HPAVC/HPAVC CD-ROM.iso/pc/HOMEWORK.ZIP/770.TXT

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This file is copyright of Jens Schriver (c)
It originates from the Evil House of Cheat
       More essays can always be found at:
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Essay Name       : 770.txt
Uploader         : Antonio Bernardi
Email Address    :
Language         : english
Subject          : Drugs
Title            : Aids
Grade            : college
School System    : MSU
Country          : USA
Author Comments  : Why isn't this working?
Teacher Comments : A
Date             : 5/8/96
Site found at    : luck
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 AIDS - What's new ?
                         -------------------
  Is the message getting through? We already know enough about AIDS to
prevent its spread, but ignorance, complacency, fear and bigotry continue
to stop many from taking adequate precautions.

  We know enough about how the infection is transmitted to protect
ourselves from it without resorting to such extremes as mandatory testing,
enforced quarantine or total celibacy. But too few people are heeding the
AIDS message. Perhaps many simply don't like or want to believe what they
hear, preferring to think that AIDS "can't happen to them." Experts
repeatedly remind us that infective agents do not discriminate, but can
infect any and everyone. Like other communicable diseases, AIDS can strike
anyone. It is not necessarily confined to a few high-risk groups. We must
all protect ourselves from this infection and teach our children about it
in time to take effective precautions. Given the right measures, no one
need get AIDS.

The pandemic continues:
-----------------------
  Many of us have forgotten about the virulence of widespread epidemics,
such as the 1917/18 influenza pandemic which killed over 21 million people,
including 50,000 Canadians. Having been lulled into false security by
modern antibiotics and vaccines about our ability to conquer infections,
the Western world was ill prepared to cope with the advent of AIDS in 1981.
(Retro- spective studies now put the first reported U.S. case of AIDS as
far back as 1968.) The arrival of a new and lethal virus caught us off
guard. Research suggests that the agent responsible for AIDS probably dates
from the 1950s, with a chance infection of humans by a modified Simian
virus found in African green monkeys. Whatever its origins, scientists
surmise that the disease spread from Africa to the Caribbean and Europe,
then to the U.S. Current estimates are that 1.5 to 2 million Americans are
now probably HIV carriers, with higher numbers in Central Africa and parts
of the Caribbean.

Recapping AIDS - the facts:
---------------------------
  AIDS is an insidious, often fatal but less contagious disease than
measles, chicken pox or hepatitis B. AIDS is thought to be caused primarily
by a virus that invades white blood cells (lymphocytes) - especially
T4-lymphocytes or T-helper cells - and certain other body cells, including
the brain. In 1983 and 1984, French and U.S. researchers independently
identified the virus believed to cause AIDS as an unusual type of
slow-acting retrovirus now called "human immunodeficiency virus" or HIV.
Like other viruses, HIV is basically a tiny package of genes. But being a
retrovirus, it has the rare capacity to copy and insert its genes right
into a human cell's own chromo- somes (DNA). Once inside a human host cell
the retrovirus uses its own enzyme, reverse transcriptase, to copy its
genetic code into a DNA molecule which is then incorporated into the host's
DNA. The virus becomes an integral part of the person's body, and is
subject to control mechanisms by which it can be switched "on" or "off".
But the viral DNA may sit hidden and inactive within human cells for years,
until some trigger stimulates it to replicate. Thus HIV may not produce
illness until its genes are "turned on" five, ten, fifteen or perhaps more
years after the initial infection.

  During the latent period, HIV carriers who harbour the virus without any
sign of illness can unknowingly infect others. On average, the dormant
virus seems to be triggered into action three to six years after first
invading human cells. When switched on, viral replication may speed along,
producing new viruses that destroy fresh lymphocytes. As viral replication
spreads, the lymphocyte destruction virtually sabotages the entire immune
system. In essence, HIV viruses do not kill people, they merely render the
immune system defenceless against other "opportunistic: infections, e.g.
yeast invasions, toxoplasmosis, cytomegalovirus and Epstein Barr
infections, massive herpes infections, special forms of pneumonia
(Pneumocystis carinii - the killer in half of all AIDS patients), and
otherwise rare malignant tumours (such as Kaposi's sarcoma.)

Cofactors may play a crucial contributory role:
-----------------------------------------------
  What prompts the dormant viral genes suddenly to burst into action and
start destroying the immune system is one os the central unsolved
challenges about AIDS. Some scientists speculate that HIV replication may
be set off by cofactors or transactivators that stimulate or disturb the
immune system. Such triggers may be genetically determined proteins in
someone's system, or foreign substances from other infecting organisms -
such as syphilis, chlamydia, gonorrhea, HTLV-1 (leukemia), herpes, or CMV
(cytomegalovirus) - which somehow awaken the HIV virus. The assumption is
that once HIV replication gets going, the lymphocyte destruction cripples
the entire immune system. Recent British research suggest that some people
may have a serum protein that helps them resist HIV while others may have
one that makes them genetically more prone to it by facilitating viral
penetration of T-helper cells. Perhaps, says one expert, everybody exposed
to HIV can become infected, but whether or not the infection progresses to
illness depends on multiple immunogenic factors. Some may be lucky enough
to have genes that protect them form AIDS!

Variable period until those infected develop antibodies:
--------------------------------------------------------
  While HIV hides within human cells, the body may produce antibodies, but,
for reasons not fully understood, they don't neutralise all the viruses.
The presence of HIV antibodies thus does not confer immunity to AIDS, nor
prevent HIV transmission. Carriers may be able to infect others. The usual
time taken to test positive for HIV antibodies after exposure averages from
four to six weeks but can take over a year. Most experts agree that within
six months all but 10 per cent of HIV-infected people "seroconvert" and
have detectable antibodies.

  While HIV antibody tests can indicate infection, they are not foolproof.
The ELISA is a good screening test that gives a few "false positives" and
more "false negatives" indicating that someone who is infected has not yet
developed identifiable antibodies.) The more specific Western Blot test,
done to confirm a positive ELISA, is very accurate. However, absence of
antibodies doesn't guarantee freedom form HIV, as someone may be in the
"window period" when, although already infected, they do not yet have
measurable levels of HIV antibodies. A seropositive result does not mean
someone has AIDS; it means (s)he is carrying antibodies, may be infectious
and may develop AIDS at some future time. As to how long seropositive
persons remain infectious, the June 1987 Third International Conference on
AIDS was told to assume "FOR LIFE".

What awaits HIV-carriers who test positive?:
--------------------------------------------
  On this issue of when those who test HIV positive will get AIDS, experts
think that the fast track to AIDS is about two years after HIV infection;
the slow route may be 10, 15, or more years until symptoms appear. Most
specialists agree that it takes at least two years to show AIDS symptoms
after HIV infection, and that within ten years as many as 75 per cent of
those infected may develop AIDS. A report from Atlanta's CDC based on an
analysis of blood collected in San Francisco from 1978 to 1986, showed a
steady increase with time in the rate of AIDS development among
HIV-infected persons - 4 percent within three years; 14 percent after five
years; 36 percent after seven years. The realistic, albeit doomsday view is
that 100 percent of those who test HIV-positive may eventually develop
AIDS.

Still spread primarily by sexual contact:
-----------------------------------------
  AIDS is still predominantly a sexually transmitted disease: The other
main route of HIV infection is via contaminated blood and shared IV
needles. Since the concentration of virus is highest in semen and blood,
the most common transmission route is from man to man via anal intercourse,
or man to woman via vaginal intercourse. Female HIV carriers can infect
male sex partners. Small amounts of HIV have been isolated from urine,
tears, saliva, cereb- rospinal and amniotic fluid and (some claim) breast
milk. But current evidence implicates only semen, blood, vaginal secretions
and possibly breast milk in transmission. Pregnant mothers can pass the
infection to their babies. While breastfeeding is a rare and unproven
transmission route, health officials suggest that seropositive mothers
bottle feed their offspring.

  AIDS is not confined to male homosexuals and the high risk groups: There
are now reports of heterosexual transmission - form IV drug users, hemo-
philiacs or those infected by blood transfusion to sexual partners. There
are a few reported cases of AIDS heterosexually acquired from a single
sexual encounter with a new, unknown mate. And there are three recent
reports of female-to-female (lesbian) transmissions.

Spread of AIDS among drug users alarming:
-----------------------------------------
  In many cities, e.g. New York and Edinburgh, where IV drug use is wide-
spread, IV drug users often share blood-contaminated needles. In New York,
more than 53 percent of drug users are HIV-infected and may transmit the
infection to the heterosexual population by sexual contact and transmission
from mother to child. Studies in Edinburgh, where 51 percent of drug users
are HIV-infected, show that providing clean needles isn't enough to stem
infection. Even given free disposable needles, many drug abusers preferred
the camaraderie of shared equipment. Only with added teaching programs and
free condom offers, are educational efforts likely to pay off. In New
Jersey, offering free treatment coupons plus AIDS education brought 86
percent of local drug users to classes. A San Francisco program issued
pocket-size containers of chlorine bleach to IVDAs with instructions on how
to kill HIV viruses. The Toronto Addiction Research Foundation notes a
similar demand for AIDS information.

Risk of infection via blood transfusion very slight:
----------------------------------------------------
  Infection by blood transfusion is very rare in Canada today. As of
November 1985, the Red Cross, which supplies all blood and blood products
to Canadian hospitals, had routinely tested all blood donations for the HIV
antibody. In 1986, when we last discussed AIDS, the Red Cross reported the
incidence of HIV-positive blood samples as 25 in 100,000. Now, at the start
of 1988, only 10 per 100,000 blood samples are found to be infected -
which, of course, are discarded. Only a tiny fraction of HIV-positive blood
(from HIV-infected people who haven't yet developed detectable antibodies)
can now slip through the Red Cross screening procedure. The minimal risk is
further decreased by screening methods, medical history-taking,
questionnaires and donor inter- views. Very few people at risk of AIDS now
come to give blood. The "self- elimination form", filled out in a private
booth, allows any who feel compelled by peer pressure to donate blood,
total privacy to check the box that says "Do not use my blood for
transfusion."

  As to banking one's own blood, or autologous donations, the Red Cross
permits a few "medically suitable" people, referred by their physician, to
store their blood if they are likely to need blood transfusion in upcoming
elective surgery. They can bank up to four units of blood, taken in the
five weeks before surgery.

  Finally - it can be categorically stated - IT IS ABSOLUTELY IMPOSSIBLE TO
GET AIDS BY GIVING BLOOD!!!

Minimal risk to health care workers:
------------------------------------
  While health care personnel face a slight risk of HIV infection, all
cases reported to date have been due to potentially avoidable mishaps or
failure to follow recommended precautions. Of thousands caring for AIDS
patients worldwide, only a tiny percentage has become infected, and so far
no Canadian health personnel have become HIV-infected. A survey done by the
Federal Centre for AIDS (FCA) of 50 workers occupationally exposed to AIDS
showed that none became infected. A british hospital study on staff looking
after 400 AIDS patients over several years found none who became
HIV-positive. In one U.S. survey, 7 out of 2,500 health care workers
seroconverted and developed HIV antibodies all by potentially avoidable
accidents such as needle pricks, exposure to large amounts of blood, body
fluids spattered into unprotected mouth, eyes or open sores. The reported
mishaps underscore the need for rigorous, vigilant compliance with
preventive guidelines.

Universal body substance precautions (BSP) urged:
-------------------------------------------------
  The newest guidelines suggest that every health care worker, including
dentists, should handle all blood and body fluids as if infectious. Testing
all patients for HIV is not practical and does not confer protection. Rely-
ing on tests that are not 100 per cent accurate would only induce a false
sense of security. Rather than trying to identify infected persons, the CDC
and Ottawa's FCA now promote a philosophy that regards all patients as
potentially infected. (At Johns Hopkins in Baltimore, about six percent of
admissions to the Traumatic Emergency Unit recently tested HIV-positive.)
Hospital and health care workers (including those caring for patients at
home) are encouraged to "think AIDS" and protect themselves. All patients
should be handled in a way that minimizes exposure to blood and body
fluids, e.g. by always wearing gloves when touching open sores, mucous
membranes, taking blood, attending emergencies, putting in IV needles,
touching blood- soiled items, with scrupulous hand-washing between patients
(and whenever gloves are removed), wearing masks, eye protection, plastic
aprons and gowns when appropriate. Taking such precautions will not only
protect against AIDS but also against more infectious agents such as
hepatitis B and some hospital acquired infections. We are all being forced
to remember stringent anti- infection rules!

Absolutely no evidence of spread by casual contact:
---------------------------------------------------
  All the research to date points to the fact that AIDS is not very easy to
catch. One University of Toronto microbiologist speculates that those with
high antibody counts are probably not very infectious. The most infectious
appear to be seemingly healthy persons carrying HIV without any sign of
disease as yet.

  AIDS CANNOT BE PICKED UP CASUALLY via doorknobs, public washrooms, shared
school books, communion coups, cutlery or even by food handlers with open
cuts. A relatively weak virus, HIV is easily killed by a dilute 1 in 10
solution of Javex/bleach, rubbing alcohol and other disinfectants. Even
where parents or caregivers have cleaned up HIV-infected blood, vomit or
feces, HIV has not been transmitted. It is perfectly safe to share a
kitchen, bathroom, schoolroom or workbench with HIV-infected individuals.
But it is inadvisable to share toothbrushes, razors, acupuncture needles,
enema equip- ment or sharp gadgets, which could carry infected blood
through the skin.

  ORDINARY, NONSEXUAL WORKPLACE AND CHILDHOOD ACTIVITIES DON'T TRANSMIT
AIDS. The rare exception might be direct blood-to-blood contact via cuts or
wounds if infected blood (in considerable amounts) spills onto an open
sore. Even in such cases a swab with dilute bleach can kill HIV viruses.

Not spread by mosquitoes and other insects:
-------------------------------------------
  There's no evidence of HIV transmission by insects. Researchers report
that the AIDS virus cannot multiply or survive inside a mosquito. The
infection pattern in Africa - where children who are not sexually active
might be expected to have AIDS if mosquito bites were a real threat - shows
no sign of insect transmission.

Vaccines still a way off:
-------------------------
  Scientists caution that a safe, effective vaccine against HIV may be at
least a decade away, mainly because, like the influenza virus, HIV mutates
(changes structure) quickly, producing different strains. (Several
different HIV strains have already been isolated.) An ideal vaccine must be
able to stimulate neutralization of both "free" viruses and those hidden
within lymphocytes, such as T-helper cells. Researchers in various
countries have developed and are testing a few preliminary vaccines. One
sub-unit vaccine, made from virus coat material (a glycoprotein)
genetically cloned in an insect virus (the baculovirus, which attacks moths
and butterflies but no humans) has been shown to stimulate an immune
response in experimental animals. Another preliminary vaccine, produced by
cloning modified Vaccinia viruses, containing a portion of HIV envelope, is
about to enter clinical trials in New York. (It would be applies, like the
old smallpox vaccine, into a small scratch.) But to date no vaccine tried
in animals or humans has been shown to prevent AIDS.

Testing no solution:
--------------------
  Large scale, screening of the public for HIV antibodies offers little
pro- tection because today's apparent negatives can become infected
tomorrow or test seropositive when antibodies develop in those already
harboring HIV. Reliance on tests could lull people into false complacency.
A "false nega- tive" result may fool someone into risky sexual behaviour.
Curiously, despite a widespread demand for tests, especially among
high-risk groups, a study in Pittsburgh showed that 46 percent of a group
of homosexual/bisexual men tested did not return for or want their antibody
test results. Many health experts therefore believe that mandatory testing
would be useless as HIV antibody tests only indicate exposure, not
necessarily infectivity. As one University of Toronto virologist puts it:
"Widescale compulsory screening for HIV antibodies is not necessarily
useful and will do nothing to promote prevention or cure. What's needed
perhaps is more accurate knowledge about the disease and more responsible
behaviour rather than testing."

  Those who should consider testing might include people known to be at
high risk and any who think they may have been HIV-infected or who wish to
be tested and have discussed it with their physician. What's needed, as
with any infectious disease, is not more testing buy more precautions
against infection.

Message clear but still largely unheeded:
-----------------------------------------
  Despite a veritable blitz of AIDS information, experts claim that too few
people are changing their lifestyles or behaviour sufficiently to protect
themselves from AIDS. A recent Canadian poll revealed widespread ignorance
of the fact that AIDS is primarily a sexually acquired infection, not
caught by casual touch. The survey showed that although sexual intercourse
among adolescents has risen steeply in the past 10 years, less than 25
percent of those aged 18 to 34 have altered their sexual behaviour to
protect them- selves against AIDS, i.e. by consistent use of condoms and
spermicide.

  THE CENTRAL MESSAGE IS CLEAR: UNLESS ABSOLUTELY SURE (and monogamy is no
guarantee) THAT YOUR SEX PARTNER IS HIV-FREE, USE A CONDOM (latex, not made
of animal material) plus a reliable spermicide (e.g. one containing
nonoxyl- 9). Studies with infected haemophiliacs show that condom use by a
regular sex partner reduces infection risks, compared to unprotected sex.
And regular condom use may bring the added reward of preventing other
sexually trans- mitted diseases such as gonorrhea and chlamydia or unwanted
pregnancy.

  Many educators say that, by whatever means, AIDS information must get out
to young people at an early enough age for them to absorb it before
becoming sexually active. Only by acting upon accurate AIDS information can
people protect themselves, their sex partners, families and ultimately
society from this disease.

Protection the only answer:
---------------------------
  The best way to avoid AIDS is to regard it as a highly lethal disease and
practice commonsense prevention. Avoiding infection is IN ONE'S OWN HANDS.
People can protect themselves. To halt its spread, people are encouraged to
obtain and apply accurate AIDS information to their living styles and
sexual habits in order to reduce the risk of getting or transmitting the
virus. Sadly, health promoters claim that "reaching the many who don't want
to know" is no easy task. Health promoters suggest that educators must
learn how and when to communicate AIDS information - in the right way at
"teachable" moments. Many Public Health Departments are now taking the lead
in disseminating education about AIDS with largescale public awareness
programs.

What of the future?:
--------------------
  Many virologists believe that since antibiotics became available in the
late 1940s we have become too complacent about viral infections, no longer
take communicable disease seriously, and have modern medical schools which
devote few teaching hours to anti-infective strategies. In fact, we still
know little about retroviruses such as HIV. Perhaps special virology
research centres, like the Virus Research Institute proposed for the
University of Toronto, will help to halt the tragic toll of AIDS and other
as yet unknown viruses waiting in the wings.


  For more information on AIDS or aid for AIDS call: local AIDS committees,
Public Health Departments, or AIDS Hotlines (in Toronto 392-AIDS.)

=============================================================================

  In everyday conversations, AIDS is usually a source for humour. For
anybody who is suffering from the disease there is very little humour. The
best prevention is not the thought that "IT COULD NEVER HAPPEN TO ME", if
that was so all the insurance companies would be out of business.

  The most reliable person to be put in-charge of preventing you for getting
AIDS is YOURSELF!!!!


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