KAPLAN C
Bull World Health Organ. 1960;22(3-4):393-7.
The final test of a smallpox vaccine is its capacity to prevent the disease from developing in inoculated individuals. This capacity, however, cannot be measured directly, so that other methods of assessing the efficacy of vaccine have had to be developed. A laboratory method-pock counting on the chorio-allantoic membrane of chick embryos-has recently been shown to provide a reasonably reliable estimate of the number of infective units in a given vaccine. In this paper, the author compares this pock-counting method with another method-titration by intravenous injection of chick embryos. He concludes that, although the reproducibility of titrations by intravenous injection compares very favourably with that obtained by chorio-allantoic inoculation, the former method would not be advantageous for the assay of vaccines, since it is very time-consuming and since differences in virulence might obscure comparisons between the efficacy of vaccines.
天花疫苗的最终检验是其在接种个体中预防疾病发生的能力。然而，这种能力无法直接测量，因此必须开发其他评估疫苗效力的方法。一种实验室方法——在鸡胚绒毛尿囊膜上进行痘疱计数——最近已被证明能对给定疫苗中的感染单位数量提供相当可靠的估计。在本文中，作者将这种痘疱计数方法与另一种方法——通过静脉注射鸡胚进行滴定法——进行了比较。他得出结论，虽然静脉注射滴定法的可重复性与绒毛尿囊接种法相比非常有利，但前一种方法对疫苗检测并无优势，因为它非常耗时，而且毒力差异可能会模糊疫苗效力之间的比较。
