(HealthDay)—Flu needn't spoil the start of the new year, say U.S. health officials who urge children and adults to get vaccinated.
"Most of the flu season is still ahead of us, so it's not too late to get vaccinated," said Dr. Joseph Bresee of the U.S. Centers for Disease Control and Prevention.
But, get the shot soon because it can take several weeks to produce enough antibodies to give you maximum protection, the agency notes.
"We often see spikes in flu during and right after the holidays as people congregate and travel in planes that bring people close together," said Bresee, who is chief of epidemiology and prevention in the CDC's influenza division.
Flu activity will increase in most parts of the country over the next several weeks, before peaking in the next few months, he said.
The hardest-hit areas so far are New York, New Jersey, Puerto Rico, the Southeast and the Northwest, Bresee said.
Besides rolling up your sleeve for the flu injection, Bresee recommends taking simple precautions to prevent spreading the virus.
"Wash your hands, cover your cough and stay away from other people when you're sick," he said.
If you do get the flu, antiviral drugs, such as Tamiflu and Relenza, can help if taken early. That's particularly important for high-risk individuals, such as the elderly and people with chronic conditions, such as heart and lung disease, the CDC says.
These vulnerable people should "talk to their doctor about taking medicine that might prevent them from getting severely ill," Bresee said.
How effective a vaccine is depends on how good a match it is to the strains of flu virus circulating that year. Most years, the vaccine is between 40 percent and 60 percent effective, according to the CDC.
"The viruses we are seeing are very much like the strains in the vaccine, which is good news, because it means the vaccine should work better [than last year's vaccine]," Bresee said.
The vaccine supply is also good this year, with more than 131 million doses available, the agency said.
The predominant viral strain is influenza H3N2, Bresee said. But influenza H1N1 and influenza B viruses are also around, he said.
As of Dec. 9, only 40 percent of Americans had been vaccinated—nearly 2 percent fewer than at the same time last year, the CDC reported.
The falloff in vaccinations is most evident among people 50 and older. That's unfortunate, Bresee said, because last year flu was particularly hard on older people.
Flu activity can be unpredictable. Last year, the H3N2 virus started out as the dominant strain, only to be displaced by H1N1 as flu season hit full swing, he said.
In a typical flu season, flu complications—including pneumonia—send more than 200,000 Americans to the hospital. Death rates linked to flu vary annually, but have gone as high as 49,000 in a year, the CDC says.
Although hospitalizations for flu are still low, the highest rate is among the elderly.
The CDC recommends that anyone 6 months of age and older get a flu shot.
Besides the elderly and the chronically ill, pregnant women also fall into the high-risk group in need of vaccination, Brammer said.
Also, mothers of newborns need a flu shot to help protect their infants, who can't be vaccinated until they're 6 months old.
One recent change in guidelines is that the CDC's Advisory Committee on Immunization Practices does not recommend using the nasal spray vaccine, because it seems less effective than a shot.
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For more about flu, visit the U.S. Centers for Disease Control and Prevention.