>>Hi, my name’s Paul Offit. I’m talking to
you today from the Vaccine Education Center here at The Children’s Hospital of Philadelphia.
Some parents are concerned, I think reasonably, you know, now that we’re sort of giving all
these vaccines, and we’re preventing so many infectious disease, “Could that put my child
at risk for allergies like asthma, for example?” And I think where that comes from is the fact,
and it’s true, that you’re much more likely, for example, to have asthma if you live in
an industrialized, Western nation, like the United States, than if you live in a country,
say in Africa, which is far less industrialized. And the reason for that is the so-called hygiene
hypothesis. Which is to say because children in the developing world are more likely to
be exposed earlier in their life to viruses and bacteria, including toxin-producing bacteria,
and fungi, and parasites, that they have a lesser incidence of asthma. Could it be possible
that because we’re making for a “cleaner” environment in the United States, if you will, by giving
vaccines that we’re increasing the risk of asthma? And the answer to that question is no for
a couple of reasons. One is that if you look at the viruses, for example, that are prevented
by vaccination, they are transmitted independent of the level of hygiene in a home or sanitation
in the country. And, frankly, there’s still, unfortunately, plenty of other viruses and
bacteria that affect children for which we don’t have vaccines. Viruses like coronaviruses,
or astroviruses, or caliciviruses, or parainfluenza viruses, or respiratory syncytial viruses.
So, sadly there are still plenty of ways that one is exposed to infections in the United
States for which we don’t have vaccines. So, I think while the hygiene hypothesis,
if you will, is true, I think it really has nothing to do with vaccines. Thank you.