If I had unprotected sex, on a one night stand, and am going for an HIV and STD test; how quickly will the tests reveal an infection? Is there a window period, or will infection be evident immediately?
An HIV infection will generally not be evident immediately as it can take some time for the immune system to produce enough antibodies for the antibody test to detect. The CDC (Centers for Disease Control and Prevention) provides the following information on the “window period” you referred to in your question:
How long after a possible exposure should I wait to get tested for HIV?
Most HIV tests are antibody tests that measure the antibodies your body makes against HIV. It can take some time for the immune system to produce enough antibodies for the antibody test to detect and this time period can vary from person to person. This time period is commonly referred to as the “window period”. Most people will develop detectable antibodies within 2 to 8 weeks (the average is 25 days). Even so, there is a chance that some individuals will take longer to develop detectable antibodies. Therefore, if the initial negative HIV test was conducted within the first 3 months after possible exposure, repeat testing should be considered >3 months after the exposure occurred to account for the possibility of a false-negative result. Ninety seven percent will develop antibodies in the first 3 months following the time of their infection. In very rare cases, it can take up to 6 months to develop antibodies to HIV.
Another type of test is an RNA test, which detects the HIV virus directly. The time between HIV infection and RNA detection is 9-11 days. These tests, which are more costly and used less often than antibody tests, are used in some parts of the United States.
The CDC also provides information on the types of HIV tests and how long you need to wait on results:
The most common HIV tests use blood to detect HIV infection. Tests using saliva or urine are also available. Some tests take a few days for results, but rapid HIV tests can give results in about 20 minutes. All positive HIV tests must be followed up by another test to confirm the positive result. Results of this confirmatory test can take a few days to a few weeks.
For information on HIV testing, you can talk to your health care provider or you can find the location of the HIV testing site nearest to you by calling CDC-INFO 24 Hours/Day at1-800-CDC-INFO (232-4636), 1-888-232-6348 (TTY), in English, en Español. Both of these resources are confidential. You can also get an HIV test at a Planned Parenthood health center.
As for STD testing, the type of test used and the wait time for results depends on the STD being tested for. Physical exams that reveal a rash, discharge, sores, or warts associated with an STD will give you immediate results. STDs that require blood, urine, discharge, tissue, cell or saliva samples will require lab testing – results for these types of tests might not be available for several days or weeks.
You can get tested for STDs through your primary care physician or gynecologist. If you don't have a doctor and live in northern New Jersey, you can call the Adolescent/Young Adult Center for Health at 973-971-5199 for an appointment with an adolescent medicine specialist or contact your local teen health center or Planned Parenthood. You can also search the CDC National HIV and STD Testing Resources webpage for STD testing locations near you.
If you have had unprotected sex, FX can imagine there will be a lot of anxieties about things like unwanted pregnancies and/or the transmission of STDs, including HIV. FX recommends that if you have had unprotected sex you contact your doctor as soon as possible so you can have the guidance and support you need as you move forward. It can take up to three months for HIV to show up on a test, but it only takes days for STDs such as gonorrhea, Chlamydia and syphilis to show up. So you don’t want to wait too long before speaking with someone about it. It would also be advised to avoid sexual contact until you have been tested and know that you are in the clear. If you do have sex before testing, or before getting the results of your tests, be sure to inform your partner that it is possible you have an STD that hasn’t been diagnosed yet (which means you could still pass it on) and be sure to use a condom if your partner agrees to have sex with you knowing this information.
FX also recommends that you speak to your doctor about safer sex practices. IF you have an STD it is important to know how to prevent from passing it onto others. If it turns out you do not have an STD than make sure you practice safer sex by using a condom each and every time you have sex to help prevent any future transmissions.
Again, if you don't have a doctor and live in northern New Jersey, you can call the Adolescent/Young Adult Center for Health at 973-971-5199 for an appointment with an adolescent medicine specialist or contact your local teen health center or Planned Parenthood.