So far this flu season, 2,257 people have been hospitalized with laboratory-confirmed flu. Eighteen children have died.
The number of deaths attributed to both pneumonia and the flu is still below epidemic levels.
How much worse will it get? When will it be over? No one can say.
"Seasonal flu is a big deal -- always. It's always going to be a problem. This year may be a very big problem," says William Hanage, PhD, an associate professor of epidemiology at the Harvard School of Public Health in Boston. "We don't know yet."
Most flu seasons last about 11 to 12 weeks. "We're at about week five," says Curtis Allen, a press officer at the CDC. "Even that 11 to 12 weeks is not a hard and fast number. The saying in the influenza world is that if you've seen one flu season, you've seen one flu season. Each one is different."
Northeast Hit Hard
Across the Northeast, emergency rooms have seen an influx of patients showing flu-like symptoms. In some cases, patients who come in coughing are being directed to other areas, including outside tents, to keep them from infecting others.
"We're opening additional work spaces and areas to take care of patients," says Robert Glatter, MD, an emergency doctor at Lenox Hill Hospital in New York City. "It's almost as concerning as the 2009 outbreak of H1N1. We're getting concerned about the severity, especially because of how ill people are."
Since Christmas, Glatter says Lenox Hill has seen a spike in flu cases. Many of the victims are elderly and their symptoms tend to be severe: aches, chills, cough, fevers, dizziness, nausea, vomiting, and diarrhea.
Already, Boston has had 10 times as many confirmed cases as it had last year, prompting the city's mayor to declare a public health emergency there. Health centers around the city are offering free flu shot clinics to those people who haven't yet been vaccinated.
That offer may be good only while supplies last, however. The health department in Somerville, a Boston suburb, says it ran out of flu vaccine on Tuesday.
On Thursday, Sanofi SA, the largest flu vaccine manufacturer in the U.S., confirmed that it had sold out of four of the six formulations of Fluzonevaccine, including a dosage that's given to children. Another manufacturer, GlaxoSmithKline, says it expects to have adequate doses of its vaccine for another month.
Roche says the liquid form of Tamiflu, which is mostly prescribed for children, is in short supply. Roche is sending out new supplies as they become available. Pharmacists can make a substitute by crushing tablets and mixing them with a sweet liquid, however.
Still, the FDA says there's no reason for concern, though people may find they have to call around to find a flu shot.
"It is not unusual for there to be occasional spot shortages, especially this late in the 2012-13 vaccination campaign. The overall supply of vaccine is believed to be sufficient unless the demand is much higher than previous years," says Rita Chappelle, a press officer in the FDA's Center for Biologics Evaluation and Research.
Get the Shot
The good news is that it's not too late to get vaccinated.
"It does take two weeks to reach peak antibody levels, but prior to reaching that optimal level, you're still getting some protection," Glatter says.
So far, the vaccine appears to be a good match to the circulating strains of virus.
Glatter says it's important to remember that even if you've had a flu shot, it's not 100% effective at preventing illness.
For that reason, he says frequent and thorough hand washing is a must. After drying your hands, hit them with a good pump of alcohol-based hand sanitizer. "They should be at least 60% alcohol," Glatter says. "Those are the most effective against viruses."
And if you're starting to feel bad, Glatter says, "Stay home. Don't go to school or work."
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