Jay Leno Jay Leno

Jay Leno's illness was serious enough to cancel two shows last week, but the late-night host made light of it during his monologue when he returned to the air Monday night.

Ever topical, Leno linked his illness to the swine flu. "What happened was — and I think was a mistake — I ate a raw pig a friend brought back from Mexico. ... It was delicious," Leno joked.

He went on to explain that he actually drove to his Burbank studio in his vintage Model T car on a cold morning last Thursday and didn't wear a jacket. "You know, I had this 103 degree fever. I was freezing and I got chills, and here at NBC we have an 'ODN,' overly dramatic nurse," Leno said.

He then went to the hospital, forcing NBC to cancel The Tonight Show and air two reruns, the first time the network had to so because of a Leno illness since he took the gig in 1992. Leno didn't specify his illness, but said doctors found no serious ailment.

Leno then turned back to comedy, poking fun at his Tonight Show successor, Conan O'Brien. "I had a horrible dream that I couldn't breathe. I felt like I was suffocating ... then I woke up and realized Conan was holding a pillow over my face," Leno said.

The comedian thanked fans for their well wishes, calls and cards. He also announced his "comedy stimulus tour" will continue with a free Mother's Day concert in Wilmington, Ohio.