Louisiana is a hotbed of flu activity. How effective is the flu vaccine?

NEW ORLEANS -- Louisiana and Mississippi are in the red, signaling a hotbed of flu activity here locally.

The Centers for Disease Control and Prevention recently issued a report noting that Louisiana in particular is suffering from a "widespread" threat.

"We should be alarmed every year. Every year 200,000 people are hospitalized on average. Somewhere between 20,000-35,000 may die from the flu in this country. That's alarming, no matter how you look at it, regardless of the year, particularly for a vaccine preventable illness," says Dr. Fred Lopez, with LSU Health Infectious Diseases.

But this year's flu vaccine is much less effective than in previous years, meaning those who are vaccinated against the flu may still get sick.

Lopez says the flu shot is only 10 percent effective. Typically, it's 40-60 percent effective. Why the difference this year? Lopez says there are several reasons.

One reason is because not everybody responds to the vaccine. Another reason is because strains can change over time, making the initial vaccine much less effective. That could be what's happening now.

"I think that the key preventative strategy, regardless of how effective that vaccine is going to be this year in the United States, is to get vaccinated," says Dr. Lopez.