Dust Mites

Uploaded by paloaltomedical on 17.06.2010

Hi, I'm Dr. Steve Rubenstein and today we're going to talk about dust mites. The number
one thing in the world for people to be allergic to are these lovely creatures called dust
mites, and 75 percent of people who are allergic are allergic to these little creatures that
are the main component of dust. The dust mites live on shed human skin. So, everybody makes
new skin and sheds old skin and where the dust mites live is not on you, but wherever
you shed your skin. And where you shed your skin the most is in bed. So, there are a lot
of good studies out there to show that a number of environmental measures can be taken to
minimize the impact of dust mites on people's noses, asthma and other allergies.
The dust mites are small enough that they get through the normal stitching in pillow
cases, mattress covers and so forth. And where they really accumulate is in the pillow, in
the mattress, and in the comforter. Therefore, getting new bedding frequently, theoretically,
can make a difference, but obviously it's impractical to get a new mattress or a new
comforter every month. So, the state of the art right now is to get these allergy covers
that have a stitching that's small enough that the dust mites cannot get through. Many
of these covers are available at places like Target or Macy's, but we do have catalogs
in which you can buy some of these products. The one I definitely recommend is for the
pillows. The pillow covers that you can buy at commercial outlets usually are noisy and
crinkly whereas the ones made by these allergy supply houses are nice and thin and they don't
make very much noise. They cost a couple dollars more, but it's definitely worth the money
to get those. Remember, new pillows are old in a month or two, so to get new pillows every
month doesn't make any sense, and to get these allergy covers is a very cost effective way
to try and minimize your allergies. When you put these covers on the pillows or on the
mattress, you also want to put the regular pillow cover or the regular mattress cover
on top of them. When those are washed, then it's important that you still take a damp
washcloth and go over the top of the allergy cover to wash away the dust mites that are
accumulated on top of that cover. It's also important that once you use a damp cloth to
wash those off that you dry that area off. Now, what I do recommend for people is the
more expensive pillow covers, but for the mattress you can buy less expensive ones either
from the allergy supply houses or by retail outlets locally. That takes care of the bed
and the pillow itself.
Next, are comforters. Comforters are bad. We hear a lot of bad things about down comforters,
but down really is no worse than polyfill. It's unwashed bedding that becomes a problem.
So, whatever's on the bed that you sleep with should optimally be washed every month. Sometimes
with comforters every two to three months is sufficient. But washing the comforter cover
itself is not good enough. It's inside the comforter where the dust mites accumulate.
So, optimally, people will have plain blankets that can be washed more easily every month,
but even if you have a comforter, you really want to try and wash it every month or two.
There are some old wives' tales that say that if you put tennis shoes or tennis balls in
the washer or dryer with the comforter, it potentially can make that comforter less lumpy
and bumpy once it's been washed. The one intervention I'll recommend is sometimes in the warmer
months to get some plain blankets and see you how you do, and then when the fall comes
around put the comforter on and see if you get worse, and obviously if you get worse,
then you know that you really have to be more aggressive with your bedding. Other interventions
in the bedroom can include making sure the bedroom is calm at bedtime; that's there's
no cleaning, straightening, closing curtains, wrestling with children jumping on the bed
for one hour before you go to sleep. Similarly, you should be out of a room for 45 minutes
to an hour after it's been cleaned or vacuumed. Cleaning and vacuuming more often certainly
can't hurt, but most studies have shown that doing it more often really does not help that
The other significant place for accumulation of dust mites are in couches. Leather couches
are better, but I certainly cannot tell people to go out and spend three to four thousand
dollars for a leather couch because the yield of improvement is very low. It's important,
however, that you don't lie down or nap on couches as much as possible. If you're going
to lie down, it's not a bad idea to put a sheet down to cover the couch and what's most
important is not to put the face into old couch pillows, whether that be on the couch
or the floor or wherever. A pillow from the bed that has an allergy cover on it, or a
leather pillow or a vinyl pillow is okay, but it's very important that the head not
go into old couch pillows or any of those square or rectangular pillows that you can
lie down on.
Next topic is humidifiers and vaporizers are generally bad. Dust mites thrive above 50
percent humidity and it's important that humidifiers are not automatically used. Humidifiers and
vaporizers will play a role in certain conditions called croup, but for general nasal secretions
or cough, we generally don't recommend humidifiers or vaporizers for allergic people. If it's
really dry when the heat's on then nasal saline sprays that you can buy over the counter,
such as Ocean Spray or Ayr Spray can be just as effective without creating a dust mite
or even moldy environment.
Other things that are preferable if possible is to wash bedding in hot water. It turns
out it's not as essential to wash in hot water as we thought it used to be, it's more the
frequency of washing bedding that's important, but if you can wash pillow covers and sheets,
and even blankets in hot water, that's probably preferable.
The other interventions which always are a source of controversy are air filters. Good
air filters are very expensive. No study has ever shown that air filters reduce symptoms
although they certainly can reduce the amount of dust in the air. Good air filters such
as HEPA filters cost three to four hundred dollars. And if things are going well with
your allergy care or all the other interventions you've tried, it's certainly worth maybe trying
an air filter for a month or two, but if there's no improvement I frequently recommend, and
don't tell this to anybody, taking the air filter back. You may have heard about something
called an ionic breeze which is a little bit more money and it's like a HEPA filter but
doesn't make as much noise. It's similar that if you want to try and spend the money for
that, you may but usually these interventions are not worth the money. Air filters for the
furnace are important to change once a year and maybe once during the winter months, but
to buy fancy air filtration systems or to clean out duct systems, usually is not worth
the money. The same can be said for carpets.