human immunodeficiency virus
is the virus that causes AIDS (acquired immunodeficiency syndrome).
The virus gets its name because it infects and damages part of the
immune system - the body's natural defense system.
Often the only way to know if someone is infected with HIV is
through testing. That's because people who are HIV positive may
not know that they have the virus. Most of the signs that someone
has HIV don't show up until that person has developed
full-blown AIDS. By that point, the person is sicker and the
disease can be harder to treat.
Here are the facts on what's involved in getting tested -
and who should get tested for HIV and why.
Who Is at Risk?
The only known way for HIV to be transmitted from one person to
another is when it is spread through the fluids from an infected
person's body. Thousands of U.S. teens become infected with HIV
When teens in the United States become infected with HIV, it
usually happens in one of two ways:
By sharing needles used to inject drugs or other
(including needles used for injecting steroids, and tattooing and
body art). If the person who has used the needle is infected with
HIV, his or her blood on the needle can infect anyone else who
uses the same needle.
Through unprotected sex
including anal, vaginal, and oral sex. This can happen when body
fluids such as semen (cum), vaginal fluids, or blood from an
infected person get into the body of someone who is not infected.
Everyone who has unprotected sex with an infected person is at
risk of contracting HIV, but people who already have another
sexually transmitted disease (STD) are even more at risk.
Children can be infected with HIV if an infected pregnant woman
passes the virus to her unborn child. Treating the mother and
child around the time the baby is delivered, delivering by cesarean
section, and avoiding breastfeeding can reduce the baby's risk
Reasons to Get Tested for HIV
If you have had unprotected sex (sex without a condom) or have
shared needles with someone else, you might want to consider
getting tested for HIV.
Early detection is key in fighting HIV and AIDS because:
- There is no cure for HIV, so early detection allows a person
to get medical treatment that can slow the advancement and
effects of the disease.
- Someone who learns he or she is infected can take the proper
steps and precautions to prevent spreading the disease.
- Couples who want to get pregnant can take action to try to
prevent their baby from being born with HIV.
Another reason to get tested is peace of mind: A negative test
result can be a big relief for someone who is worried that he or
she might be infected.
What the Tests Do
Most HIV tests don't actually look for the virus itself;
they look for the antibodies that indicate HIV is present in the
When someone has HIV, the body's immune system makes
antibodies to fight the virus. Unlike the antibodies our immune
systems make that successfully fight off other infections, the
antibodies to HIV cannot stop the virus. But their presence in
great numbers is what appears in test results. The antibodies can
take anywhere from 3 to 6 months to appear in detectable
quantities. So when someone has an HIV test, it may not
show an infection that could have occurred in the last 6
Types of HIV Tests
EIA or ELISA Tests.
These are the most common type of HIV test. Both tests have two
phases and it generally takes 1-2 weeks to get the results. The
first phase is the initial screening, which tests the blood
sample for HIV antibodies. If the screening results come back
positive, showing the presence of HIV antibodies, the screening
is repeated on the same sample.
If the EIA or ELISA test is positive for a second time, the
results are confirmed by another test called a Western blot. If
both of these tests are positive, the person is almost certainly
infected with the HIV virus. In rare cases, the EIA test can
produce false positives when antibodies other than the HIV
antibodies respond to the tests.
Rapid tests are the speedy alternative to the EIA and ELISA tests
- and they're just as accurate. While a standard blood test
takes between 1-2 weeks to return results, a rapid test is ready
in about 20 minutes. Rapid tests are not available in a lot of
places. Just like with the EIA and ELISA tests, the rapid tests
need to be confirmed with the Western blot test as well.
Many at-home testing kits are available over the counter or
online, but only one of them, the Home Access kit, is approved by
the U.S. Food and Drug Administration (FDA). The Home Access test
is available at most local drugstores and works in much the same
way a home diabetes test works. The user pricks his or her finger
and puts the blood on a specially prepared card. The card is then
sent into a laboratory, where it is analyzed and the results are
available (by phone with an anonymous identification number) in
about 7 days. There is also a Home Access Express kit, which can
provide anonymous results by the next business day. The Express
kit is slightly more expensive than the 7-day kit. The Home
Access test accurately identifies 99.5% of HIV negative blood
samples, and 100% of known positive blood samples.
Where to Get Tested
People can get tested for HIV at a variety of different places,
such as doctors' offices, health departments, hospitals, and
sites that specialize in HIV testing. Some places, like certain
clinics or hospitals, offer tests at little or no cost.
Anonymous Test Sites.
An anonymous test site will never ask for a person's name or
other identifying details. Instead, anyone being tested goes by a
number and he or she is the only one who knows the results of the
test. Although people go by numbers at anonymous sites, they
aren't treated like just another number. Many anonymous sites
have counselors available to talk with the person being tested,
both before and after testing. No written record of the test result
is kept at anonymous test sites.
Confidential Test Sites.
Confidential testing means that at a certain point in the process
the person being tested will need to identify themselves. The
results may appear as a written report in his or her medical
Every state has different laws pertaining to HIV testing, so
it's always a good idea to check to see what is available in a
If Test Results Are Positive
Someone who tests positive for HIV should:
- Contact a doctor immediately to discuss ways to slow the
progress of the infection. Often a doctor will do more tests to
evaluate the status of the virus. A person with a positive test
may want to talk to a doctor who is an HIV specialist.
- Stop any activity that has an adverse affect on the
body's immune system. These include excessive drinking, drug
use, unhealthy eating, and smoking.
- Have additional tests to look for the presence of other STDs
and diseases. When HIV was passed on, other STDs may have been
passed on as well. Because HIV weakens the immune system, an
HIV-positive person's body may need more help fighting off
People who discover they are HIV positive may feel frightened,
isolated, afraid to talk to friends and family, or worried that
they will be discriminated against or misunderstood. Talking to a
counselor or other mental health professional can help them deal
with these and other feelings.
Some health clinics that specialize in HIV and AIDS offer
counseling services or know of support groups for those living with
HIV. These safe environments offer a chance to discuss any fears
and get answers to questions from people who care and understand
what someone with HIV is going through.
There is no cure for HIV, but having the virus is not the death
sentence it once was. Governments and scientists are putting a lot
of money and research into treating - and, hopefully, eventually
curing or immunizing people against - HIV. With treatments
improving rapidly, people who find out they have the disease today
can look forward to living a normal life for many years to
Larissa Hirsch, MD
Date reviewed: November 2008
Note: All information is for educational purposes only. For specific medical advice,
diagnoses, and treatment, consult your doctor.
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