evidence: Viral Pfizer 'admission' not what it seems A claim that a Pfizer spokeswoman "admitted" that the company's COVID-19 vaccine was "never tested on preventing transmission" is not quite right, CheckMate has found. In a video viewed close to 13 million times on Twitter alone, Rob Roos, a Dutch member of the European Parliament, alleges that a Pfizer director "admitted" that "at the time of introduction, the vaccine had never been tested on stopping the transmission of the virus".