Because people have little or no immunity to such a new subtype, their appearance tends to coincide with a very severe flu epidemic or pandemic.

The area was affected by a severe flu epidemic in 1918.

In the 1950 divisional playoffs, he was unable to practice due to a severe flu he had endured.

Low levels of selenium have been linked to increased risk of developing more severe flu.

Andrea has since developed a sickness (presumably a severe flu) and believes herself to be dying.

Rash entered Los Angeles Midway Hospital on Tuesday with what appeared to be severe flu.

But immobilized by a severe flu, he never left his hotel room.

Well, Jordan was not that old, recovering from a severe flu to make fall-away jumpers and win the most valuable player award for the third time.

Its symptoms resemble a severe flu, with fever, as well as poor muscle control or mental disorientation.

But it is too early to know just how severe the flu will be this winter.