Younger siblings and MS

[Guest guest]

Hi All,

Having younger three brothers and a sister, I enjoyed:

C B C . C A N e w s - F u l l S t o r y :

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Younger brothers, sisters may help protect against MS

Last Updated Tue, 25 Jan 2005 20:23:20 EST

CBC News

Last Updated Tue, 25 Jan 2005 20:23:20 EST

CBC News

CHICAGO - Children who are exposed to infection from a younger

sibling may be better able to fight off multiple sclerosis later in

life, a new study suggests.

According to the " hygiene hypothesis, " exposure to infections early

in life from household dust or germy siblings may reduce the risk of

developing certain diseases in adulthood.

It's thought that improvements in sanitation and health care in the

developed world may be linked to the increasing prevalence of

multiple sclerosis.

In the autoimmune disease MS, scientists say the body's overactive

immune system attacks the protective sheath around nerves that

conduct electrical signals.

Multiple sclerosis attacks the nervous system, causing paralysis and

sometimes blindness.

Until the age of two, children cough and sneeze their way through

common viral infections. The hygiene hypothesis suggests that

exposure to infections passed from younger brothers and sisters may

help to develop the immune system of older children.

Researchers set out to test the hypothesis by comparing 136 adults in

Tasmania who have multiple sclerosis with 272 people who don't. They

were all interviewed about their childhood environment.

In the Jan. 26 issue of the Journal of the American Medical

Association, the investigators report those who had up to five years

of contact with a younger brother or sister had an 88 per cent

reduced risk of suffering MS.

Among adults who lived with a young sibling for one to three years, a

43 per cent reduced risk was observed.

People who were exposed to a younger sibling for longer seemed to

have a lower risk of developing mononucleosis or an overactive

reaction to Epstein-Barr virus, antibodies from blood tests taken for

the study showed.

If people aren't exposed to the virus until their teens or later, it

tends to cause mononucleosis at least 35 per cent of the time,

according to the U.S. Centers for Disease Control.

Study author Anne-Louise Ponsonby of the Menzies Research Institute

in Hobart, Australia, and her colleagues note their findings need to

be confirmed by further studies.

Cheers, Al Pater.