There is a well known axiom that the squeaky wheel gets the grease. This
is the case here. AIDS activists have made such a big issue out of it
that it has gained a lot of notoriety. The fact that AIDS has become
Hollywood chic hasn't hurt either.

Although it is a communicable disease, medically speaking AIDS IS 100%
PREVENTABLE.  First of all, it is more difficult to get AIDS than
originally thought. There must be an exchange of body fluids. Barring
open wounds/sores you cannot get aids from someone by hugging them. Nor
can you get it by someone spitting on you (unless you lick it off). And
you definitely cannot get it from toilet seats. The main vectors of the
AIDS virus are multiple sex partners and shared needles. If you are
monogamous and don't do drugs you are almost 100% safe from AIDS.

Also, technically speaking, you don't die from AIDS either. AIDS strips
your immune system of its ability to protect you from a variety of fatal
diseases. It is these diseases that kill you, not the AIDS virus.
Admitidly, this is a fine distinction to someone dying from the effects of
AIDS.

Related subject: Have you ever wondered what happened to those
self-administered AIDS testing kits? If you were my student you would know
that plus everything there is to know about Parkinson's Disease with no
increase in tuition.

In medical tests there are two factors that affect the accuracy:
sensitivity and selecticity (also called specificity). Sensitivity refers
to how well a test detects the presence of a disease. A test that detects
95 occurences of a condition out of 100 has a sensitivity of 95%. In
practical terms this means that 5% of the people who have the condition
will test negative for it, known as a False Negative.

Selectivity (specificity) refers to a test's ability to detect only that
specific condition and none other. A test that indicates the presence of
the condition 5 times when administered to 100 people without the
condition has a selectivity of 95%. This means that 5% of the  people who
do not have the condition will test positive, known as a False Positive.
Most advertisements give only one number for the "accuracy" of a test.
This is usually either the sensitivity or an avereage of the two.

Now let's consider the Little Stiverson Beer Can Rejuvinator and AIDS
Testing Kit with an advertised "accuracy" of 99.9%. Let us assume this is
the figure for both selectivity and sensitivity. Let us further assume
that this test is administered to every citizen in the USA. This would
give us a population base of about 300 million people. Since the number of
citizens with AIDS is less than 1 million we will consider this population
to be AIDS free for the purposes of this demonstation.

If a test that is 99.9% sensitive is administed to 300 million people
without the condition, .001 * 300,000,000 = 300,000 of them will test
positive even though they do not have the disease.

Now tell me, what business will risk the chance of 300,000 lawsuits when,
after years of worry and expence, those people find out they did not realy
have the disease? In fact, the actual figures are much higher than that.
The AIDS test used by the Red Cross to test donated blood had 10 FALSE
POSITIVES for every single TRUE POSITIVE! That is why they stopped testing
for AIDS. This would also be a good argument against the true validity of
drug testing in the workplace.

Just thought I would throw this in at no extra charge. (So I gave my three
cents worth instead of two cents!)

Bruce
57/9
Sinemet, Mirapex & Tazmar

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Healthcare Informatics  Lab |  a mistake the next time we make it."
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