The nationwide flu vaccine shortage has drawn attention to how
these vaccines are produced, with University researchers leading
the way in testing new vaccine options.

An alternative to the delivery of flu vaccines through shots is
the FluMist vaccine, developed by Hunein Maassab, epidemiology
professor at the School of Public Health.

The vaccine, which is inhaled through the nose, uses a weakened
live version of the influenza virus, unlike the injected vaccine,
which uses a dead version.

FluMist “stops the virus where it enters the body,
generally (through) the nose,” Maassab said.

A current study led by Public Health Prof. Arnold Monto compares
the effectiveness of the inhaled FluMist vaccines against the
injected forms. The study, called Flu-vacs, will involve 2,000
people in the Ann Arbor, Livonia and Mount Pleasant communities,
but it is not expected to be completed for about three years.

The FluMist technology has been licensed to be manufactured by
MedImmune for more than a decade, with the University receiving a
1.5 percent royalty on its sales. From this arrangement, the
University reaped $250,000 in royalties last year when FluMist was
introduced.

Although the introduction of FluMist was considered a failure
because of the surplus that was eventually disposed of,
MedImmune’s profile has been raised by the current vaccine
shortage. In a turnaround that will undoubtedly benefit the
University, MedImmune is slated to double the production of FluMist
to two million doses to help meet the unexpected national
demand.

Half of the U.S. supply of 100 million vaccines was lost this
year due to a manufacturing defect by one of the major U.S.
suppliers, Centers for Disease Control and Prevention Director
Julie Gerberding said in a news release.

Things went amiss this year in the manufacturing process, which
relies on incubating the viruses in millions of fertilized chicken
eggs. According to a company statement, the vaccine manufacturer
Chiron failed a safety inspection because of contaminations in the
process, leading to its vaccines being removed from the market.

Unlike other “one-time” vaccinations, a yearly shot
is necessary to stay immune to the flu. This is because the
influenza virus mutates each year into a different form that can
overwhelm the human body’s immune system.

The vaccines that protect against these viruses are then altered
each year to stay effective.

The vaccine itself is a culmination of a long process of
front-line investigation, scientific analysis and a fair amount of
guesswork, all of which happens nearly a year before the actual
start of each flu season.

Efforts to improve the manufacturing process of vaccines include
trying to replace the eggs with mammalian cell cultures to incubate
the viruses.

The engineering of hardier vaccines may eliminate the need for
vaccines to be refrigerated at every step of the manufacturing and
transporting process.

The World Health Organization tracks the yearly rise and spread
of new strains of the flu, which often originate in East Asia.
Health care providers pass along information on localized outbreaks
of new strains of flu, while keeping close watch for especially
lethal or easily transmitted strains. One such strain, a form of
bird flu, is especially deadly and of concern to scientists.

The virus, which made the leap from birds to humans, was
responsible for the slaughter of all live chickens in Hong Kong in
1997. It has also been identified this year in Vietnam, according
to a report in the New England Journal of Medicine.

A panel convened by the U.S. Food and Drug Administration votes
on which strains will be included in the final vaccine after
assessing the risks, lethality and contagiousness of each virus.
The resulting trivalent vaccine confers broad protection against
the three strains of influenza that stand the greatest chance of
affecting Americans.

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