All the flu activity has led some to question whether this year's flu shot is working. While health officials are still analyzing the vaccine, early indications are that it's about 60 percent effective, which is in line with what's been seen in other years.
The vaccine is reformulated each year, based on experts' best guess of which strains of the virus will predominate. This year's vaccine is well-matched to what's going around. The government estimates that between a third and half of Americans have gotten the vaccine.
In New York City, 57-year-old Judith Quinones skipped getting a flu shot this season and suffered her worst case of flu-like illness in years. She was laid up for nearly a month with fever and body aches. "I just couldn't function," she said.
But her daughter got the vaccine. "And she got sick twice," Quinones said.
Europe is also suffering an early flu season, though a milder strain predominates there. Flu reports are up, too, in China, Japan, the West Bank, the Gaza Strip, Algeria and the Republic of Congo. Britain has seen a surge in cases of norovirus.
On average, about 24,000 Americans die each flu season, according to the CDC. That's an estimate — the agency does not keep a running tally of adult flu deaths each year, only for children. Some state health departments do keep count, and they've reported dozens of flu deaths so far.
Flu usually peaks in midwinter. Symptoms can include fever, cough, runny nose, head and body aches and fatigue. Some people also suffer vomiting and diarrhea, and some develop pneumonia or other severe complications.
Most people with flu have a mild illness and can help themselves and protect others by staying home and resting. But people with severe symptoms should see a doctor. They may be given antiviral drugs or other medications to ease symptoms.
Flu vaccinations are recommended for everyone 6 months or older. Of the 20 children killed by the flu this season, only two were fully vaccinated.
AP Medical Writer Maria Cheng in London contributed to this report.
CDC flu: http://www.cdc.gov/flu/index.htm
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