Can people catch Alzheimer's? Possibility cannot be ruled out

[Obama care ponzi scheme]

‘Seeds’ of brain abnormalities can be passed from person to
person as a result of medical procedures, research suggests

Scientists have uncovered the first clinical evidence that
“seeds” of brain changes associated with Alzheimer’s can be
transmitted from person to person.

What has been discovered?

The first clinical evidence that “seeds” of brain abnormalities
closely associated with Alzheimer’s disease can be transmitted
between people.

Alzheimer’s patients have clumps of sticky material made from
protein fragments, called beta amyloid, in their brains. Similar
deposits can build up on the walls of blood vessels in the
brain. The new evidence raises the possibility that microscopic
amyloid particles can pass from person to person as a result of
medical procedures.

How was the discovery made?

Scientists led by Prof John Collinge, from the Medical Research
Council prion unit in London, were examining the brains of eight
individuals who had died from Creutzfeldt-Jakob Disease (CJD), a
rare and lethal brain condition, after receiving pituitary
growth hormone to treat stunted growth.

The hormone, produced by the pituitary gland, a pea-sized organ
at the base of the brain, was taken from the brains of dead
donors. Unexpectedly, as well as the damage caused by CJD, the
researchers also found clear signs of the beta amyloid
Alzheimer’s hallmark in six of the patients. In four, the
deposits were widespread, and only one patient was completely
amyloid-free.

What does this mean?

How did the beta amyloid get there? The eight patients were aged
36 to 51, very young to show clinical signs of Alzheimer’s. None
had genetic variants associated with early-onset Alzheimer’s.

After careful investigation, the scientists concluded the most
likely explanation was that “seeds” of beta amyloid were passed
to the patients in the growth hormone they were treated with.
There is no evidence that having CJD could somehow trigger
Alzheimer’s, which affects different parts of the brain.

Why the concern now?

There is growing evidence that in rare circumstances it might be
possible to “acquire” Alzheimer’s, or at least the brain changes
associated with it. In animal tests, mice and monkeys injected
with liquified brain material from dead Alzheimer’s patients
have gone on to develop beta amyloid deposits in their brains.
But this has never been shown to occur in humans before.

Does this mean you can catch Alzheimer’s?

No, not in the sense that you can catch a cold. Alzheimer’s is
definitely not contagious. But the possibility cannot be ruled
out that brain changes associated with the disease can be
triggered by seeds spread by some medical procedures.

Did the growth hormone patients have Alzheimer’s?

They did not. But most had a pathology – a physical symptom –
linked to the disease. Whetherthey would have gone on to develop
Alzheimer’s had they lived longer remains an unanswered question.

Could going to the dentist put you at risk?

Almost certainly not. But beta amyloid particles are known to
stick to metal, and are hard to remove even by normal
sterilisation procedures. That means they could conceivably
stick to surgical instruments, including the tooth probes used
by dentists.

This might be relevant to procedures that come in to contact
with nerves, like root canal treatments, say the scientists.
However, the likelihood of Alzheimer’s amyloid being transmitted
in this way is extremely remote.

What is the connection with CJD?

CJD is thought to be transmitted by wrongly-shaped rogue
proteins, called prions. There are three main categories of CJD:
spontaneous, which occurs simply by bad luck with age; familial,
which is due to inherited genes; and acquired, which is
transmitted in some way.

Acquired CJD includes the subtype iatrogenic CJD (iCJD) which is
transmitted through surgical procedures, and variant CJD, which
first appeared in 1996 and is caused by eating prion-
contaminated beef.

Collinge and other experts are now beginning to think that
Alzheimer’s and other neurodegenerative diseases like
Parkinson’s might follow a similar pattern. Some cases might be
sporadic, others familial, and others acquired.

In the case of Alzheimer’s, the transmissible agent would not be
a prion but a beta amyloid particle, or seed. Both prions and
beta amyloid particles are hard to remove from metal.

A number of procedures have been known to transmit iatrogenic
CJD. They include neurosurgery, corneal transplants, the placing
of electrodes into the brain and the use of grafts of dura
mater, a membranous sac surrounding the brain. Similar routes of
transmission may conceivably apply to beta amyloid seeds.

Is growth hormone treatment still dangerous?

People in the UK were treated with pituitary growth hormone
extracted from cadaver brains from 1958 to 1985. This was
stopped when it was realised a high proportion of patients were
contracting CJD.

In total, 1,848 men and women were treated with pituitary growth
hormone, of whom 77 have died from the disease. Today a safe
form of synthetic growth hormone is used to treat stunted growth.

http://www.theguardian.com/society/2015/sep/10/can-people-catch-
alzheimers-possibility-cannot-be-ruled-out