12th February 2004
Medical
New York - Small babies who spend their first year around
dogs may have a lower risk of developing allergies, a new study has found.
Having a cat, however, did not appear to do anything for allergy risk, a
Reuters Health report yesterday said.
However, study author Dr James Gern, of the University of Wisconsin, warned
that it was too early to say whether every household should have a dog.
The study found only that children who lived with dogs tended to have less
eczema, a skin rash associated with asthma and allergies.
Dog owners were also less likely to develop a protein involved in allergies,
and tended to show higher levels of susbtances that may help the blood resist
allergic reactions.
Dogs also tend to be dirtier than cats, Dr Gern said, and licked people more,
and exposure to dirt early in life may help kick the immune system.
"Understanding what factors - like pets - in the environment contribute to
healthy immune development will hopefully point the way to new types of
preventive treatments for allergic diseases," he said.
The reason some children develop allergies and others don't are often a
mystery, he said, and past studies on pets have shown mixed results.
As for pet cats, an earlier report, from the National Institutes of Health in
2002, said that for many years, scientists thought that cat exposure increased
a child's asthma risk.
Other studies, however, suggested that being around cats during infancy can
protect against asthma.
Then another one said that cats have this effect in all cases except when the
child's mother had asthma, in which case having a cat at home actually tripled
the risk that a child would develop asthma by age five.
Dr Juan Celedn, who led the NIH research, at Brigham and Women's Hospital,
said: "For years, physicians have been
advising families with allergies to stay away from pets. However, it appears
that for a vast majority of children, being exposed to a cat early in life may
be beneficial."