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...

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.

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.

A lot of people were extremely confused during the pandemic and that's why they couldn't differentiate between actual verifiable information being shared and some random newscaster saying, wrongly, that vaccines prevented infection. A few years later they don't even know what is true anymore.

> The 95% they're claiming came straight from the press release which was only about sickness, not infection.

Yep, I repeated this so many times that toward the end I started just insulting people for not knowing.