No longer pandemic, H1N1 flu still hangs on in new flu season

With frantic efforts to gird for the 2009 H1N1 influenza pandemic still etched on the public mind, some health officials have been gearing up weeks earlier than usual to do battle with the 2010 flu season.

This year there is no H1N1 pandemic. It was officially declared over by the World Health Organization a few weeks ago. But H1N1 flu is still floating around, as are two seasonal strains -- H3N2 and Type B -- expected to be prevalent in the U.S. this autumn and winter.

All three have the potential to unleash local epidemics that can hospitalize or even kill some sufferers, and all are included in this year's vaccine -- meaning that people don't have to get a separate H1N1 shot.

It's too soon to know whether consumers will have the same concerns about the seasonal flu shot that they had over last year's stand-alone H1N1 vaccine.

"There is a saying in medicine that if you have seen one flu season, you have seen one flu season," said William Schaffner, a Vanderbilt University specialist in preventive medicine who advises the CDC on immunization.

"It is a very unpredictable disease from one year to the next," he said. "The psychology behind public acceptance of being vaccinated is very unpredictable from year to year, also."

The federal Centers for Disease Control and Prevention this year has simplified its recommendations of who should be vaccinated to include all Americans six months old or older. Last year it said the seasonal vaccination should be considered "optional" for healthy people between 18 and 64 years old.

Also this year for the first time, seniors are being offered a super shot called "Fluzone High-Dose" to boost their immune systems. It is four times more potent than the normal flu shot because it contains four times the flu-fighting antigens of the standard vaccine.

The souped-up formulation for seniors has the approval of the federal Food and Drug Administration, which is monitoring it closely this season to determine its efficacy. The CDC in its vaccination guidelines has left the option open for seniors to try it or not without making a recommendation either way.

Schaffner noted that the high-dose formula has a slightly higher percentage of recipients reporting minor side effects, including soreness in the area of the injection and getting a slight fever that is gone within 24 hours.

"Because it is four times as strong, there is a little more 'Ouch!' that comes with the high-dose formula with a few recipients," Schaffner said.

Federal officials say in general, this year's vaccine is so plentiful that everybody who wants it should be able to get it in a timely manner.

Vaccine manufacturers have geared up to produce between 160 million and 165 million seasonal flu vaccine doses and began delivering them in August.

"Flu is a very serious disease," said Dr. Julie Morita, Chicago's deputy health commissioner, pointing out it hospitalizes hundreds of thousands of people every year and on average causes 24,000 deaths nationally. "Our best defense against it is getting vaccinated."

A year ago last April, H1N1 dramatically appeared on the world stage as the first worldwide pandemic flu in 40 years, a serious threat because pandemic flu is particularly lethal to children and young adults.

Researchers developed a separate vaccine for H1N1, which meant people needed to be vaccinated separately for H1N1 and for seasonal flu. Because of production problems, supplies of the H1N1 vaccine were limited last October and November, just as the virus peaked, causing a noisy public clamor for the shots.

For seasonal flu, every year health authorities make an educated guess to formulate a "cocktail" vaccine to fight off the three flu strains they believe pose the biggest risk to sickening large numbers of people.

The flu season strikes first in Southern Hemisphere nations, peaking in May, June and July, offering early insight into whether our seasonal vaccine is accurately formulated before the flu moves north and peaks in November, December and January.

Some years the formulation goes after the wrong flu strains. The vaccine formulation for this year seems to be accurate, judging from what happened in the Southern Hemisphere last summer, Schaffner said.

"We anticipate this will be a conventional flu season, whatever that is," he said.

Since 1976, the numbers of deaths each year from seasonal flu range from 3,000 to 49,000. Last year more than 12,700 died, most of them from H1N1 rather than seasonal flu.

Last year many people, including some health care workers, refused to take the H1N1 vaccine, claiming it was an experimental vaccine rushed into production without adequate testing for safety and possible adverse side effects, even though it was made in the same way as seasonal vaccines, which have a sterling safety record over several decades.

A total of 125.5 million H1N1 doses were administered between August 2009 and January, Shaffner said, and "it behaved exactly as the way seasonal vaccine behaves, a consummately safe vaccine."

With that track record, designers of this year's seasonal vaccine thought even those who refused the H1N1 vaccine last year would accept it this year and included it as one of the seasonal vaccine's three targeted viruses. Shaffner said so far there is no indication of whether last year's doubters will accept it.

For those who were vaccinated for H1N1 last year, being revaccinated for it this year will cause no harm, according to CDC guidelines.

While CDC guidelines urge everybody 6 months and older to be vaccinated, it continues to emphasize that certain groups of people are more vulnerable to flu than the general population and especially urges people in those categories to be vaccinated. They include:

All people age 65 and older.

• Children younger than 5, but especially children younger than 2. Any child under 9 who has never been vaccinated for flu needs two vaccinations to achieve sufficient immunity.

• Pregnant women.

• All people with long-term health conditions such as asthma, obesity, diabetes or with neurological, kidney, liver or heart and lung diseases.

• People with weakened immune systems due to disease or medications.

• American Indian/Alaska Natives.

Beyond infants younger than 6 months, the major exclusion from receiving the vaccine is people with severe egg allergies, because the vaccine is cultured in chicken eggs.

Last year the federal government paid for the manufacture of every H1N1 vaccine dose, so it was often available for free, but seasonal flu shots must be paid for by the recipient.

"This year goes back to normal," said Melanie Arnold, spokeswoman for the Illinois Department of Public Health. "Doctors offices and local health departments order the vaccine, and typically there is a charge for it. Some insurance companies will cover the cost of the vaccination, but people should consult their plans."

Most health departments urge people to consult their doctor for a flu vaccination, but the shots are now widely available outside doctors' offices and clinics, particularly in retail pharmacies such as Walgreens and CVS and in department store pharmacies such as Target and Walmart.

The shot costs about $30 for the shot in retail outlets, most of which accept many insurance plans for payment.

(c) 2010, Chicago Tribune.
Distributed by McClatchy-Tribune Information Services.