(USA TODAY) -- Today's flu shots aren't perfect -- but a "universal" flu vaccine
that works better and is longer lasting may not be far off, say health
In the midst of an early flu
season, health officials are urging unvaccinated people to still get a
flu shot as the best step they can take to protect themselves and their
The Centers for Disease Control and Prevention
said Friday that flu vaccines are about 62 percent effective. In the
past, it said 70 percent to 90 percent effective.
health circles, "there is a growing consensus ... that we need better
influenza vaccines," says Michael Osterholm, director of the Center for
Infectious Disease Research and Policy. "We're operating largely in the
1950s for our flu technology."
He published an influential
analysis in The Lancet last year showing flu shots are less effective
than commonly reported. For kids and people over 65, there are no
rigorous data showing their efficacy at all. But the intranasal flu
vaccine (FluMist) protects 83 percent of kids under 8, he found. There
is mixed evidence on how well it protects adults over 60, and little
evidence on effect in people 8 to 59.
In general, "the flu
vaccine is a good vaccine, but not a great vaccine," says William
Schaffner, a professor at Vanderbilt University School of Medicine.
says he strongly believes people should get yearly flu vaccines, given
their good safety record. And he says "moderate" protection is better
than none at all.
But drug companies have felt little
pressure to make truly "game-changing" vaccines because experts and the
public believe current shots are adequate. "The No. 1 deterrent to
getting new flu vaccines is the perception that the current ones are
good enough," says Osterholm, also a professor at the University of
Minnesota School of Public Health.
Today's flu shot, he
says, doesn't have much power to produce true "herd immunity," achieved
when enough people are immunized that the community's viral load drops,
protecting even the unvaccinated.
"The goal is to create a vaccine that you don't have to give every
year that works better," says Joseph Bresee, chief of the CDC's
epidemiology and prevention branch in its influenza division. "There's a
lot of research going on toward improving vaccines."
people need a flu shot every year because the virus is constantly
changing. Virologists try to predict which strains will be in
circulation, using those in the vaccine.
vaccine would be very different, producing immunity by including parts
of the flu virus that don't change from year to year, and which are
common among many strains of virus, Osterholm says. These should protect
people for a decade or more, stimulating the immune system to recognize
viruses it hasn't encountered for a long time.
In a 2011
interview with USA TODAY, National Institutes of Health director Francis
Collins said he was "guardedly optimistic" that a "universal" flu shot
could be developed within about five years.
vaccine is being tested in a small preliminary U.S. study. But the USA
should be doing more, Osterholm says. Developing a next-generation
vaccine could take 15 years and cost over $1 billion, he estimates.
But Schaffner says significant improvements are already being made.
year's flu shots should provide slightly broader protection. The
FluMist nasal spray will protect against four viral strains, instead of
three. Manufacturers of flu shots are also working to include four
Also, the Food and Drug Administration in November
approved the first flu vaccine made in cell cultures, rather than
chicken eggs. The vaccine, Flucelvax, made by Novartis, is approved only
The USA's current system -- a six- to
nine-month process that relies on fertilized chicken eggs to grow
viruses -- is "archaic," says Robert Glatter, an emergency medicine
physician at Lenox Hill Hospital in New York.
countries already use cell culture techniques, which allow companies to
produce vaccine far more quickly, Osterholm says, though it is no more
Glatter says companies face significant
obstacles in developing innovative flu vaccines, which must undergo
rigorous safety tests. They may see little point in developing a
universal vaccine, he adds. "If you get a mega-vaccine once every 10
years, the flu vaccine market would essentially be down-regulated, with
less financial market incentive."
Yet Glatter says the H1N1
pandemic flu in 2009 suggests that the human body is capable of
producing extremely long-term immunity from influenza. Senior citizens
had relatively low rates of infection, likely because they were exposed
to a similar virus in the 1930s and 1940s, he says.
goal is to make a vaccine that can confer such long-term immunity,"
Glatter says. "Such a feat would be a real breakthrough."