可能2针3针的都有，疫苗组的definition是 those with a record of completion of an Ad26.COV2.S, mRNA-1273 or BNT162b2 vaccination before the date of their first positive SARS-CoV-2 test (n = 34,863). Completion of vaccination was defined following CDC guidelines at the 14th day after the second shot of the mRNA-1273 or BNT162b2 vaccination series or the 14th day after the first shot of the Ad26.COV2.S vaccination.
要打两针，三针，还是四针呢？
可能2针3针的都有，疫苗组的definition是 those with a record of completion of an Ad26.COV2.S, mRNA-1273 or BNT162b2 vaccination before the date of their first positive SARS-CoV-2 test (n = 34,863). Completion of vaccination was defined following CDC guidelines at the 14th day after the second shot of the mRNA-1273 or BNT162b2 vaccination series or the 14th day after the first shot of the Ad26.COV2.S vaccination.