WATCH: Rudy Giuliani inadvertently reveals on Fox News that he doesn’t understand why COVID-19 is different than obesity

Rudy Giuliani made comments on Thursday that suggest he has absolutely no understanding how different diseases affect the human body.

The former New York City mayor was asked about his successor, former Mayor Michael Bloomberg, leading the tri-state effort to test and track the spread of coronavirus.

"That's totally ridiculous," Giuliani told Laura Ingraham.

"Then we should trace everyone for cancer," Giuliani argued, despite the fact that unlike coronavirus, cancer is a non-communicable disease.

"Yeah, army of tracers," Ingraham replied.

"We should trace everybody for cancer and heart disease and obesity," Giuliani said, naming three health threats that are not communicable.

"I mean, a lot of things kill you more than COVID-19," Giuliani argued. "So we should be traced for all those things."