and theoretical titers of the different types of rotavirus were all >0.99 . Changing virus incubation time made no significant difference in the detection results. The FFA detection limits of rotavirus types G1, G2, G3, G4, G8 and G9 titers were >2.8, >4.2, >3.7, >3.6, >4.1 and >4.2 lg fluorescence focus unit/ml, respectively, which met the quality control requirment of the hexavalent rotavirus vaccine. Conclusion  The FFA has good specificity, precision, linearity and accuracy, and can be applied to detection of hexavalent rotavirus vaccine.