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What
is HIV/AIDS?
HIV is the abbreviation of Human Immuno -
deficiency Virus. This virus causes Acquired Immuno Deficiency
Syndrome (AIDS). Thus HIV is the name of the virus and AIDS is
the name of the disease.
As the name AIDS implies, it is a condition
where there is deficiency in the body's natural defence
mechanism or the immune system. It is "acquired"
because it is not a hereditary condition. AIDS is acquired due
to certain behavioural patterns. Syndrome means a group of
symptoms. When one get AIDS, there can be a wide range of
symptoms, all of which are due to body's diminished ability to
fight diseases.
It is important to note that every person who
has HIV infection will develop, AIDS over a period of time
depending upon the general health and natural defence mechanism
of the body.
How
do people get infected with HIV?
HIV is transmitted mostly through semen and
vaginal fluids during unprotected sex without the use of
condoms. Globally, most cases of sexual transnmission involve
men and women, although, in some developed countries homosexual
activity remains the primary mode. Besides sexual intercourse,
HIV can also be transmitted during drug injection by the sharing
of needles contaminated with infected blood; by the transfusion,
of infected blood or blood products; and from an infected woman
to her baby - before birth, during birth or just after delivery.
How
can I avoid being infected through sex?
You can avoid HIV infection by abstaining
from sex, by having a mutually faithful monogamous sexual
relationship with an uninfected partner or by practicing safer
sex. Safer sex involves the correct use of a condom during each
sexual encounter and also includes non-penetrative sex.
Is
Oral Sex Unsafe?
Oral sex (one person kissing, licking or
sucking the sexual areas of another person) does carry some risk
of infection. If a person sucks the penis of an infected man,
for example, infected fluid could get into the mouth. The virus
could then get into the blood if you have bleeding gums or tiny
sores somewhere in the mouth. The same is true if infected
sexual fluids from a woman get into the mouth of her partner.
But infection from oral sex alone seems to be very rare.
How
does HIV affect the body?
HIV destroys a particular variety of white
blood cells that are essential for destroying disease-causing
germs. There are several varieties of white blood cells in the
body. Of these, lymphocytes form about twenty-five percent of
the total white blood cell count. They normally increase in
number in response to any infection. There are two types of
lymphocytes: (a) B cells and (b) T cells. When the B cells come
in contact with a disease-causing agent such as bacteria or
virus, they secrete large volumes of antibodies - chemical
substances that can destroy the disease-causing germs. The main
functions of B cells are to search identify and then bind with
the disease causing germs.
The T cells are lymphocytes that have
travelled through a small gland called the thymus gland, which
is situated in the middle and upper part of the bony cage of the
chest. When a disease -causing germ enters the body, the T cells
produce several new copies of itself. Each T cell contains
chemical substances that can destroy the specific
disease-causing germs. T cells are also called "killer
cells" because of their two main actions, which are (a)
they secrete chemical substances necessary for destroying the
disease-causing germs and (b) they help the B cells in
destroying the agents
How
does HIV spread in the body?
There are six steps through which the HIV
multiplies and affects the cells. These are illustrated below.
Entry of HIV into cells :
Some cells of the immune system contain a receptor called CD4 on
their surface. CD4 receptor are also found on the T cells. When
the HIV virus enters the body, it first identifies cells with
CD4 and attaches itself to them. Once the HIV binds with the
CD4, the membranes of the virus and the T cell fuse. As a result
of this fusion, the virus RNA, proteins and enzymes enter the T
cell. It is important to remember that although the main target
for HIV is the T cells, it also attaches itself to other types
of white blood cells containing CD4 but does not destroy them.
These cells can act as reservoirs of HIV if the natural defence
mechanism of the body tries to destroy the HIV.
Reverse transcriptase: Once the RNA,
proteins and enzymes of the HIV enter the cytoplasm of the T
cell, an enzyme called, "reverse transcriptase"
present in HIV converts RNA into DNA, which is an abbreviated
form of deoxyribonucleic acid. DNA is a form of ncleic acid that
carries genes, the basic unit of genetic inheritance.
Integration: In this stage, the newly
formed DNA of the HIV enters the T cell's nucleus and is
incorporated into its genes. Thus, when the T cell multiplies,
the virus DNA is also copied. A person infected with HIV may
contain billions of cells containing the HIV DNA.
Transcription: The T cell that
contains HIVDNA cannot produce new viruses unless the RNA is
able to make its own copies. It is important that these RNA are
"read" by the protein-making mechanism of the infected
T cell. To enable production of RNA copies and therefore to
allow multiplication of new viruses, a special type of RNA
called " messenger RNA" is produced. The process of
production of mesenger RNA is called transcription. This process
involves the enzymes of the infected T-cell. The genes of HIV
and the protein-making mechanism of the T cells together control
the process of transcription.
Translation: After the messenger RNA
of the HIV is processed by the nucleus of the infected cell, it
is sent to the cytoplasm. In the cytoplasm, the virus
collaborates with the T cell's protein-making mechanism to make
long chains of proteins and enzymes of HIV. The messenger RNA
acts as a template or guide for production of HIV proteins and
enzymes. The process of making long chains of viral proteins and
enzymes is called translation.
Assembly and budding: In this stage,
the newly made HIV proteins, enzymes and RNA collect just inside
the wall of the infected T cell. At the same time, the proteins
that form the covering of the virus collect within the wall of
the infected T cell. Next, an immature particle of the virus is
formed and it separates from the infected T cell. This new viral
particle has an envelope that includes proteins from the walls
of both, the HIV and the infected T cell. It is important to
remember that the immature virus cannot spread the infection to
other people.
The long chains of proteins and enzymes
formed inside the infected cell are cut into smaller pieces by a
specific enzyme of the virus called protease. This step results
in formation of viral particles that can spread infection to
other T cells.
Are
women at equal risk of getting infected with HIV?
Women are in fact more at risk of getting
infected because of their increased vulnerability. In addition,
their low status within the family and society further heighten
their vulnerability to infection. It is therefore most important
that every woman has access to information about HIV/AIDS to
protect herself.
Does
AIDS affect children?
Yes. Children can be both infected and
affected by AIDS. Over 2.5 million children worldwide are now
infected with HIV. If HIV continues to spread in countries,
there will be a great increase in deaths among infants and
children. It is also estimated that by the year 2000, 10 million
children will have been orphaned as their parents die of AIDS.
How
does a mother transmit HIV to her unborn child?
An HIV-infected mother can infect the child
in her womb through her blood. The baby is more at risk if the
mother has been recently infected or is in a later stage of
AIDS. Transmission can also occur at the time of birth when the
baby is exposed to the mother's blood and to some extent
transmission can occur through breast milk. Transmission from an
infected mother to her baby occurs in about 30% of cases.
Can
HIV be transmitted through breast-feeding?
Yes. The virus has been found in breast milk
in low concentrations and studies have shown that children of
HIV-infected mothers can get HIV infection through breast milk.
Breast milk, however, has many substances in it that protect an
infant's health and the benefits of breast-feeding for both
mother and child are well recognized. The slight risk of an
infant becoming infected with HIV through breast-feeding is
therefore thought to be outweighed by the benefits of
breast-feeding.
Can
blood transfusions transmit HIV infection?
Yes. If the blood contains HIV. In many
places blood is now screened for HIV before it is transfused. If
you need a transfusion, try to ensure that screened blood is
used. You can reduce the chances of needing a blood transfusion
by taking ordinary precautions against serious injury - for
example, by driving carefully, insisting on wearing a seat belt,
and avoiding alcohol.
Can
injections transmit HIV infection?
Yes. If the injecting equipment is
contaminated with blood containing HIV. Avoid injections unless
absolutely necessary. If you must have an injection, make sure
the needle and syringe come straight from a sterile package or
have been sterilized properly; a needle and syringe that has
been cleaned and then boiled for 20 minutes is ready for reuse.
Finally, if you inject drugs, of whatever kind, never use anyone
else's injecting equipment.
What about
having a tattoo or your ears pierced?
Tattooing, ear piercing, acupuncture and some
kinds of dental work all involve instruments that must be
sterile to avoid infection. In general, you should refrain from
any procedure where the skin is pierced, unless absolutely
necessary.
What
about working every day in close physical contact with an
infected person?
There are no risks involved. You may share
the same telephone with other people in your office or work side
by side in a crowded factory with other HIV infected persons,
even share the same cup of tea, but this will not expose you to
the risk of contracting the infection. Being in contact with
dirt and sweat will also not give you the infection.
What
about getting HIV from body fluids like saliva?
Although small amounts of HIV have been found
in body fluids like saliva, feces, urine, and tears, there is no
evidence that HIV can spread through these body fluids.
Can
I get infected with HIV from mosquitoes?
No. From the start of the HIV epidemic there
has been concern about HIV transmission of the virus by biting
and bloodsucking insects, such as mosquitoes. However, studies
conducted by the CDC and elsewhere have shown no evidence of HIV
transmission through mosquitoes or any other insects -- even in
areas where there are many cases of AIDS and large populations
of mosquitoes. Lack of such outbreaks, despite intense efforts
to detect them, supports the conclusion that HIV is not
transmitted by insects.
The results of experiments and observations
of insect biting behavior indicate that when an insect bites a
person, it does not inject its own or a previously bitten
person's or animal's blood into the next person bitten. Rather,
it injects saliva, which acts as a lubricant so the insect can
feed efficiently. Diseases such as yellow fever and malaria are
transmitted through the saliva of specific species of
mosquitoes. However, HIV lives for only a short time inside an
insect and, unlike organisms that are transmitted via insect
bites, HIV does not reproduce (and does not survive) in insects.
Thus, even if the virus enters a mosquito or another insect, the
insect does not become infected and cannot transmit HIV to the
next human it bites.
There also is no reason to fear that a
mosquito or other insect could transmit HIV from one person to
another through HIV-infected blood left on its mouth parts.
Several reasons help explain why this is so. First, infected
people do not have constantly high levels of HIV in their blood
streams. Second, insect mouth parts retain only very small
amounts of blood on their surfaces. Finally, scientists who
study insects have determined that biting insects normally do
not travel from one person to the next immediately after
ingesting blood. Rather, they fly to a resting place to digest
the blood meal.
Can
I get HIV from casual contact (shaking hands, hugging, using a
toilet, drinking from the same glass).
No. HIV is not transmitted by day-to-day
contact in the workplace, schools, or social settings. HIV is
not transmitted through shaking hands, hugging, or a casual
kiss. You cannot become infected from a toilet seat, a drinking
fountain, a door knob, dishes, drinking glasses, food, or pets.
A small number of cases of transmission have
been reported in which a person became infected with HIV as a
result of contact with blood or other body secretions from an
HIV-infected person in the household. Although contact with
blood and other body substances can occur in households,
transmission of HIV is rare in this setting. However, persons
infected with HIV and persons providing home care for those who
are HIV-infected should be fully educated and trained regarding
appropriate infection-control techniques.
HIV is not an airborne or food-borne virus,
and it does not live long outside the body. HIV can be found in
the blood, semen, or vaginal fluid of an infected person. The
three main ways HIV is transmitted are
-
through having sex (anal, vaginal, or
oral) with someone infected with HIV.
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through sharing needles and syringes with
someone who has HIV.
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through exposure (in the case of infants)
to HIV before or during birth, or through breast feeding.
If
a person becomes infected with HIV, does that mean they have
AIDS?
No. HIV is an unusual virus because a person
can be infected with it for many years and yet appear to be
perfectly healthy. But the virus gradually multiplies inside the
body and eventually destroys the body's ability to fight off
illnesses.
It is still not certain that everyone with
HIV infection will get AIDS. It seems likely that most people
with HIV will develop serious problems with their health. But
this may be after many years. Persons with HIV may not know they
are infected but can pass the virus on to other people.
Is
there a vaccine for HIV/AIDS?
While there is currently no vaccine for
HIV/AIDS, research is under way. Many candidate vaccines are
presently undergoing either phase I or phase II clinical trials
in various countries, including Thailand in South-East Asia.
These will be followed by field trials in the community to
determine efficacy, which is a time consuming process and will
take another 3-5 years or more.
Is
there a treatment for HIV/AIDS?
All the currently licensed anti-retroviral
drugs, namely, Zidorudine, Lamirudine, Starudine &
Nevirapine have effects which last only for a limited
duration. In addition, these drugs are very expensive and have
severe adverse reactions while the virus tends to develop
resistance rather quickly with single-drug therapy. The emphasis
is now on giving a combination of drugs including newer drugs
called protease inhibitors; but this makes treatment even more
expensive.
WHO's present policy does not recommend
antiviral drugs but instead advocates strengthening of clinical
management for HIV- associated opportunistic infections such as
tuberculosis and diarrhoea. Better care programmes have been
shown to prolong survival and improve the quality of life of
people living with HIV/AIDS.
How
Can I Tell If I Have HIV Infection?
The only way to know for sure if you have
this virus is by taking a blood test called the "HIV
Antibody Test." Some people call it the "HIV
Test" or the "AIDS Test," even though this test
alone cannot tell you if you have AIDS. The HIV test can tell
you if you have the virus and can pass it to others in the ways
already described. The test is not a part of your regular blood
tests-you have to ask for it by name. It is a very accurate
test.
If your test result is "positive,"
it means you have HIV infection and could benefit from special
medical care. Additional tests can tell you how strong your
immune system is and whether drug therapy is indicated. Some
people stay healthy for a long time with HIV infection, while
others develop serious illness and AIDS more rapidly. Scientists
do not know why people respond in different ways to HIV
infection.
If your test is "negative," and you
have not had any possible risk for HIV for six months prior to
taking the test, it means you do not have HIV infection. You can
stay free of HIV by following prevention guidelines. (In the
past five years, one study indicated that a few people with HIV
infection took longer than six months to test
"positive." This is an extremely rare possibility.)
Less than 2% of all people who test for HIV
get an "inconclusive result." This means this test
cannot determine whether or not they have the virus. Repeat
testing is recommended.
If
I Am HIV Positive, What Should I Do?
If you've tested positive for HIV, consider
the following:
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See a health care professional for a
complete medical work-up for HIV infection and advice on
treatment and health maintainance. Make sure you are tested
for TB and other STDs. For women, this includes a regular
gynecological exam.
-
Inform your sexual partner(s) about their
possible risk for HIV. Your local health department has a
partner notification program that can assist you.
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Protect others from the virus by
following the precautions talked about on this page (for
example, always using condoms and not sharing needles with
others).
-
Protect yourself from any additional
exposure to HIV.
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Avoid drug and alcohol use, practice good
nutrition, and avoid fatigue and stress.
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Seek support from trustworthy friends and
family when possible, and consider getting professional
counseling.
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Find a support group of people who are
going through similar experiences.
Do not donate blood, plasma, semen, body
organs, or other tissue.
What
are the symptoms of the HIV/AIDS?
A person infected with HIV is not likely to
have any symptoms for about three to ten years. This period may
be longer if the natural defense mechanism of the body is good.
Although a person infected with HIV does not have any symptoms,
he/she can spread the infection to others. This is why it is
recommended that any one who has sex with a partner who is not
in mutually faithful relationship should practice safe sex. This
means using a condom correctly for sexual act.
The symptoms of AIDS are divided into major
and minor symptoms. As per the definition of AIDS given by the
World Health Organisation, a person is said to have AIDS if
he/she at least two major signs and at least one minor sign and
there is no other cause of poor immune mechanism. The term
"AIDS related illness" is used when a person has some
of the signs and symptoms, has antibodies to HIV in the blood
but does not have two major and one minor sign.
Major signs:
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Diarrhoea is very common in people with
AIDS. It is normally clear and watery and may be associated
with cramp-like pain in the abdomen and vomiting. Chronic
diarrhea with excessive loss of weight is one of the
important features of AIDS. There may also be,
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Continuous fever and increased sweating
at nights.
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Weight loss by more than 10% in a months
period is also one of the signs.
Minor Signs:
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include chronic cough that does
not respond to routine treatment, enlargement of the lymph
nodes, fungal infection of the mouth called candidiasis,
recurrent infections of herpes group of viruses.
What
are the opportunistic infections in AIDS?
Poor defence mechanism of the body allows
several disease-causing germs to infect people with AIDS. Some
of the common opportunistic infections seen in people with AIDS.
Tuberculosis: This is a bacterial
infection and is normally transmitted when a person with active
tuberculosis coughs or sneezes. During the act of coughing or
sneezing, germ particles of tuberculosis called droplet nuclei
are released in the air. These droplet nuclei contain the
bacterial that cause tuberculosis. When a healthy person inhales
the droplet nuclei, he/she cab get infected with tuberculosis.
Many people in India who are infected with tuberculosis develop
latent infection only. Latent infection means the infected
person will neither have any signs or symptoms nor will be able
to spread the infection to others. They can however, become sick
and get infected with active tuberculosis at a later stage.
Tuberculosis often occurs in the early stages
of HIV infection. Since tuberculosis is already one of the major
health problems in India, people with HIV infection are at a
higher risk of getting it. Very often, tuberculosis is the first
indication that a person has HIV infection. Although
tuberculosis largely affects the lungs,it can affect other
organs of the body also. People with AIDS are more likely to get
infection in other organs of the body.
One of the major concerns related to
tuberculosis and AIDS is resistance of the tuberculosis bacteria
to several medicines that were earlier effective for its
treatment. Resistance of medicines normally occurs when people
fail to complete a course of treatment. Since treatment for
tuberculosis takes several months, there is a very high rate eof
dropouts. People who fail to complete the full course of
treatment can become resistant to medicines and spread the
resistant bacteria to others also. Resistant tuberculosis is one
of the important causes of early death in people with HIV
infection.
Tuberculosis is more common in people with
HIV infection who have less than two hundred CD4+ count. Common
symptoms of tuberculosis include cough, fever, increased
sweating at nights, loss of weight and excessive fatigue.
Diagnostic diseases: Kaposis' sacoma and
cryptococcal meningitis are the two diseases that are a definite
indication of AIDS.
Kaposis's sarcoma: This is the most common
cancer seen in the people with AIDS. Some studies have indicated
that this cancer is due to infection by one of the herpes groups
of viruses. Some other studies have indicated that it is due to
an abnormality of the production of blood cells. Although more
studies are necessary to identify the cause of kaposis's
sarcoma, its presence is a definite indication of AIDS.
Common symptoms of kaposis's sarcoma include
red or purple raised areas on the skin. They may also be present
in internal organs of the body such as mouth, lymph nodes,
digestive track and lungs. Recent advance in management of
kaposis's sarcoma have increased the chances of complete
recovery.
Cryptococcal meningitis: This infection
is caused by a yeast-like fungus called cryptococcus neoformans
It is found in soil in most parts of the world, especially the
soil that is contaminated with bird droppings. In the early
stages of the infection, the fungus affects the brain and the
lungs. In later stages, it can affect any other part of the
body. Cryptococcal meningitis with CD4 count less than fifty.
Common symptoms of cryptococcal meingitis
include fever, mild headache followed by nausea,vomiting, severe
headache and blurring of vision.
Why
is the AIDS epidemic considered so serious?
AIDS affects people primarily when they are
most productive and leads to premature death thereby severely
affecting the socio-economic structure of whole families,
communities and countries. Besides, AIDS is not curable and
since HIV is transmitted predominantly through sexual contact,
and with sexual practices being essentially a private domain,
these issues are difficult to address.
Where
was AIDS first found?
AIDS was first recognised in the United
States in 1981. However, it is clear that AIDS cases had
occurred in several parts of the world before 1981. Evidence now
suggests that the AIDS epidemic began at roughly the same time
in several parts of the world, including the U.S.A. and Africa.
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