AIDS In Detail Essay, Research Paper
Acquired immunodeficiency syndrome (AIDS). Today, despite the continuing
production of better antibiotics since the discovery of penicillin, we are
facing an infectious disease against which all these drugs are virtually
powerless. This disease is spreading inexorably, killing more people and more
people each year. AIDS does not know no national boundaries and does not
discriminate by race or sex. It is rampaging not only throughout the United
States, but also through Africa, India, China, Russia, Europe, South America,
and the Caribbean countries. Even infants and children are at risk. AIDS is
similar to the bubonic plague or the "BLACK DEATH" that killed perhaps
one-third in Europe in the 14th century. Yet, the difference from the
"Black Death" and AIDS is that it is in slow motion because the
infectious agent that causes AIDS can remain dormant in a person’s body for
several years before it causes illness, and because death from AIDS can be slow
and drawn out once symptoms appear. AIDS is essentially a disease of the immune
system. The body’s defenses are destroyed and the patient becomes prey to the
infections and cancers that would normally be fought off without any trouble. In
1984 it was proved that AIDS is caused by the human immunodeficiency virus
(HIV). A virus is a minute infectious particle that enters and kills the immune
cells, or lymphocytes. Because it destroys the very mechanism humans rely on for
protection, prior to 1996 contracting Aids was considered a death sentence. For
many years, 85 to 90 percent of all AIDS patients died within three years. They
might have recovered from one infection only to succumb to another a few months
later. Between infections they remain weak, emaciated and unable to work or
carry on normal activities. In late 1996, almost 15 years after the first
reported AIDS cases, researchers made the discovery that a certain combination
of newly developed drugs could substantially prolong life in some AIDS patients.
But AIDS is a fiendish virus. When researchers cleared it out of a patient’s
bloodstream, it hid in the lymph nodes. Scientists, figured out how to banish it
from the lymph nodes, they found the virus lurking in the brain. Although, there
is hope for a cure because they have done some experiments isolating a gene and
it has had good results in some people infected with AIDS. The area that many
people are concerned is with Southeast Asia-particularly India. At 900 million,
India’s population is almost double that sub-Saharan Africa, which, with 13.3
million HIV-positive adults, accounts for 60 percent of the world’s total adult
infections. The major reasons for such spread in India and following Africa is
the high rate of their population, poverty rate, and other risk factors all
point to a likely explosion. The number of HIV infections worldwide doubled
between 1991 and 1996-and that number is expected to double again by the year
2000. By the turn of the century, about 44 million people will have fallen
victim to the virus that causes AIDS. The signs of hope do not stop by the
reason of Prevention Programs which they have succeeded in reducing
HIV-infection rates dramatically among young men in Thailand and young women in
Uganda-two of the countries hit hardest by the3 disease. The rate of new
infections have also dropped sharply among gay men in the United States,
Australia, Canada, and western Europe. However, many ingredients of the AIDS
epidemic are still mystery. The cause of AIDS remained uncertain for several
years after its discovery. Even now, there are questions about how efficiently
the AIDS virus spreads, whether it will kill everyone who gets it, and why the
virus is do devastating to the immune system. It’s initial spread was in the
United States was among groups that are frowned upon by society-homosexuals and
intravenous(drug users)- AIDS has a stigma associated with it. This makes the
disease difficult to confront rationally. However, people are terrified even by
the word of AIDS. The virus does not get transmitted by any body contact neither
through the air. However, the disease does not pass from one person to another
through the air, by sneezing, on eating utensils, by shaking hands, or through
body contact in sports. There are only four ways it can be spread: through
injection with a needle contaminated with HIV, which it can happen when drug
addicts share needles; by receiving a transfusion of contaminated blood; or-in
the case of infant with an HIV-positive mother-having the virus transmitted
through the placenta before birth, or the mother’s milk after birth. For years,
some people to refused to admit AIDS was a problem. Although, the disease first
received national attention in 1982, when the Centers of Disease Control (CDC)
noticed an alarming rate of rare cancer (Kaposi’s sarcoma) in otherwise healthy
gay men. SOUNDING THE FIRST ALARM Three patients examined by Dr.Gottlieb were
very ill. Interestingly, they had several striking features in common. All had
unusual infections such as thrush, which is the growth in the throat of a fungus
called Candida; or a rare type of pneumonia caused by a parasite called
Pneumocystis. Also, they had been infected by less-common viruses, such as
Epstein-Barr virus, which causes mononucleosis, or by cytomegalovirus (CMV).
Taken together, the infections pointed to a serious defect in the patients’
immune systems. Sure enough, when Dr. Gottlieb drew a vial blood from each
patient and measured special kind of immune cell called a T-helper lymphocyte,
all three patients’ tests gave the same startling result. They were virtually
devoid of T-helper cells, Dr. Gottlieb found. It was clear that they had
seriously deficient immune systems. The three men had something else in common:
they were all homosexuals. At that time it was not clear that the patients’
homosexuality was related to the illness; a patients’ sexual preference had
never before been considered the determining factor of a medical disorder. That
situation was about to change radically. SIGNS AND SYMPTOMS OF AIDS Early
symptoms of HIV, lasting between one and four weeks, can mimic that of
mononucleosis, with symptoms such as swellings of the lymph nodes, headache,
fever, loss of appetite, weight loss, sweating and sore throat. Often of these
symptoms are mistaken for the flu or another viral-type infection, so people may
not even be aware that they have been infected with HIV. Even if the patient has
seen a doctor, the physician may dismiss the symptoms as a viral infection. In
nearly all the cases, this stage dissipates due to the healthy immune system’s
ability to fight the initial infection. Early symptoms may include: *Herpes
zoster (shingles), a skin rash that appear on the chest, abdomen, and/or back.
*Herpes simplex, a common sexually transmits disease that affects the rectal,
genital, esophageal regions of the body. Painful lesions can erupt into
ulceration’s of the area. In HIV/AIDS patients, this may become a chronic
condition. *Thrush, a white coating on the walls of the mouth, gums, and on the
tongue, that is caused by a fungus called Candida Albicans. *Excessive bruising
and bleeding that occurs when a person develops antibodies which attack the
body’s platelets-cells which help blood to clot. This condition can go
unnoticed, and is often not detected until a routine blood test is performed.
*Chronic or intermittent diarrhea, found both in early and late stages of HIV
infection. As the immune system becomes increasingly compromised, the body is
not able to fight off more serious infections that a normal intact immune system
could suppress. Some of these life threatening infection include: *Pneumocystis
pneumonia (PCP), caused by parasite called pneumoncytis carinii. Symptoms
include fever and respiratory complications that often lead to death. *Kaposi’s
sarcoma, a condition in which tumors of the blood vessels develop on the skin,
in the gastrointestinal tract, mouth, lungs, groin, brain liver, and lymph
glands. The mall, nonpainful lesions usually are a red, brown, or purple color.
*Tuberculosis (TB), which can occur in both early and late stages of HIV.
Symptoms include night sweats, fever, cough, and weight loss. One of the major
problems with this aspect of the disease is the development of TB strains
resistant to drugs, making it harder and harder to treat. *Mycobacterium avium
complex, which produces fatigue, chills, night sweats, fever, weight loss,
diarrhea, and abdominal pain. *HIV related lymphoma, swollen lymph glands in the
neck, groin region, or under the arms. This requires radiation and chemotherapy
treatment. *Toxoplasmosis encephalitis, caused by a parasite, which produces an
infection in the brain leading to neuro logical impairment and seizures.
Symptoms include headaches, fever, lethargy, confusion, and loss of balance or
coordination. *Cytomegalovirus (CMV) infection, a viral infection distributed to
all parts of the body through bloodstream and causing infections in the eyes,
lungs, and other organs. About 90 percent of AIDS patients eventually develop
cytomegalovirus. *Crytococcosis. Produced by a fungus found in the soil. This
causes a brain infection. Symptoms include fatigue, fever, nausea and vomiting,
altered mental state, memory loss, confusion, and behavioral changes. *Crytosporidosis,
an infection developed drinking and contaminated water, produces severe diarrhea
and weight loss. KAPOSI’S SARCOMA If the infectious disease specialists were
puzzled, several New York dermatologist were even more perplexed. These doctors,
who specialize in skin diseases, were seeing a number of patients with an
extremely rare kind of cancer called Kaposi’s sarcoma spot on the skin, further
examination reveals the presence of the cancer in an internal organ, such as the
stomach, as well. Kaposi’s sarcoma had been a disease of elderly men in the
Mediterranean origin; in New York City it began to appear in young men of every
ethnic background. It had been known as a slow-growing cancer that could be
treated successfully; in these new, young patients the sarcoma was spreading
fast and damaging internal organs. A cancer of the skin and internal organs does
not sound like it would be related to rare infections of the lung and the brain.
But there is a strong connection-the immune system. It is one of the principles
of the science of immunology that immune cells are essential in protecting the
body from tumor cells. If a small colony of cancers, a tumor, become
established, lymphocytes (part of the immune system) are supposed to find it and
destroy it before it can grow. So Kaposi’s sarcoma in these young gay men could
be seen as opportunistic cancer, taking advantage of the breakdown in the
patients’ defenses, just as the infectious organisms were doing. There was also
a more concrete reason for the doctors to know that the cases of Kaposi’s
sarcoma in young gay men signaled a breach of these person’s protective
mechanisms: Kaposi’s is relatively common in patients whose immune systems were
surprised by medical treatment. Patients taking drugs that suppress the immune
system are also prone to lymphoma, or cancer of the immune system, Soon this
cancer started showing in gay men, too. WHY HOMOSEXUALS? Dr. Currant’s statement
implied two things. One, that there was an infectious organism underlying the
unusual diseases (perhaps an infectious organism that attacked the immune
system). Two, that the homosexual lifestyle was somehow unique. It would be
three years before the suspicion of an infectious agent that attacked immune
cells was verified by the isolation of the AIDS virus. But it was already known
that gay men’s sexual habits differed from those of the most heterosexuals. They
found that two other diseases were very common in homosexual men and that are
sexually transmitted-hepatitis B and gonorrhea. The first thought was that the
occurrence of the Pneumocystis pneumonia and Kaposi’s sarcoma in homosexual men
might involve sexual transmission. The men with Kaposi’s reported having an
average of 61 different partners in the previous year; the public clinic
patients and the men from private physicians said they had had 25 different
sexual partners in the past year. Both of these numbers are much higher than the
two to five sexual partners per year common among nonmonogamous (sexually active
with more than one partner)heterosexuals. The ill men reported contacting a much
higher percentage of their partners in "gay baths", public places
where gay men can go for anonymous sex. The men with Kaposi’s had met with half
of their partners in the baths; the clinic patients had made one-fourth of their
sexual contacts in the baths; and the healthy private patients averaged only one
anonymous partner per year. Homosexual men have higher rates of sexually
transmits diseases than heterosexual men and women because gay men tend to have
larger numbers of different sexual partners, more often engage in furtive
(anonymous) sexual activities, and more frequently have anal intercourse.
PUZZLING SYMPTOMS Any theory of the new disease also had to account for a
puzzling factor: the variety of symptoms seen in AIDS patients before they
entered the final phase of complete susceptibility to opportunistic infections
and cancers. Interviews with AIDS patients revealed many had been very sick for
up to a year before they developed their first case of Pneumocystis pneumonia or
showed their first Kaposi’s spot, both signs of AIDS. One form of illness that
preceded outright AIDS was a state called lymphadenopathy syndrome, or as LAS,
in which the patient had several swollen lymph nodes for three months or more.
These swollen lymph nodes might be in the neck, in the throat, or under the
armpits. Swollen lymph nodes are a sign that the immune system is fighting an
infection. Did any patients with swollen lymph nodes get better, indicating a
successful fight? Or was the struggle always futile? Several physicians
recruited patients with LAS and examined them every few months to learn the
answer. A more serious condition was AIDS-related complex (ARC), a stage of the
illness no longer considered separately. It had been defined in 1983 as the
presence of two or more unexplained clinical symptoms of AIDS and at least two
abnormal lab tests for the related signs. Patients with ARC might lose a large
amount of weight, have frequent fevers, sweat a lot at night, feel very
fatigued, and suffer untreatable diarrhea. It seemed that the presence of ARC
signaled that outright AIDS was inevitable. But what phase of the AIDS disease
process did ARC represent? The Center for Disease Control never officially
recognized ARC for it’s reporting purposes, but the term was useful in
describing what appeared to be on the set of AIDS. Better terminology has
followed from medical advances, however, and the symptoms of what was called ARC
are viewed as just another of the AIDS-related illness rather than as a distinct
stage of the disease. INTRAVENOUS DRUG USERS Heroin addicts have an illegal
habit and are dedicated primarily to getting their next fit. Many do not stay in
one place long enough to be studied. Most of them would rather use their money
for drugs than for medical care, so they do not often enter the traditional
medical system. Hence, relatively, little is known about the medical condition
of those who populate the drug culture. Striking a needle into your vein after
someone else has used it is an easy way to get any infectious diseases that the
other person may have. It is like giving yourself a transfusion of infected
blood. That is why IV drug users have a high rate of hepatitis, a blood disease
that is lethal if left untreated. That is why they become the second group among
whom AIDS rapidly spread. Within a year of the onset of the epidemic, almost 20%
of AIDS patients were found to be IV drug users. But most IV drug users are
heterosexuals. Many female addicts resort to prostitution to support their
habit. An infected prostitute can spread AIDS to any of her customers, and those
men can spread it to any women or men they later have sex with. Former addicts
can also transmit AIDS to any person they have a sexual relationship with, if
they acquired the AIDS infection while they are using drugs. From these
mysterious and frightening beginnings among gay men and IV drug users, AIDS was
about to show its versatility by appearing in several new population groups.
Indeed, epidemiologists were anticipating this development. If the new syndrome
could be spread by sex between two men, they asked themselves, might it also be
transmitted by sex between a man and a woman? And if it could be spread by blood
on contaminated needles used by heroin addicts, could it be spread by blood used
for medical purposes, such as during surgery? The answers to both questions
turned out to be affirmative. Between the end of 1981 and the end 1982, several
new groups were rapidly identified who were at greatly increased risk for
contracting AIDS. They were as follows: *Women who had sex with men who had the
AIDS infection. *Babies born to women infected with the AIDS virus.
*Hemophiliacs who injected blood products containing a clotting factor. *Surgery
patients who were transfused with contaminated blood. *Newly arrived immigrants
from Haiti and their sexual contacts. In each instance, transmission was either
sexual contact or through receiving infected blood. It is essential to recognize
that as each risk group was identified, it fit one of these patterns of
transmission. There was no group of unexplained AIDS cases that could have been
spread by casual contact, such as being sneezed on by person with AIDS or eating
food prepared by a person with AIDS. From May 1981 to the present, all evidence
has confirmed that AIDS is spread only by intimate contact, not by the
day-to-day, public encounters we all have in our business and social lives. But
with the regard of the two ways that AIDS is transmitted, blood and sex, it is
clear the illness does not select particular groups to afflict. It does not
matter if you whether you are a man or women, or what type of lifestyle you
practice. If you are injected or transfused with contagious blood or take into
your body other contagious bodily fluids, such as vaginal secretions or semen,
you run a high risk of getting AIDS. Minute amounts of these fluids pose very
little threat to transmitting the virus, and most nongenital fluids, such as
saliva, are currently thought to pose no risk whatsoever of transmitting it.
There is, however, a theoretical risk involved when any fluid is passed from an
infected person, though the relative risk is extremely small. Research is still
being done to prove these conjecture. 80 percent of babies HIV positive did not
develop AIDS although, their mother had AIDS. HEMOPHILIACS There are several
diseases in which the blood does not clot properly. Those born with these
conditions lack one of the many elements in the blood that are essential to stop
bleeding. Hemophilia A is an inherited clotting disorder that afflicts men
almost exclusively. In a person with severe hemophilia A, internal bleeding or
bleeding into joints can lead to serious complication, possibly even death. Even
small cuts clot slowly. It was persons with severe hemophilia A who were at
highest risk to get AIDS. To control their bleeding tendency, hemophiliacs
inject themselves with a concentrated preparation made from the blood of persons
with normal clotting ability. This preparation, called Factor VIII, is credited
with increasing the life expectancy of hemophiliacs in the last two decades from
35 to 55 years old. Some hemophiliacs have a mild disorder and use Factor VIII
only when they actually have a bleeding episode. But all hemophiliacs depend on
it at some point. Factor VIII, which was life saving for hemophiliacs, suddenly
turned to be an instrument of death. The preparation is made by pooling blood
collected from 2,000 to 5,000donors, then concentrating it, quick-drying it, and
putting it in vials. Because so many people’s blood was represented in each vial
of Factor VIII, the possibility existed that at least one donor had AIDS or was
harboring the AIDS organism-especially because drug users (until concerns were
raised about infected donors) often sold their blood for cash. And because each
hemophiliac uses 20, 30, or 40 vials of Factor VIIII each year, there was a good
chance that he would encounter a contaminated vial sooner or later. IDENTIFYING
THE VIRUS In particular, no known infectious agent was capable of producing the
specific destruction of the immune system that AIDS causes. Underlying all the
symptoms of AIDS is one primary defect: loss of a pivotal type of white blood
cells called the T4 helper lymphocyte(The role of T4 lymphocytes is to help
other types of immune cells become active and do their job. Without the T4
helper cells, the immune system virtually shuts down. And in some AIDS patients
there was an almost complete loss of T4 helper cells. Viruses are the most
minute form of life. Some people would not even call viruses living organisms.
They are many times smaller than bacteria, the other cause of human infectious
disease. Whereas bacteria are independent, able to grow and reproduce outside
cells of the organism they infect, viruses are parasites. In order to make more
of their kind, viruses must enter the cells of the creature they infect and take
over the cellular machinery. They subvert its productive power by making more of
their own kind. The cell dies, but the virus thrives. The virus is an
intracellular parasite because it’s structure, unlike that of a bacterium, is
too rudimentary to sustain itself-it must live within another cell (Bacteria are
internally complex, containing all the equipment necessary for life). Viruses
contain only the genetic material necessary to propagate themselves and a
tightly wrapped protective coat of proteins. These differences lead to a crucial
medical distinction between bacteria and viruses. Twentieth-century medical
science has developed many antibiotics drugs, such as penicillin, to combat
bacterial infections. But viruses are more difficult to kill. Because they
reproduce inside of our own cells, it is difficult to find a drug to stop the
virus from reproducing without harming the host cell. Progress against diseases
caused by viruses-such as small pox, mumps, measles, and polio-has come through
vaccines, which prevent infections. Latency, means that the infection stays in a
person’s body for a while before it causes clinical illness. Because viruses can
lie dormant inside cells, they can have long latency periods. The latency
periods for AIDS-the time between exposure to the infection and the first
symptoms-may be as long as eight years, but it is usually three to five years.
In children the latency is much shorter, and in women it may be shorter than in
men. Persistence refers to how long the infectious agent remains after it starts
the disease. With AIDS it is most likely that the agent stays for the person’s
remaining lifetime. Despite treatment of each opportunistic infection, the
immune system remains impaired. As fast as new immune cells are made they are
destroyed. One tentative conclusion is that a viral ancestor of HIV evolved in
Africa millions of years ago and affected monkeys. Gradually it changed to the
form of HIV we see today. But this still does not explain why the virus suddenly
started causing human disease in the last quarter of the 20th century. THE
OFFICIAL U.S. DEFINITION OF AIDS There are two factors which determine the
category: T-cell count and history of disease of symptoms. The T-cell
(officially called CD4lymphocyte) is the vulnerable immune system cell the HIV
virus attacks, then uses as a breeding ground. Eventually, the T-cells killed by
the virus. As a person’s T-cell count decreases, the risk of severe disease, or
"opportunistic illness", increases. The three official levels of
T-cell counts are: Level 1: a T-cell count greater than 500cells/ml Level 2: a
T-cell count between 200-499 cells/ml Level 3: a T-cell count less than 200
cells/ml These categories are based on the lowest T-cell count registered by a
person. For example, someone who once tested at 180 but later received a boost
in T-cells from a new protease inhibitor would still be considered level 3. To
determine the three official government classifications, symptoms are also a
factor. For example, a patient is in AIDS category 1 if he or she is
asynmptomatic (no symptoms) and has a level 1 T-cell count. An AIDS category 2
patient has a level 2 T-cell count and at least one of the early stage illness
but has not developed a later-stage disease, such as pneumonia or Kaposi’s
sarcoma. In category 3-full-blown AIDS-the T-cell count has dropped below 200
and the patient has developed a later-stage disease. TREATMENT BREAKTHROUGHS
There have been so many attempts to find a solution to end with AIDS but it’s
too complex and we know little of it, therefore it’s difficult to find a
solution. Although, many experiments have been made for example the cocktail.
It’s a treatment of vaccines that combine with an AZT. However, this vaccines
does work for some but for others it does not do anything. Yet, the newest
discovery is that some people are born with a certain type of gene that does not
develop AIDS but has the virus. So this person may pass on the Virus and have it
himself but it will not affect him at all.
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