In 1989 a group of doctors did a study which was published in the New England Journal of Medicine in 1990. It involved 67 children from Poole, England, they found that in addition to genetic factors, exposure in early childhood to house-dust mite allergens is an important factor in the later development in asthma.1 There were a few studies shortly after that confirmed these results.
Due to some complications with the study at the time they were not sure whether or not to include pet allergen avoidance. The presence of pets within the study area was too high to determine if their theory about pet allergens being a deterrent in asthma was correct. They also did not have the same knowledge we do today of immunotherapy.
In addition to this study there was another one posted in the New England Journal of Medicine in 1997 that concluded cockroach allergens in urban areas also are a factor in the occurrence of asthma in children.
There are many other factors in the development in asthma, this is just one item researched among many and is intended to be educational. 2
Exposure to House-Dust Mite Allergen (Der p I) and the Development of Asthma in Childhood — A Prospective Study
Richard Sporik, M.R.C.P., Stephen T. Holgate, M.D., F.R.C.P., Thomas A.E. Platts-Mills, M.D., Ph.D., and Jeremy J. Cogswell, M.D., F.R.C.P.
N Engl J Med 1990; 323:502-507August 23, 1990DOI: 10.1056/NEJM199008233230802
The role of cockroach allergy and exposure to cockroach allergen in causing morbidity among inner-city children with asthma.
Rosenstreich DL, Eggleston P, Kattan M, Baker D, Slavin RG, Gergen P, Mitchell H, McNiff-Mortimer K, Lynn H, Ownby D, Malveaux F.
N Engl J Med. 1997 May 8;336(19):1356-63.