NEW YORK (AP) -- From the Rocky Mountains to New England, hospitals are swamped with people with flu symptoms. Some medical centers are turning away visitors or making them wear face masks, and one Pennsylvania hospital set up a tent outside its ER to deal with the feverish patients.
Flu season in the U.S. has struck early and, in many places, hard.
While flu normally doesn't blanket the country until late January or February, it is already widespread in more than 40 states, with about 30 of them reporting some major hotspots. On Thursday, health officials blamed the flu for the deaths of 20 children so far.
Whether this will be considered a bad season by the time it has run its course in the spring remains to be seen.
"Those of us with gray hair have seen worse," said Dr. William Schaffner, a flu expert at Vanderbilt University in Nashville.
The evidence so far points to a moderate season, Schaffner and others say. It looks bad in part because last year was unusually mild and because the main strain of influenza circulating this year tends to make people sicker and really lay them low.
David Smythe of New York City saw it happen to his 50-year-old girlfriend, who has been knocked out for about two weeks. "She's been in bed. She can't even get up," he said.
Also, the flu's early arrival coincided with spikes in a variety of other viruses, including a childhood malady that mimics flu and a new norovirus that causes vomiting and diarrhea, or what is commonly known as "stomach flu." So what people are calling the flu may, in fact, be something else.
"There may be more of an overlap than we normally see," said Dr. Joseph Bresee, who tracks the flu for the Centers for Disease Control and Prevention.
Most people don't undergo lab tests to confirm flu, and the symptoms are so similar that it can be hard to distinguish flu from other viruses, or even a cold. Over the holidays, 250 people were sickened at a Mormon missionary training center in Utah, but the culprit turned out to be a norovirus, not the flu.
Flu is a major contributor, though, to what's going on.
"I'd say 75 percent," said Dr. Dan Surdam, head of the emergency department at Cheyenne Regional Medical Center, Wyoming's largest hospital. The 17-bed emergency room saw its busiest day ever last week, with 166 visitors.
The early onslaught has resulted in a spike in hospitalizations. To deal with the influx and protect other patients from getting sick, hospitals are restricting visits from children, requiring family members to wear masks and banning anyone with flu symptoms from maternity wards.
One hospital in Allentown, Pa., set up a tent this week for a steady stream of patients with flu symptoms. But so far "what we're seeing is a typical flu season," said Terry Burger, director of infection control and prevention for the hospital, Lehigh Valley Hospital-Cedar Crest.
On Wednesday, Boston declared a public health emergency, with the city's hospitals counting about 1,500 emergency room visits since December by people with flu-like symptoms.
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 suffered her worst case of flu-like illness in years and was laid up for nearly a month with fever and body aches. "I just couldn't function," she said.
She decided to skip getting a flu shot last fall. But her daughter got the shot. "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.
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.