Friday December 15, 2006
Infant Wheezing And Rashes Linked To Toxins At Home
Endotoxins, produced by the breakdown of bacteria are everywhere. House dust typically contains large quantities of
these toxins. For the first time in New Zealand researchers at Otago University’s Wellington School of Medicine and
Health Sciences have found that endotoxins in the home are associated with wheezing and skin rashes in a large sample
(881) of infants under 15 months of age.
“This is an interesting result as it shows that endotoxins, which are extremely common in the environment, may be having
negative health effects on infants,“ says lead researcher Julie Gillespie. “Our main finding is that endotoxins taken
from the floor of a baby’s room at three months are associated with wheezing, and an itchy scaly rash up to 15 months of
age.”
The study, published in the Journal of Allergy and Clinical Immunology, found that children with higher levels of
endotoxin in their bedroom have more wheezing and more eczema like rashes, particularly if the child has a family
history of allergic disease. The influence of family history suggests that susceptibility to endotoxin is at least
partly inherited.
Wheezing and eczema in infancy are very common in New Zealand and exposure to endotoxin may be one of the reasons. Eight
out of ten New Zealand children also have one or other parent who has a history of allergic disease, which appears to
increase the effect of endotoxin.
“This may not all be bad news though,” says Professor Julian Crane, Director of the Wellington Asthma Research Group,
“There’s growing evidence that while endotoxin may cause wheezing by a direct effect on the lung, it may also protect
children from developing allergies in later childhood, and thus reduce their risk of allergic asthma”.
It remains to be seen, however, whether any of these early links between endotoxins in the home environment and
respiratory and skin symptoms, have any influence on the later childhood development of allergic disease such as asthma.
NZ has a high asthma prevalence rate by international standards.
“We have yet to measure the allergic asthma response at seven years of age with this cohort of children, “says Professor
Crane.
“At present we just don’t know about the longer term impact of endotoxins on asthma. But when we do this planned
research, it may help to explain whether or not exposure and reaction to endotoxins in early infancy has a positive or
negative effect on the development of asthma.”
This research was funded by the Health Research Council and the David and Cassie Anderson Bequest.
ENDS