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HIV and AIDS
HIV (human immunodeficiency virus)
is the virus that causes AIDS. This virus may be passed
from one person to another when infected blood, semen,
or vaginal secretions come in contact with an uninfected
person’s broken skin or mucous membranes. A mucous
membrane is wet, thin tissue found in certain openings
to the human body. These can include the mouth, eyes,
nose, vagina, rectum, and opening of the penis).
People with HIV have what is called
HIV infection. Some of these people will develop
AIDS as a result of their HIV infection.
What is AIDS?
AIDS stands for Acquired Immunodeficiency
Acquired – means that the disease is not hereditary
but develops after birth from contact with a disease
causing agent (in this case, HIV).
Immunodeficiency – means that the disease
is characterized by a weakening of the immune system.
Syndrome – refers to a group of symptoms that
collectively indicate or characterize a disease. In
the case of AIDS this can include the development of
certain infections and/or cancers, as well as a decrease
in the number of certain cells in a person’s
A diagnosis of AIDS is made by a physician
using specific clinical or laboratory standards.
What causes AIDS?
AIDS is caused by infection with a virus called human
immunodeficiency virus (HIV). This virus is passed
from one person to another through blood-to-blood and
sexual contact. In addition, infected pregnant women
can pass HIV to their babies during pregnancy or delivery,
as well as through breast feeding. People with HIV
have what is called HIV infection. Some of these people
will develop AIDS as a result of their HIV infection.
What are the symptoms of HIV?
The only way to know if you are infected is to be tested
for HIV infection. You cannot rely on symptoms to know
whether or not you are infected with HIV. Many people
who are infected with HIV do not have any symptoms
at all for many years.
The following may be warning signs of infection with
- rapid weight loss
- dry cough
- recurring fever or profuse night sweats
and unexplained fatigue
- swollen lymph glands in
the armpits, groin, or neck
- diarrhea that lasts
for more than a week
- white spots or unusual blemishes
on the tongue, in the mouth, or in the throat
- red, brown, pink, or purplish blotches
on or under the skin or inside the
- memory loss, depression,
and other neurological disorders
However, no one should assume they are infected if
they have any of these symptoms. Each of these symptoms
can be related to other illnesses. Again, the only
way to determine whether you are infected is to be
tested for HIV infection.
Similarly, you cannot rely on symptoms to establish
that a person has AIDS. The symptoms of AIDS are similar
to the symptoms of many other illnesses. AIDS is a
medical diagnosis made by a doctor based on specific
criteria established by the CDC.
How does HIV cause AIDS?
HIV destroys a certain kind of blood cell (CD4+ T cells) which is crucial to
the normal function of the human immune system. In fact, loss of these cells
in people with HIV is an extremely powerful predictor of the development of AIDS.
Studies of thousands of people have revealed that most people infected with HIV
carry the virus for years before enough damage is done to the immune system for
AIDS to develop. However, sensitive tests have shown a strong connection between
the amount of HIV in the blood and the decline in CD4+ T cells and the development
of AIDS. Reducing the amount of virus in the body with anti-retroviral therapies
can dramatically slow the destruction of a person’s immune system.
long does it take for HIV to cause AIDS?
Prior to 1996, scientists estimated that about half
the people with HIV would develop AIDS within 10 years
after becoming infected. This time varied greatly from
person to person and depended on many factors, including
a person's health status and their health-related behaviors.
Since 1996, the introduction of powerful anti-retroviral
therapies has dramatically changed the progression
time between HIV infection and the development of AIDS.
There are also other medical treatments that can prevent
or cure some of the illnesses associated with AIDS,
though the treatments do not cure AIDS itself. Because
of these advances in drug therapies and other medical
treatments, estimates of how many people will develop
AIDS and how soon are being recalculated, revised,
or are currently under study.
As with other diseases, early detection of infection
allows for more options for treatment and preventative
What body fluids transmit HIV?
These body fluids have been proven to spread HIV:
- vaginal fluid
- breast milk
- other body fluids containing blood
These are additional body fluids that may transmit
the virus that health care workers may come into contact
- fluid surrounding the brain and the spinal cord
- fluid surrounding bone joints
- fluid surrounding
an unborn baby
Can I get HIV from kissing?
On the Cheek:
HIV is not transmitted casually, so
kissing on the cheek is very safe. Even if the other
person has the
virus, your unbroken skin is a good barrier. No one
has become infected from such ordinary social contact
as dry kisses, hugs, and handshakes.
Open-mouth kissing is considered
a very low-risk activity for the transmission of
HIV. However, prolonged open-mouth
kissing could damage the mouth or lips and allow
HIV to pass from an infected person to a partner
enter the body through cuts or sores in the mouth.
Because of this possible risk, the CDC recommends
against open-mouth kissing with an infected partner.
One case suggests that a woman became infected with
HIV from her sex partner through exposure to contaminated
blood during open-mouth kissing.
Can I get HIV from oral sex?
Yes, it is possible for either partner to become infected
with HIV through performing or receiving oral sex.
There have been a few cases of HIV transmission from
performing oral sex on a person infected with HIV.
While no one knows exactly what the degree of risk
is, evidence suggests that the risk is less than that
of unprotected anal or vaginal sex.
If the person performing oral sex has HIV, blood from
their mouth may enter the body of the person receiving
oral sex through
- the lining of the urethra (the opening at the tip
of the penis);
- the lining of the vagina or cervix;
- the lining
of the anus; or
- directly into the body through
small cuts or open sores.
If the person receiving oral sex has HIV, their blood,
semen (cum), pre-seminal fluid (pre-cum), or vaginal
fluid may contain the virus. Cells lining the mouth
of the person performing oral sex may allow HIV to
enter their body.
The risk of HIV transmission increases:
- if the person
performing oral sex has cuts or sores around
or in their mouth or throat;
- if the person receiving
oral sex ejaculates in the
mouth of the person performing oral sex; or
- if the person receiving oral sex has another sexually
transmitted disease (STD).
Not having (abstaining
from) sex is the most effective way to avoid HIV.
Some people say
HIV doesn't cause AIDS. What are the facts?
The epidemic of HIV and AIDS has attracted
much attention both within and outside the
communities. Much of this attention comes from the
many social issues related to this disease such as
sexuality, drug use, and poverty. Although the scientific
evidence is overwhelming and compelling that HIV
is the cause of AIDS, the disease process is
completely understood. This incomplete understanding
has led some persons to make statements that AIDS
is not caused by an infectious agent or is
caused by a
virus that is not HIV. This is not only misleading,
but may have dangerous consequences. Before the discovery
of HIV, evidence from epidemiologic studies involving
tracing of patients’ sex partners and cases
occurring in persons receiving transfusions of blood
clotting products had clearly indicated that the
underlying cause of the condition was an infectious
with HIV has been the sole common factor shared by
AIDS cases throughout the world among men who have
sex with men, transfusion recipients, persons with
hemophilia, sex partners of infected persons, children
born to infected women, and occupationally exposed
health care workers.
The conclusion after more than 20 years of scientific
research is that people, if exposed to HIV through
sexual contact or injecting drug use for example, may
become infected with HIV. If they become infected,
most will eventually develop AIDS.
HIV can be detected in virtually everyone who has
STD Information Center | HIV/AIDS
If you think you may have a sexually
transmitted disease, you should see a physician immediately
to be properly diagnosed and treated. You should
not try to diagnose or treat symptoms on your own.