January 2011    View PDF    Email a question    En español
If you believe you’ve been exposed to HIV, it will take about 4–6 weeks for your body to make enough antibodies for an HIV test to find. Antibodies are proteins that your immune system makes in reaction to an infection. Therefore, getting an antibody test soon after the exposure won’t give you an accurate result from that exposure.
Although it may be difficult to wait, you will need to wait about 4–6 weeks before you take the test. If the test shows you have these antibodies, then it means you have HIV. Antibody tests are more than 99.9% accurate.
Sometimes people take a second test to confirm the result and ease their doubts about the first result. However, labs normally test blood two different ways to confirm a positive result. So, if your test result comes back positive, your blood or saliva was already tested twice. If you don’t have these antibodies, you’re considered HIV-negative.
If you tested negative, then you should test again a few months later to confirm you’re HIV-negative. Some people will test again at 6 months to further ease their minds. However, it’s rare that it takes more than 6 months before the test gives a definitive answer.
In some cases, the test result may be indeterminate. This usually occurs when the test is taken too early after the exposure. If this happens, you should repeat the test awhile later.
The standard antibody test is not reliable to test newborns of HIV-positive women. Since babies are born with their mother’s antibodies, special tests must be used to tell if a baby is infected.
In the case of PEP, or post-exposure prevention, an HIV test will be part of your first PEP visit. Your doctor may have a rapid test available that gives you an immediate result. This only tells you if you have HIV from an earlier exposure, not from the recent exposure to HIV that has led to an established infection.
Sometimes, individuals find themselves worrying about an exposure although several test results show they’re negative. In this case, it can be helpful to seek a counselor or social worker who can help sort through the feelings of being worried well.
Why not use other types of HIV tests?
Viral load tests are used to find the amount of virus in the blood of HIV-positive people and to check their disease progression. These tests are not reliable to test for initial HIV infection. They cost a lot more than antibody tests and they have a significant false positive rate. That means the test sometimes suggests that someone is infected when in fact s/he is not.
Another test, called a nucleic acid test or NAT, can find genetic pieces of HIV within about 2 weeks of infection. These are used by blood banks to screen donated blood for various infections. NATs are not routinely used to screen people, but are sometimes used if a person feels compelled enough to have one done. An NAT may not be available to all people or covered by insurance.
Going to your doctor’s
If you have a doctor that you usually see, you might choose to call for an appointment. S/he can order an HIV test for you. Your doctor will either sample your blood or saliva, or send you to a lab to get it done.
The benefit of going to your doctor is that you may already have a good relationship and feel at ease talking to her or him about HIV. The drawback is that s/he may not be well trained in providing counseling before and after testing. A trained counselor can often provide you with referrals to local resources.
Going to a local testing site or community event
You may not want to see your regular doctor. In this case, you can find an anonymous and confidential testing site near you by going online to www.hivtest.org, or call Project Inform’s HIV Health Infoline at 1-800-822-7422.
These sites usually provide counseling free of charge along with the screening. They usually can refer you to resources in your area and provide you emotional support. And, if you do test positive, they can help you cope with the news. Some sites use standard tests that give results in a week or so. Many sites have saliva-based rapid tests with results in about 20 minutes.
You can also get tested for HIV in many other places, such as an emergency room, health fair, health department, public health clinic or AIDS organization. These vary in the types of tests they use and whether or not you have to pay for them. Investigate which place is best suited to your needs.
Using an in-home kit
Perhaps you feel uneasy talking to someone face-to-face or fear going to an HIV testing site. In this case, you can test by using an in-home collection kit. Two slightly different Home Access kits can be bought at many drug stores or online (www.homeaccess.com), but they’re not available in every state.
The kit includes a booklet about HIV testing as well as instructions, needle, small blotter pad and postage-paid envelope. You will also find a unique ID code that you must use to get your results.
After you’ve mailed your blood sample in, you will call and talk to a counselor who will ask for your ID code, explain your test results and answer your questions. The counselor can give you referrals for HIV prevention or other services in your area.
The kit costs $45–$60; but before you choose to test this way, consider how you feel about being counseled and knowing your HIV status over the phone. The only FDA-approved test kits are the two test systems from Home Access. Other tests are not proven reliable.