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Questions
and Answers: HIV is the Cause of AIDS
What is AIDS?
AIDS stands for acquired
immunodeficiency syndrome. A diagnosis of AIDS is made by a physician
using certain 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. Most of these people will develop AIDS as a result
of their HIV infection.
What body fluids transmit
HIV?
These body fluids have been
proven to spread HIV:
- blood
- semen
- 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 with:
- fluid surrounding the brain
and the spinal cord
- fluid surrounding bone
joints
- fluid surrounding an unborn
baby
How does HIV cause
AIDS?
HIV destroys a certain kind
of blood cells--CD4+ T cells (helper cells)--which are 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, recently developed sensitive tests have
shown a strong connection between the amount of HIV in the blood
and the decline in CD4+ T cell numbers and the development of
AIDS. Reducing the amount of virus in the body with anti-HIV
drugs can slow this immune destruction.
An author indicated
in a recently published book that AIDS is caused by HHV-6 rather
than HIV. Is this true?
No, this
is not true. Both HHV-6
and HIV infect the same kind of cells in a person's body. These
cells are called CD4+ T cells (helper cells). However, AIDS will
not develop in someone who is not infected with HIV. Infection
with HHV-6 does not lead to infection with HIV. HHV-6, one of
the eight known human herpes viruses, is common throughout the
world, with over 90% of adults in many populations being infected.
Most people are infected with HHV-6 between the ages of 6 months
and 2 years old, soon after they lose their mother's antibodies.
HHV-6 is
the cause of roseola [ro
ZEE o la], a usually mild childhood disease that is also called
exanthem subitum [eg ZAN them SUBI tum] or sixth disease. Approximately
30% of all children get roseola, usually before 2 years of age.
Why do some people
make statements that HIV does not cause AIDS?
The epidemic of HIV and
AIDS has attracted much attention both within and outside the
medical and scientific communities. Much of this attention comes
from the many social issues--homosexuality, drug use, poverty--related
to this disease. Although the scientific evidence is overwhelming and compelling
that HIV is the cause of AIDS,
the disease process is not yet 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 or blood clotting products had clearly indicated that
the underlying cause of the condition was an infectious agent.
Infection
with HIV has been the sole common factor shared by AIDS cases
throughout the world among
homosexual men, transfusion recipients, persons with hemophilia,
sex partners of infected persons, children born to infected women,
and occupationally exposed health care workers. Recommendations
to prevent HIV involve guidance to avoid or modify behaviors
that pose a risk of transmitting the virus as well as the use
of tests to screen donors of blood and organs.
The inescapable conclusion
of more than 15 years of scientific research is that people,
if exposed to HIV through sexual contact or injecting drug use,
may become infected with HIV. If they become infected, most will
eventually develop AIDS.
How can I get more
information about AIDS?
CDC operates a free telephone
service that is available 24-hour, 7 days a week. You can contact
the CDC National STD and AIDS Hotlines at 1-800-342-2437. Service
for Spanish-speaking audiences and the Deaf are also available. |
