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Cold, Flu, & Cough Health Center

Flu Hits Unvaccinated Hardest, Study Finds

Those who have had vaccine are far less likely to need intensive-care unit
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Twenty-two of the patients required treatment in the ICU. Just two of those patients had been vaccinated against the flu, and they had other medical conditions that would prevent their bodies from effectively responding to the vaccine.

Of the 11 other vaccinated people who were hospitalized but not in intensive care, nine were immune-compromised in some way.

Wolfe said these findings show that even if the flu vaccine doesn't completely prevent you from getting the flu, it does offer "a protective effect against severe disease."

The researchers also found that about one-third of the flu cases admitted to intensive care had previously tested negative for the flu, suggesting that doctors shouldn't depend on flu tests alone when deciding whether to prescribe anti-viral medications.

Norbert Herzog, a professor in the department of medical sciences at the Frank H. Netter School of Medicine at Quinnipiac University in Hamden, Conn., said it's a shame that flu vaccination rates aren't higher. "Flu kills around 35,000 people a year, and about 200,000 a year end up in the hospital," he said.

Both experts said the flu vaccine is by far the best way to protect yourself against the flu.

"It's never too late to get vaccinated," Herzog said. "The flu circulates best in the colder months, but it can strike at any time. And people need to understand that just because they got the flu shot last year, doesn't mean they have immunity for this year. The strains change from year to year."

Other preventive steps include washing your hands or using hand sanitizer, and staying away from people who might have the flu.

If you're the one who's sick, stay home to prevent spreading the infection to others. Wolfe suggested keeping your hands out of your eyes, nose and mouth as well.

Wolfe also noted that 10 percent to 15 percent of people will notice some muscle soreness and feel a bit unwell for a few days after getting a flu shot.

"That's the protective effect of the vaccine you're feeling," he said. "Your immune system is recognizing a virus and responding."

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