COVID-19 vaccine breakthrough infections reported to CDC As of April 13, 2021, more than 75 million people in the United States had been fully vaccinated against COVID-19 since December 14, 2020. During the same time, CDC received 5,814 reports of vaccine breakthrough infections from 43 U.S. states and territories. Vaccine breakthrough infections were reported among people of all ages eligible for vaccination. 2,622 (45%) of the reported infections were among people ≥60 years of age. 3,752 (65%) of the people experiencing a breakthrough infection were female.1,695 (29%) of the vaccine breakthrough infections were reported as asymptomatic. 396 (7%) people with breakthrough infections were known to be hospitalized and 74 (1%) died. Of the 396 hospitalized patients, 133 (34%) were reported as asymptomatic or hospitalized for a reason not related to COVID-19. Of the 74 fatal cases, 9 (12%) were reported as asymptomatic or the patient died due to a cause not related to COVID-19. Hospitalizations and deaths that are not a direct result of COVID-19 are still considered vaccine breakthrough cases if the person was fully vaccinated and subsequently tested positive for COVID-19.
感染率一定要与暴露时间段联系起来，时间越长感染率越高。我们可以做一些假设：
【CDC 报道原文】https://www.cdc.gov/vaccines/covid-19/health-departments/
breakthrough-cases.html
1. 假设CDC说的75,000,000 fully vaccinated people，经历了30天（假定！）时间，有5,814人感染了新冠
2. 同一期间，美国每天大约60,000人感染新冠，也就是30天大约1,800,000人感染
我们来算一下比例：
疫苗组：感染率 = 5,814/75,000,000 ~= 0.00775%
全美国：假定总人口数328,200,000，感染率 = 1,800,000/328,200,000 ~= 5.48446%
估计保护率为：100% - 疫苗组感染率 / 全国组感染率 = 100% - 0.00775% / 5.48446% = 99.9%
注意除了时间段（30天）的假定我没把握，全国组感染率计算应该是比较保守的，因为许多从前得了新冠的应该排除在外。
如果把时间段缩短到7天（一周），那么全国组感染率是 420,000/328,200,000 ~= 0.
12797%，保护率计算出来是
100% - 疫苗组感染率 / 全国组感染率 = 100% - 0.12797% / 5.48446% = 93.9%
大家可以放入不同时间段看看保护率估计有何不同
雅力士的估算也是 99.99%
1,800,000/328,200,000 ~= 5.48446%？算术虽然不是体育老师教的，但也差了一个数
量级了。感染率纠正之后保护率应该是98.5%左右 不是99.9%
【 在 poyang (每天爱你多一些) 的大作中提到: 】
: 感染率一定要与暴露时间段联系起来，时间越长感染率越高。我们可以做一些假设：: breakthrough-cases.html
: 1. 假设CDC说的75,000,000 fully vaccinated people，经历了30天（假定！）时间，
: 有5,814人感染了新冠
: 2. 同一期间，美国每天大约60,000人感染新冠，也就是30天大约1,800,000人感染
: 我们来算一下比例：
: 疫苗组：感染率 = 5,814/75,000,000 ~= 0.00775%
: 全美国：假定总人口数328,200,000，感染率 = 1,800,000/328,200,000 ~= 5.48446%
: 估计保护率为：100% - 疫苗组感染率 / 全国组感染率 = 100% - 0.00775% / 5.
48446
: % = 99.9%
: ...................
这个计算有根本上的大缺点
打疫苗的人暴露时间并不是30天或7天
要看清楚这点，只要设想75M人都在最后一天打。0感染！
大趋势是：每日疫苗数量在加快，而非基本恒定。四分之一以上疫苗人是最近20天内打的。
因此“疫苗组”的感染率极可能被低估了很多
COVID-19 vaccine breakthrough infections reported to CDC
As of April 13, 2021, more than 75 million people in the United States had
been fully vaccinated against COVID-19 since December 14, 2020.
During the same time, CDC received 5,814 reports of vaccine breakthrough
infections from 43 U.S. states and territories.
Vaccine breakthrough infections were reported among people of all ages
eligible for vaccination.
2,622 (45%) of the reported infections were among people ≥60 years of age.
3,752 (65%) of the people experiencing a breakthrough infection were female.1,695 (29%) of the vaccine breakthrough infections were reported as
asymptomatic.
396 (7%) people with breakthrough infections were known to be hospitalized
and 74 (1%) died.
Of the 396 hospitalized patients, 133 (34%) were reported as asymptomatic or hospitalized for a reason not related to COVID-19.
Of the 74 fatal cases, 9 (12%) were reported as asymptomatic or the patient died due to a cause not related to COVID-19.
Hospitalizations and deaths that are not a direct result of COVID-19 are
still considered vaccine breakthrough cases if the person was fully
vaccinated and subsequently tested positive for COVID-19.
接种后感染的人数应该在 1 到 2 million 之间。没有测到的原因是病毒变异了，旧的技术测不出来