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Researchers work to improve effectiveness of flu shots
02:33 - Source: CNN
CNN  — 

The flu season is still in full swing and it’s likely to continue for several more weeks, and if you haven’t gotten a flu shot yet, you should, according to the US Centers for Disease Control and Prevention.

The vaccine doesn’t offer perfect protection – it never does – but a new CDC report says it has significantly reduced medical visits associated with influenza so far this season, and offers a substantial protective benefit.

We won’t know exactly how well-matched the flu vaccine is for the viruses circulating until the season is over, but the CDC published this interim report to get an early sense of how well the vaccine is working.

One of the ways the CDC does this is to look at how many people with an acute respiratory illness are sick enough to go to a doctor at five study sites around the United States. Researchers determines how many have flu and how many had a flu shot.

According to the report published Thursday, the vaccine reduced doctor visits associated with flu by 45%. For the influenza B/Victoria viruses it was 50% effective. It was only 37% effective against influenza A.

This is mostly in line with other seasons, according to the CDC. Typically, the flu shot has been 40% to 60% effective in interim estimates when the flu vaccine viruses match the viruses circulating.

The CDC says it considers this vaccine to be “substantial protection” for children ages 6 months to 17 years old, reducing doctor visits associated with the flu among children by 55%. That’s notable because this flu season has been particularly hard on children.

Ninety-two children have died from flu in the United States so far this season. Other than the 2009 influenza A (H1N1) pandemic, this is the largest number of deaths reported for this time of the season since reporting began for the 2004-2005 flu season, the report said.

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The report notes that the number of severe illnesses among children younger than 18 years old and young adults ages 18 to 49 are also higher at this time when compared to other recent seasons.

The report says this flu season had one of the earliest starts since 2009, and flu activity remains high in most regions of the United States.

The CDC recommends that as long as the virus is circulating, it’s not too late to get a vaccine.

If you do get the flu, the CDC recommends you ask your doctor for a prescription for antiviral medication, whether you got the shot or not. The key is to get the medication as soon as you start to feel sick – those drugs can shorten how long you are sick and curb some of the symptoms.