HaCKeRz KrOnIcKLeZ 3/HaCKeRz_KrOnIcKLeZ.iso/anarchy/essays/term/aids-2.txt

Text File | 1996-04-27 | 22KB | 371 lines

                         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!!!!


          T A K E   P R E V E N T I V E   P R E C A U T I O N S ! !


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

Thanks to the University of Toronto Faculty of Medicine for the article.