Is the H1N1 Swine Flu Vaccine Safe?
H1N1 Swine Flu Vaccine Safety: Hype, Myths, and Facts
Is the 2009 H1N1 swine flu vaccine safe? continued...
That's still not proof that no harm will come from the vaccine. Clinical
trials cannot detect something bad that happens to one or two out of every
100,000 people vaccinated.
"There could be unknown side effects. Something could happen. But we think
that is highly unlikely," says infectious disease and vaccine expert Mark
Mulligan, MD, executive director of the Hope Clinic of the Emory Vaccine Center
"The CDC, FDA, HHS [Health and Human Services Department], the Department of
Defense, and several large HMOs with great medical records are all
collaborating in enhanced surveillance for this national 2009 H1N1 vaccine
campaign," Mulligan tells WebMD. "If there is a signal for a rare or late
adverse event, we will identify it as early and as quickly as we can."
Isn't the 2009 H1N1 swine flu vaccine too new to trust?
Is the swine flu vaccine brand new? Yes and no. The 2009 H1N1 swine flu
vaccine is made exactly the same way as the seasonal flu vaccine, by the same
manufacturers using the same materials -- except for one shiny new piece.
What has changed is the piece of the virus the vaccine uses to prime the
Vaccine experts tell WebMD this change isn't all that new. Every couple of
years or so, a new variant of a seasonal flu virus comes along. When that
happens, a "new" vaccine is made using the relevant part of the variant
And even though the 2009 H1N1 swine flu is a genuinely new virus, it's still
closely related to seasonal flu bugs. One of the vaccines in the three-in-one
seasonal flu vaccine protects against seasonal H1N1 flu, which is about 75%
similar to the 2009 H1N1 swine flu -- although it offers no protection against
the pandemic flu.
Last year, some 100 million people got the seasonal flu vaccine. No safety
issues appeared. That's reassuring, but it's no proof that something rare and
unexpected can't happen.
There's no denying that the virus particle used in the vaccine has never
been used before. No scientific calculation can rule out the chance that
something unexpected might happen.
But one can calculate that this chance will be small. And the chance that
the vaccine will prevent serious illness and deaths is very, very large.