An early outbreak of influenza sweeping through the Washington area this week is overwhelming hospitals and physicians, part of a broad wave of sickness along the East Coast that has caught health authorities off guard with its speed and severity.

At Washington Hospital Center in the District, emergency room traffic set new records for three days in a row, as tides of desperate flu sufferers flooded the facility starting Sunday.

At other hospitals in the Washington and Baltimore areas, doctors have been forced to board noncritical patients in waiting rooms or send them elsewhere.

And from New England to Georgia, the demand for over-the-counter flu remedies is so strong that many pharmacies are running out.

"This is the busiest flu season we've seen in some time," said Mike DeAngelis, spokesman for the Rhode Island-based CVS drugstore chain. "The speed of this thing is just unbelievable."

The rapid advance of the virus eastward, from its December onslaught in the West, has led some doctors and patients to wonder whether a mutant strain is bypassing the flu shots widely given to combat the problem. But health officials caution there is no laboratory evidence to support that theory. The shots are still the best defense against getting sick, and physicians are recommending them for everybody over 65 and chronically ill younger people.

The local outbreak has been especially severe in Maryland, where 11 hospitals--including five in suburban Washington--remained on "yellow alert" yesterday. Those hospitals were referring many patients to other hospitals and canceling non-emergency surgeries to free up beds.

Jeff Roche, the acting state epidemiologist for Maryland, said most patients have coughs, sore throats, heavy congestion and other respiratory ailments--including some cases of potentially fatal pneumonia. In addition, Roche said, physicians have reported an unusually high number of gastrointestinal disorders, such as vomiting and severe diarrhea.

"There seem to be more people coming through the door than in earlier years," Roche said. "It seems to be kicking in pretty hard right now."

In Virginia, state health officials say the flu outbreak is most pronounced in the northern and southwestern reaches of the state. Hospitals throughout Northern Virginia report surging numbers of visits to emergency rooms, including volumes up to 60 percent above normal at three facilities in the Inova Health System. Inova Fairfax Hospital, which normally sees 185 emergency patients a day, has had as many as 253 a day this week, according to spokeswoman Janice Moore.

District resident Calvin Burnette, 32, was on his way to work at C&B Drywall with his girlfriend yesterday when he said he couldn't drive anymore. Hours later, he found himself in a wheelchair in the Inova Fairfax emergency room, waiting to see a doctor.

"My head was hurting, and I was feeling a little dizzy" Wednesday, Burnette said. "Now, when I cough a lot, I get dizzy and my body's aching."

Although many patients have sought help in emergency rooms, physicians say that home in bed is the best place for most of those afflicted--drinking fluids and taking over-the-counter medication to reduce fever and relieve achiness.

Richard Alcorta, head of Maryland's Emergency Medical Resource Center, said hospitals and ambulances have been struggling all week to cope with thousands of flu sufferers, many of whom are at risk of serious complications because of other chronic respiratory illnesses. At one point Monday evening, 19 of the 24 emergency rooms in the Baltimore area were turning away patients with noncritical problems.

Alcorta and other officials warned that once it begins, the flu season usually lasts six to eight weeks.

"We are really only into the second week of this," Alcorta said. "We are just starting to hit our peak now. . . . It looks like we may see an increase in numbers this year, but we can't say for sure yet."

Barbara Davis, of Damascus, said she came down with a severe case last week despite having gotten a flu shot, and she wondered whether she was infected with a strain of influenza virus that's not covered by this year's vaccine.

"This is Day 8," said Davis, 42. "I got it big time. It's like a massive cold with a fever that just won't go away, and aches and chills and pains. . . . I think I've blown my nose 50,000 times over the past week."

Vincent Vaghi, a Germantown allergist, said a number of his asthmatic patients, including Davis, who received flu shots last fall seem, nevertheless, to be coming down with what looks like influenza.

"I think it's just a small percentage that it's not covering," Vaghi said. "The question is, is there some strain out there that is causing this that was not included in the vaccine?"

So far, however, epidemiologists at the Centers for Disease Control and Prevention in Atlanta have no evidence that this winter's epidemic is worse than normal or that the flu vaccine is less effective than expected.

Through mid-December, about 99 percent of samples gathered in both North America and Europe were members of the broad family known as influenza A. Nearly all were either identical, or very similar, to one of the three virus strains used in the current vaccine. In examining flu samples, CDC virologists pay especially close attention to those taken from people reported to have been immunized.

To date, "no novel strains of virus have appeared," said Nancy J. Cox, chief of the CDC's influenza branch.

The agency was finishing tests last night on about 100 samples received in the last two weeks. Those results, to be released today, will help answer the question whether anything unusual is happening to make the epidemic more widespread or virulent.

Even in young, healthy people, the vaccine prevents infection only 70 to 90 percent of the time. In the elderly, the effectiveness is substantially lower, though it lessens the severity of illness.

Staff writers David Brown, Jennifer Frey, Steven Gray, Sylvia Moreno and Christina A. Samuels contributed to this report.