Fauci: Paul doesn't know what he's talking about 'and I want to say that officially'

Sen. Rand Paul (R-Ky.) on Tuesday escalated his ongoing feud with the nation's top infectious diseases doctor Anthony Fauci about the role the National Institutes of Health (NIH) played in funding controversial research in Wuhan, China.

The two traded barbs during a tense exchange, triggering a shouting match in which Fauci accused Paul of lying in order to further his agenda. 

During a Senate Health Committee hearing about the federal COVID-19 response, Paul said the NIH funded illegal gain-of-function research at the Wuhan Institute of Virology, which created a highly dangerous and transmissible virus able to infect humans. Gain-of-function is a controversial method where researchers make a pathogen more infectious, often to develop more effective treatments and vaccines.