
...two or three days later he gets the FLU
or a heart attack and he keels over.
Breaking Bad Season 3, Episode 12

Like you've got the FLU?
Breaking Bad Season 5, Episode 16

Flu. Boom.
Knocked me
on my ass for days.
Breaking Bad Season 2, Episode 10

Or the FLU, maybe.
Breaking Bad Season 2, Episode 1

For me, it was the FLU.
Breaking Bad Season 2, Episode 10