从这段开始看
（这段+Ongoing那段）
Furthermore, both trials were largely conducted before the severe acute respir
atory syndrome coronavirus 2 (SARS-CoV-2) variant B.1.1.7 became dominant in t
he United Kingdom9.
以下提到一些疫苗对于B.1.1.7的防护力（文献15、16、18、19等）
其中16直接指出 BNT 非常推荐使用在英国变种上
所以这篇文献的下一段才提出对上面文献的质疑
However, existing studies have either investigated defined sub-populations9,18
,19 or have relied on the results from symptomatic testing programs15,17, pote
ntially leading to bias from vaccination status influencing the test-seeking b
ehavior of cases not requiring health care
他认为这些文献选用的都已经是有症状者或特定的子群体，所以会造成结果的偏差
基本上你选读的这篇“主要目的”是为AZ效力较差做翻案
没说他结论错，但这篇的存在也说明“在主流研究中”BNT效力确实较佳
至于两者真实效力如何
反正你选读了这篇
我以这样的内容回应你
基本上就注定我们的看法不同了
而我确实与这篇提到的部分文献看法一样
BNT比AZ更适合作为对变种的疫苗
就举本篇第16号参考文献内容
BNT162b2 vaccine to be 70% 21 days after the first dose, increasing to 85% 7 d
ays after the second dose in our study population. Given the dominance of the
B.1.1.7 variant in England during the study period, which accounted for 50% or
more positive tests in Pillar 2 laboratories since the beginning of December,
2020, in the South East, London, and East of England, and in all regions by e
arly January 2021 (with Yorkshire and the Humber the last region), our finding
s suggest that the BNT162b2 is effective against the B1.1.7.16
我再举第19篇，针对80岁以上老人的文献结论也是BNT较佳
BNT
From 14 days after the second dose a vaccination effectiveness of 89% (85% to
93%) was found compared with the increased baseline risk
AZ
With ChAdOx1-S, effects were seen from 14 to 20 days after vaccination, reachi
ng an effectiveness of 60% (41% to 73%) from 28 to 34 days, increasing to 73%(
27% to 90%) from day 35 onwards.
以上
为避免断章取义，我尽量引用原文。