We thank Yi Huang and colleagues for their interest in our systematic review and meta-analysis on the immunogenicity, effectiveness, and safety of measles vaccination in infants younger than 9 months. In response to their letter, we can confirm that the same data on the risk of measles in unvaccinated children were used to estimate the vaccine effectiveness for the first dose of measles-containing vaccine (MCV1) administered to infants younger than 9 months and the vaccine effectiveness of MCV1 administered to infants aged 9 months and older. As in table 1, in addition to the Murray and Rasmussen estimate, this method was also used for all but one of the studies.

中文翻译：

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9个月以下婴儿的麻疹疫苗接种。

我们感谢Yi Huang及其同事对我们对9个月以下婴儿的麻疹疫苗接种的免疫原性，有效性和安全性进行系统综述和荟萃分析的兴趣。在他们的来信中，我们可以确认，未接种疫苗的儿童中的麻疹风险的相同数据已用于评估针对9个月以下婴儿和疫苗接种的第一剂含麻疹疫苗（MCV1）的疫苗有效性9个月以上婴儿MCV1的有效性。如表1所示，除了一项Murray和Rasmussen估计之外，该方法还用于除一项研究以外的所有研究。