|This 2009 file microscope image originally provided by the Centers for Disease Control and Prevention, shows a negative-stained image of the swine flu virus.
BOSTON - With flu cases in this city up tenfold from last year, the mayor of Boston declared a public health emergency on Wednesday as authorities around the United States scrambled to cope with a rising number of patients.
Health authorities say a virulent strain this year has caused the number of flu cases to surge earlier than usual. Hospitals around the country have scrambled to find additional space to treat the ill, and some have had to turn people away.
Mayor Thomas Menino said the number of reported infections in Boston is already 10 times higher than last season's reported caseload, and said the city would begin offering free flu vaccinations on Saturday in an effort to stem the spread.
"The latest reports show an increasingly tough flu season," Menino told reporters. He urged residents to get vaccinated, saying, "We are less than halfway through the flu season."
The flu season typically picks up in December, builds to a peak in January or February and fades away by late March or early April.
The U.S. Centers for Disease Control and Prevention reported that the proportion of people visiting their doctors for flu-like illnesses has doubled in the past four weeks.
The CDC does not track all cases of flu. The number is difficult to pin down since not all people who develop symptoms seek medical attention.
Encouraging vaccinations is one of the most effective steps in combating what looks to be a serious strain of the flu, said Dr. William Hanage, an associate professor of epidemiology at the Harvard School of Public Health.
"This is a bad year, there's no question about it. It's going to be, at minimum, moderately severe," Hanage said, adding that the outbreak looks less severe than in 2009 when the dominant strain was the H1N1 swine flu.
The A(H3) strain of flu, which CDC data shows is the most commonly diagnosed this year, tends to bring more severe illness and a longer flu season.
In Illinois last week, large numbers of sick people overwhelmed some hospitals, and 24 facilities had to turn away some sick people, more than triple the seven hospitals that turned patients away in the same week last year.
"We've been told that a lot of it has been due to upper respiratory, influenza-type illnesses. Not 100 percent of it. But there are indications that a lot of it is flu-related," said Melaney Arnold, a spokeswoman for the Illinois Department of Public Health.
Lehigh Valley Hospital, outside Allentown, Pennsylvania, on Tuesday set up a large tent outside its emergency room, which it is using to see patients who arrive with less-severe flu cases, said hospital spokesman Brian Downs.
"What we're trying to do is sort of help some of that extra burden that is put on the emergency room because of the extra patients that are coming in with flu," said Downs, who estimated that daily visits to the hospital's emergency department are up about 30 percent due to the flu.
In Maine, health authorities reported a "significantly higher" than normal number of flu cases and warned residents this week to expect flu activity to remain high for the next few weeks.
In North Carolina, flu activity has been recorded at the highest levels in a decade with 14 deaths. Many hospitals there have tightened restrictions on visitors. One company, Carolinas HealthCare System, said it would restrict most visitors under age 12 from Charlotte-area hospitals starting on Thursday after a spike in emergency department visits for flu-like symptoms.
In Weymouth, Massachusetts, outside Boston, South Shore Hospital received approval from state regulators to move patients ahead of schedule into 10 rooms it was renovating to accommodate the influx.
Job-consulting firm Challenger, Gray & Christmas warned that the weak economy could cause the outbreak to spread more quickly because some Americans are reluctant to stay home from work.
"Whether it is motivated by job security or a desire to continue making a contribution in an overburdened workplace, "presenteeism," as it has come to be called, only spreads illness to more workers and further damages the employers' ability to meet demand," said John Challenger, the firm's chief executive.
Public health officials urged people to stay home from work or school if they become ill, but not necessarily to rush to the hospital, particular if they are between the ages of 5 and 65 and otherwise healthy.
"What we don't want ... is people just pouring into the emergency departments, we would really like people to contact their health care provider," said Dr. Barbara Ferrer, executive director of the Boston Public Health Commission.