National Study Shows Dog and Cat Allergens are Universally Present in U.S. Homes
Scientists at the National Institute of Environmental Health Sciences
(NIEHS), one of the National Institutes of Health, and the U.S.
Department of Housing and Urban Development have found that detectable
levels of dog and cat allergens are universally present in U.S.
homes. Although allergen levels were considerably higher in homes
with an indoor dog or cat, levels previously associated with an
increased risk of allergic sensitization were common even in homes
without the pets.
This report by Arbes et al., which will appear in the July
2004 issue of the Journal of Allergy and Clinical Immunology, is
one of a series of allergen reports from the National Survey of
Lead and Allergens in Housing. In that nationally representative
survey of 831 homes, researchers collected dust samples, asked questions,
and examined homes.
Interestingly, the researchers found that dog and cat allergen
levels were higher among households belonging to demographic groups
in which dog or cat ownership was more prevalent, regardless of
whether or not the household had the indoor pet. Because dog and
cat allergens can be transported on clothing, the researchers speculated
that the community, particularly communities in which dog or cat
ownership is high, may be an important source of these pet allergens.
For pet-allergic patients in such communities, allergen avoidance
may be a difficult challenge.
The survey was conducted using established sampling techniques
to ensure that the surveyed homes were representative of U.S. homes.
The homes were sampled from seventy-five randomly selected areas
(generally counties or groups of counties) across the entire country.
The 831 homes included all regions of the country (northeast, southeast,
midwest, southwest, northwest), all housing types, and all settings
(urban, suburban, rural). For statistics derived from the 831 homes,
the contribution from each home was weighted as necessary to ensure
that the statistics were representative of the U.S. population.
Until now, exposure to these allergens had not previously been studied
in residential environments on a national scale.
NIEHS conducts and supports research to reduce the burden of
human illness and dysfunction from environmental causes by understanding
environmental factors, individual susceptibility and age and by
discovering how these influences interrelate.
For further information on study:
Dr. Samuel Arbes, NIEHS scientist, 919-541-0981
Dr. Darryl Zeldin, NIEHS scientist, 919-541-1169