"Unprecedented": Flu now widespread in 36 states

Flu season strikes as cases spike nationwide 03:25

The flu is getting a fast start on 2015. It is now widespread in 36 states, an earlier and wider spread than usual. At least 15 children have died so far. This week in Minnesota, a record number of lab specimens were sent in for testing.

Some hospitals in North Carolina and Michigan are now restricting visitors and volunteers under 18 from entering. Delaware is reporting nine times as many cases as this time last year. Another hard hit state is Georgia.

The state is fighting an epidemic of the H3N2 strain of influenza A. Scientists discovered the most common strain of the influenza had mutated soon after this year's flu vaccine was produced. The vaccine effictive only a third of the time against this year's influenza. Henry Dunbar got a flu shot, and still got the virus.

A strain of influenza has taken hold in 36 states, despite a vaccine given earlier in 2014. CBS News

His fever was 101 again today. His mother Colleen was worried. "I've read where if the fever persists more than a couple days, you should check to see whether you have the flu," she said, looking at her son's test. "That really dark line by the 'A' means it's Influenza A."

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The Centers for Disease Control says this flu season could be severe. Flu-related hospitalizations nationally are double what they were this time last year.

Holly McDonald, a family nurse practitioner, treated Henry. She also oversees all 48 CVS Minute Clinics in Georgia. She says she's seeing as many as 10 patients a day.

"There have certainly been some days when we see that many in a single clinic, which is unprecedented," she said.

McDonald has empathy for her flu patients. She's getting over the virus herself.

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"It was really bone-breaking pain," she said. "Back pain, especially. Headache, severe cough, sore throat and fever. It puts you down and it's hard to function."

Colleen Dunbar says her son has "permission to be a slug for a couple days." He's supposed to get plenty of rest -- and drink lots of fluids.

Forty percent of Americans have had a flu shot recently. But a vaccines designed early in the year is, in many ways, an educated guess about which flu strains will become threats.