03-31-2021, 01:26 AM
The CDC did a study to see the effectiveness of vaccines that are being given throughout the county. Â They foundÂ
The clinical studies had shown about 95% effectiveness after 2 weeks after the second shot for detected COVID infection (but may have missed asymptomatic COVID).
The study ran from Dec. 14 to March 13, so the 3,950 subjects were exposed to the mixture of variants across that time. Â The subjects took their own nasal swabs weekly, which were tested via RT-PCR. Â Thus it could detect asymptomatic cases. Â 10% of the cases were asymptomatic, but 58% of cases were detected by RT-PCR before symptoms were noticed.
All subjects were essential workers, including health care personnel and first responders from six states: Arizona, Florida, Minnesota, Oregon, Texas and Utah. Â (I note that Florida had a number of variant cases, but I'm not sure about the other states.)
I believe this study can help pin down the percent of asymptomatic cases (at least in vaccinated subject) and may clarify how delayed after the infection takes hold before symptoms appear. Â Unfortunately, only the press release seems to be out at this time.
- 80% effectiveness after 2 weeks after the first shot for the Pfizer & Moderna vaccines
- 90% effectiveness after 2 weeks after the second shot for the Pfizer & Moderna vaccines
The clinical studies had shown about 95% effectiveness after 2 weeks after the second shot for detected COVID infection (but may have missed asymptomatic COVID).
The study ran from Dec. 14 to March 13, so the 3,950 subjects were exposed to the mixture of variants across that time. Â The subjects took their own nasal swabs weekly, which were tested via RT-PCR. Â Thus it could detect asymptomatic cases. Â 10% of the cases were asymptomatic, but 58% of cases were detected by RT-PCR before symptoms were noticed.
All subjects were essential workers, including health care personnel and first responders from six states: Arizona, Florida, Minnesota, Oregon, Texas and Utah. Â (I note that Florida had a number of variant cases, but I'm not sure about the other states.)
I believe this study can help pin down the percent of asymptomatic cases (at least in vaccinated subject) and may clarify how delayed after the infection takes hold before symptoms appear. Â Unfortunately, only the press release seems to be out at this time.