(HealthDay)—The 2013 flu season is living up to its advance billing as one of the worst in years.
In Boston, where four flu-related deaths have been reported, Mayor Thomas Menino declared a state of emergency on Wednesday, and officials are working to set up free flu-vaccine initiatives. The city has already recorded 700 confirmed cases of flu, compared to 70 cases for all of last year, according to Boston.com.
At Lehigh Valley Hospital in Salisbury Township, Pa., a tent has been set up outside the emergency department because the medical center is struggling with a burgeoning number of flu cases, lehighvalleylive.com reported.
And in Chicago, Northwestern Memorial Hospital has recorded a 20 percent increase in flu patients every day, ABC News reported.
The 2012-2013 flu season got off to an early start, and it's only getting worse as peak flu season nears.
"As we moved into the end of December and January, activity has really picked up in a lot more states," Tom Skinner, a spokesman for the U.S. Centers for Disease Control and Prevention, told HealthDay.
According to the latest CDC statistics, which run through Dec. 29, a total of 41 states were reporting widespread flu activity. There have been 18 flu-related deaths of children so far.
The predominant strain so far this year is H3N2, Skinner said. "In years past when we have seen an H3N2 dominate, we tend to see more severe illness in young kids and the elderly," he added.
Flu season usually peaks in late January or early February, Skinner said, but by November the flu was already severe and widespread in some parts of the South and Southeast.
An estimated 36,000 people die from the flu and its complications in a typical season, according to the CDC. From 1976 to 2006, estimates of flu-associated deaths in the United States ranged from a low of about 3,000 to a high of about 49,000 people.
Dr. Robert Glatter, an emergency medicine physician at Lenox Hill Hospital in New York City, said: "We have been seeing an uptick in flu-related symptoms and influenza in the past two weeks—mainly since the end of Christmas. The patients with confirmed flu are older and have more severe illness compared to last flu season. However, we are also seeing an increase in children presenting with flu-like symptoms as well."
Experts say each flu season is unique. "Why one year flu season gets off to an early start versus a late start is unknown," Skinner said.
The best protection is for everyone 6 months of age and older to get the flu vaccine.
"It's not too late to get vaccinated," Skinner said. Ample vaccine was made available, but since it's late in the vaccination season it may be a little harder to find, he said.
Also encouraging is that the vaccine is a good match for the strains of flu circulating now, Skinner said.
Flu symptoms include fever, cough, fatigue, head and body aches, and runny nose. People at particular risk for flu and its complications are pregnant women, those 65 and older and anyone with a chronic illness. The CDC urges these people to get the flu vaccine, which is available as an injection or nasal spray and in a stronger dose for seniors.
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To learn more about the flu, visit the U.S. Centers for Disease Control and Prevention.