Flu season let state off easy, this year
Vaccine plentiful, amount of illness ‘average’ in Mass.
There was no widespread panic. No shortage of vaccine. After the H1N1 pandemic that dominated last year, disease trackers in Massachusetts and nationally said the flu season now coming to a close was as routine as they come.
“The vaccine was ample, it was available early, and the amount of disease we had was very, sort of, average,’’ said Dr. Alfred DeMaria, state epidemiologist in Massachusetts. “It’s always bad, but it was average-bad. And it occurred at the time when we usually see influenza, which is February into March.’’
Even in a comparatively mild season, influenza can kill thousands of people and sicken millions. But compared with the unexpected swine flu scare of 2009-10 or prior years in which moderate infection rates were complicated by problems in vaccine supply, this season was almost mild, DeMaria said.
Manufacturers added the swine flu strain to the seasonal vaccine and produced a record amount — 160 million doses, up from an average of 113 million over the previous three years.
Early projections from the US Centers for Disease Control and Prevention show that about 42.6 percent of people nationwide got the shot, compared with 32.6 percent two years ago. It is difficult to compare those figures to demand last year because people were offered two different shots — against the seasonal strains and the new swine flu strain — but there were shortages of both.
National infection rates were well below what they were at the height of swine flu in October 2009, when 7.7 percent of visits to doctors were attributed to flu-like symptoms. This season’s peak came in mid-February, when that figure was 4.6 percent.
Among Boston residents, there were 758 confirmed flu cases between last November and the end of March, including 198 people who were hospitalized, said Anita Barry, director of the Infectious Disease Bureau of the Boston Public Health Commission.
In 2009, 1,651 people in Boston were confirmed to have contracted swine flu. Those cases only provide a tiny window into the flu season, however, because the majority of people with the flu never see a doctor.
Massachusetts may have escaped the worst of it this year. Southeastern states were hardest hit, according to a CDC flu tracker, while infection rates in New England were mostly mild to moderate.
Dr. Dan Jernigan, deputy director of the CDC Influenza Division, balks slightly at the characterization of any flu season as “mild.’’
And while there was less infection this season, in one way, it was more intense.
A flu strain that first appeared in 1968 and was virtually squeezed out last year by the prevalence of swine flu rebounded this year, making up about 39 percent of lab-tested samples. That strain is particularly virulent and is problematic for older people, Jernigan said.
Specialists said higher vaccination rates, fueled in part by greater public awareness from the swine flu outbreak, helped to control overall infection this year.
“Flu has been gaining recognition steadily for a little more than a decade . . . as a cause of serious illness, especially for the young, the old, and people with underlying illnesses,’’ said Dr. Benjamin Kruskal, director of infection control for Harvard Vanguard Medical Associates, one of the largest medical practices in Massachusetts.
He oversees ordering and distribution of vaccines for more than 500 physicians. This year, the group bought 116,263 doses, a 22 percent increase from two years ago. Kruskal did not know how many may have gone unused, but he said he expects to place a slightly larger order for next season.
Last year, the CDC expanded its recommendations about who should get vaccinated from just those most vulnerable to complications from the flu to everyone older than 6 months. And consumers had more options as pharmacies at big box stores and supermarkets offered the shots more regularly to shoppers.
The memory of the swine flu scare may fade, specialists cautioned. The trick is getting more people to make vaccination a part of their annual routine, said Dr. Jacques Carter, a Beth Israel Deaconess Medical Center primary care physician.
“We beat the drum about flu vaccines every year,’’ he said. “It’s the same drumbeat. Maybe that’s the problem.’’
Jernigan said he expects to get a better sense from manufacturers in coming weeks about how much vaccine they will produce for the next round. As for how intense the coming season will be, no one can tell, he said.
Influenza is “exceptionally variable from year to year and by geography,’’ Jernigan said. “It can be a maddening infection to monitor because it is constantly changing.’’
Chelsea Conaboy can be reached at cconaboy@boston.com. 
