People are worried about their parents, their chilren, and themselves.
Now, other members of the family could be in danger of getting the H1N1 virus.
This week it was confirmed a 13-year old cat right here in Iowa developed the flu virus after its owners came down with H1N1.
The feline was treated at Iowa State University and made a full recovery.
For a long time, it was thought that cats and dogs could not catch the virus from their owners.
After this case, that all changes.
Vets now say if you're sick, treat pets the same way you'd treat other people.
"If they're sick, showing symptoms of this flu - H1N1 - that we better keep our distance from our pets a little bit during this time as well," says Dr. Brad Petersen of Petersen Pet Hospital.
"You know, if your kitty does act sick, and doesn't want to eat, and it's just laying around and not being it's usual self, then maybe you oughtta call your vet," says Dr. Karen Taylor of Edgewood Animal Hospital.
While this is the first reported case of a cat getting H1N1, it's not the first animal.
Pigs, turkeys, even ferrets have all contracted the virus from humans.
In fact, one infected ferret in Nebraska eventually died.
H1N1 Cat Concerns Pet Owners