After two relatively mild flu seasons, this year has quickly turned nasty, prompting Mayor Thomas M. Menino of Boston to declare a public health emergency Wednesday. Clinic waiting rooms are overflowing, and hospitals are scrambling to find beds for patients made miserable by high fevers, breathing problems, and dehydration.
The surge in cases comes despite a government recommendation three years ago that vaccination be expanded to everyone except infants under 6 months of age. Infectious disease specialists blame the particular virus strain that is circulating, which tends to cause worse illness, combined with the large percentage of people who have yet to be vaccinated.
Health care centers across the city will offer free vaccines this weekend to anyone who has not yet been immunized, and officials emphasized that it is not too late to get a shot.
“The best thing you can do to protect yourself and your family is to get the flu shot,” Menino said during a press briefing. “I’ve had my flu shot. I’m asking you to get yours, too.”
The city’s declaration of a health emergency was “very unusual,” said Dr. Anita Barry, director of Boston’s Infectious Disease Bureau. She said it was designed to raise awareness about the severity of the flu season and to make available public resources, such as providing health centers with vaccine.
The Whittier Street Health Center on Tremont Street in Roxbury was already offering free immunizations Wednesday, and director Frederica Williams said the clinic saw a surge in patients following the mayor’s announcement. She said the center was giving out three times the usual amount of vaccines for a January evening.
Spurred to action by the mayor’s declaration, John Cass, a father of two from Scituate, said he was going to try to get himself vaccinated on his way home from his office in Boston. But he was frustrated that the city issued the vaccine advisory before publicizing where free flu shots would be available.
The city has 700 confirmed cases of flu so far and four flu-related deaths. Last year, Boston had only 70 confirmed cases. Massachusetts has had 18 flu-related deaths this season, according to the state Department of Public Health.
“We’re off to an early start nationally and in Massachusetts,” said Kevin Cranston, director of the state’s Bureau of Infectious Disease. This flu season is on pace to be “moderately severe,” he said, but probably not unprecedented.
Officials from the US Centers for Disease Control and Prevention said they cannot explain why the flu season has hit early this year.
“The timing of the season is unpredictable” said Dr. Joseph Bresee, chief of the epidemiology and prevention branch in the CDC’s influenza division. “But this particular strain circulating leads to more severe disease with more deaths and hospitalizations.”
Area hospitals have restricted visitors in an effort to prevent the flu from spreading to patients. UMass Memorial Medical Center decided this week to ban visits from children age 14 and under, since they frequently contract the virus in school, and only allow patients to have two visitors at a time and only immediate family members.
“This is something we do during any type of outbreak,” said Dr. Robert Klugman, the hospital’s chief quality officer. “We had these restrictions when H1N1 was circulating,” he added, referring to the swine flu outbreak in 2009.
He said he has had no complaints from patients: “No one wants to be responsible for making someone ill,” he said.
Massachusetts General Hospital said its capacity has been “strained to its limits” with an additional 40 to 80 patients coming in daily to its outpatient clinics and emergency room with flu-like illness. The hospital has restricted visitors to its obstetrics department, filled with vulnerable, unvaccinated newborns and has urged all staff to stay home if they have a fever along with other flu symptoms.
Beth Israel Deaconess Medical Center had to open a previously closed wing to accommodate the influx of patients sick with the flu or the intestinal illness norovirus, which is also spiking.
While this year’s flu vaccine is well matched to the circulating viruses, including the more severe H3N2 strain that accounts for the vast majority of illnesses, public health officials emphasize that it is not 100 percent effective. A recent analysis from the University of Minnesota found that it probably protects about 60 percent of those who receive it.
“I felt like I was hit by a bus,” said Sarah Willey, a 37-year-old from North Attleborough who tested positive for the flu nearly three weeks ago, though she got a flu shot in September.
Jean Caldwell, 87, was hospitalized with the flu for four days at Baystate Medical Center in Springfield right after Christmas; she, too, had received the vaccine.
“At first I thought I was tired because of the holiday rush and that my asthma was acting up, but then I couldn’t breathe and had to head to the emergency room,” she said.
The vaccine “is not perfect, but it’s the best protection we have against influenza,” said Barry, of the Boston Public Health Commission . “We’re also encouraging people to stay home when they’re sick, to wash their hands frequently, and to cover their cough.”
The percentage of doctor visits statewide that are for flu-like illness — fever, body aches, coughing, runny nose, and fatigue — is now above 4 percent and is still climbing, according to the latest data from the Department of Public Health.
Last year, barely more than 1 percent of doctor visits were due to the flu at the season’s peak.
About 3 in 10,000 Americans over age 65 have been hospitalized with the flu so far this season, compared with 1 in 100,000 at the same time last year, according to the CDC.
Fewer than half of people nationwide receive the flu vaccine, according to the CDC. Vaccination rates in Massachusetts are a little higher, but not much. “We clearly have a long way to go,” Barry said.
Even health care workers have fairly low vaccination rates, about 65 percent nationwide, but rates have improved over the past two years in area hospitals that instituted mandatory vaccination policies, with exemptions for religious or medical reasons.
Nursing home facilities have been more reluctant to require staff members to get vaccinated despite the greater likelihood of severe complications and death in people over age 65. The flu vaccine is also less effective in older people, Barry said.
Employees at Marian Manor in South Boston, for example, were not required to get a flu vaccine when immunizations were offered at the facility in the fall. But the nursing home has asked residents’ family members not to visit until flu rates subside.
“What we’re telling people is that we’re strongly discouraging visitors at this time,” said Novyl Igo, assistant administrator of Marian Manor.
When this year’s flu season will reach its peak remains anyone’s guess. It could be occurring now or in the next few weeks, but the typical flu season lasts about 12 weeks from start to finish.
“Flu rates rocketed up in December,” said Barry, “so I won’t be surprised if this continues for another six to eight weeks.”
Andrew Ryan of the Globe staff and correspondent Chris Stuck-Girard contributed to this report. Deborah Kotz can be reached at firstname.lastname@example.org. Chelsea Conaboy can be reached at email@example.com.