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DocSavage | 2 years ago

Of course it was tested for preventing infection. It was tested for that as well as efficacy against severe disease: "Efficacy against laboratory-confirmed COVID-19 (with an onset of >= 7 days after receipt of the second dose) and against severe COVID-19.. was assessed among the participants 12 years of age or older." https://www.nejm.org/doi/10.1056/NEJMoa2110345

You seem to be conflating the vaccine having efficacy against infection and whether a vaccinated individual who still catches COVID-19 (since protection against infection is obviously not 100%) can transmit it. The efficacy against original COVID-19 strain infection was high (91.3% for the Pfizer vaccine).

Your first link speaks to the situation of a breakthrough infection being further transmitted. Since it wasn't clear HOW MUCH it curbed infection (under non-ideal/trial conditions), quarantines and caution were reasonable.

Here's a chart that showed the original test results across a number of vaccines. The efficacy vs infection dropped quite a bit with variants though the efficacy vs severe disease holds up better:

https://jbiomedsci.biomedcentral.com/articles/10.1186/s12929...

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Izkata|2 years ago

Do you know why it's "laboratory-confirmed"? Because they didn't test anyone until after symptoms showed.

Your confusion here is exactly what I'm talking about. The press release didn't conflate SARS-CoV-2 (the virus) with COVID-19 (the disease, as defined by a combination of symptoms and the virus). The line you quoted is measuring people who got sick, filtering out those who got sick due to a different virus, it's not measuring people who were infected. They didn't test all participants, so they couldn't make any claims against infection.

Edit:

> and whether a vaccinated individual who still catches COVID-19 (since protection against infection is obviously not 100%) can transmit it.

Getting infected does not mean you caught COVID-19, it means you were infected with SARS-CoV-2. You didn't get COVID-19 if you didn't get sick. Treating the two terms as the same thing is a media conflation people have just accepted, and an annoyance I have to explain every time this comes up because Pfizer was using the correct definitions in that press release.

DocSavage|2 years ago

Yes, you are correct that I should’ve said symptomatic infection (or COVID-19) because they were only trying to power the study for what they needed to clear EUA and not measuring ability to block transmission. The second paper I linked made the same mistake in its table header.