Am I Infected? <BR>(A Guide to Testing for HIV) : Printable Version

A Smart + Strong Site
Subscribe to:
E-newsletters
POZ magazine
JOIN AIDSMEDS YouTube
Am I Infected?
(A Guide to Testing for HIV)
en español

Printable Version


Introduction

Getting tested for HIV is a smart thing to do. Yet many people refuse to get tested. They find the idea of getting tested so frightening they just don't want to do it, even though they will often continue to be stressed and worried about whether they're infected. Others think of testing as unnecessary because they believe, or want to believe, that HIV is something that won't touch them.

Many times when someone gets tested, they happily find out their concern about being infected was unfounded. Getting the assurance of that negative test result can provide an enormous relief. It can also increase the motivation to take actions to stay negative. For others, getting tested and learning they are HIV positive is the first important step towards staying healthy.

The U.S. Centers for Disease Control (CDC) estimates there are about 1.1 million HIV-positive people in the United States. Of that number, the CDC estimates one in five (21 percent) are unaware of their HIV status. Often healthy in appearance and feeling well, they aren't receiving proper health care. Being unaware of their HIV status also makes it more likely they will unknowingly pass the HIV virus to others.

One of the most basic truths about HIV is that gender, age, race and economic status are irrelevant when it comes to vulnerability to HIV. Anyone can become infected. The HIV epidemic is going to be with us for a long time to come. At present there is no cure for HIV/AIDS, but there are medications that have proven to be very effective in keeping HIV-positive people alive longer and healthier.

Because knowing your accurate HIV status is essential to your good health, HIV testing is something everyone needs to know about.


What are the symptoms of HIV?

In the period immediately after infection has taken place there aren't any specific symptoms. Within two to four weeks after exposure to HIV, a person might have flu-like symptoms such as fever, swollen glands, muscle aches, diarrhea, fatigue or rash. In rare instances they may occur within a few days after the exposure has taken place.

These symptoms usually go away after a week or two. Often, if they occur at all, they're so mild they're hardly noticeable, although for some people they are severe enough to warrant calling a doctor.

It's important to keep in mind these symptoms are almost identical to those of many other illnesses. That's why testing is so important. Very often people who have the symptoms are worrying unnecessarily. Only by taking the HIV test can someone reliably know their HIV status. Everything else is just guessing and HIV is too important and issue to merely guess about.


What is an HIV test?

An HIV test shows if someone is infected with HIV, the virus that attacks the body's immune system and causes acquired immune deficiency syndrome, or what is more commonly known as AIDS. There are several different tests that can be used to determine if you are carrying the HIV virus. The first test developed is still the most frequently used for the initial detection of HIV infection: the enzyme-linked immunosorbent assay or as it's more commonly known, the ELISA or EIA.

There are a variety of ELISA/EIA tests available. Some involve drawing blood from a vain, with the sample sent to a laboratory for analysis, with results available within one or two weeks. Many testing sites are now using oral or finger prick rapid assays. The oral test, for example, involves swabbing the the upper and lower gums inside the mouth. The sample is then placed into a developer vial, with results available within 20 to 40 minutes. 

If the ELISA/EIA test is negative—meaning that antibodies are not found—the testing is complete. If the test is positive, additional testing is needed to make sure that it is not a "false positive" result (some molecules in the bloodstream can sometimes cause a false-positive result). First, you may need to repeat the ELISA or EIA test. If it's positive, a health care provider or testing site will draw blood for a test called a Western blot. If both the ELISA/EIA and the Western blot test yield a positive result, a diagnosis of HIV infection is confirmed.


When should you get tested and is the test result accurate?

There is a "window period" which is the time it takes the body to produce antibodies after HIV infection has begun. For the vast majority of those who will test positive, antibodies to HIV will develop within 4-6 weeks after exposure. Some will take a little longer to develop antibodies. To make certain that you receive a reliable test result, it's necessary to wait at least three months (13 weeks) after your last possible exposure to the virus before being tested.

Getting tested before three months may result in an unclear result or a false negative. Some testing centers may recommend testing again at six months. More than 99 percent of those who are going to seroconvert will do so within three months (seroconversion is the development of detectable antibodies to HIV in the blood as a result of infection.) It's extremely rare for seroconversion to take more than six months to develop detectable antibodies.

No diagnostic test will ever be 100 percent reliable, but if you test negative at the appropriate time (i.e., 13 weeks after possible exposure to the virus), you can consider that to be a dependable confirmation that you are HIV negative.


What are some of the other tests available?

These are other reliable, government-approved tests which are widely available:

Rapid Testing: Samples are obtained and analyzed using the ELISA test. The results are usually available within ten to sixty minutes. If the result is positive, a follow-up test is required, usually by drawing blood and sending the sample to a laboratory for Western blot testing. If the result is negative, there is no need for additional testing and the result can be considered conclusive.

Convenient and faster, this method is often used in healthcare settings, particularly where urgency is an issue such as with someone who is pregnant or about to give birth. Because it provides a result so quickly, this is an increasingly popular method for testing.

Several rapid HIV tests have been approved for the FDA, all of which can only be performed by healthcare providers (they cannot be purchased directly by consumers). The approved tests are the Oraquick Rapid HIV Antibody Test (using oral fluid or blood samples), the Oraquick Rapid HIV-1/2 Antibody Test (tests for both HIV-1 and HIV-2 using blood samples), the Clearview Complete HIV 1/2 and HIV 1/2 STAT-PAK (a blood sample is used to check for antibodies to HIV-1 and HIV-2), the Reveal Rapid HIV-1 Antibody Test (requires a blood sample), and the Uni-Gold Recombigen HIV Test (requires a blood sample). While the time to conduct each of these tests do vary, they all yield results in less than an hour. The FDA approved a rapid HIV test in November 2010, called the INSTI kit. It uses blood from a finger stick and provides results within 60 seconds. If you are interested in any of these tests, you should call your healthcare provider to see if he or she conducts these tests and, if not, where you may go to have one done.

The collection of oral fluids to look for HIV antibodies using the Oraquick Rapid HIV Antibody Test may not be as accurate as the other rapid assays that use blood samples. There were reports starting in 2005 that some testing sites in Los Angeles, San Francisco, and New York City had higher rates of false-positive test results than usual, meaning that the Oraquick Rapid HIV Antibody Test using oral fluids (but not blood samples) falsely detected antibodies in people who were not infected with HIV. Most—though not all—of these sites later found that there were problems with how the tests were being handled by providers. However, the test is still highly accurate in terms of detecting antibodies in people who are infected with HIV (it has an extremely low false-negative rate).

It's very important to understand these new tests do not change the length of time you have to wait after a possible exposure to HIV to get a reliable result. You still need to wait three months (13 weeks), to allow time for antibodies to become detectable in the blood for an accurate result.

The Oraquick, Clearview, Reveal Rapid, and Uni-Gold Recombigen tests are not the only rapid tests available. Some hospitals, clinics and a few private doctors' offices have their own in-house rapid tests, which are also completely reliable.
 

Home Sample Collection Tests: Using a provided safety lancet, you will need to prick your fingertip and place drops of blood on the blood specimen card included in the test kit. You only need enough blood to fill a circle the size of a dime. The kit will contain a unique identifying number that you'll need to have handy to learn the results. The blood specimen card is then sent to a designated laboratory where it is tested using the ELISA/Western blot tests. The results are usually available within three to seven days and are accessed by calling a telephone number provided by the laboratory. The results, along with counseling, are provided by trained counselors over the telephone.

The Home Access Kits are the only home-collection kits approved by the Food and Drug Administration (FDA) and is the only home sample collection test that should be used to check for HIV infection. The Home Access HIV-1 Test System provides results in seven business days (not including Sundays and Holidays) and The Home Access Express HIV-1 Test System provides results in three business days. These home-collection kits are available at most pharmacies or can be ordered from the manufacturer (Home Access Health Corporation): 1-800-448-8378, or www.homeaccess.com.
 

Oral Fluid Test: A device is used to collect oral (mouth) fluid (i.e. saliva). Oral fluids can contain antibodies to HIV, which can be detected using the ELISA and Western blot tests. The Oraquick Rapid HIV Antibody Test, which has a high degree of accuracy and produces results in less than an hour, can be conducted using oral specimens. Oral specimens are usually collected using the OraSure HIV-1 Oral Specimen Collection Device, which can then be tested using the rapid assay or traditional testing procedures. Because oral specimen collection is so easy and comfortable to accomplish, this test is often used in clinics, doctors' offices, hospitals, and school-based and university health centers.
 
Urine-Based Test: A urine sample, collected in a cup, is used for the ELISA/Western blot tests. The results of this noninvasive and non-technical method can be obtained at a return visit, typically in one to two weeks. It's commonly used in community-based and outreach settings, adolescent, school and university-based settings. Anyone with a positive urine result must have a confirmatory blood test.


I can't wait 13 weeks to find out! Are there other options?

There are tests that can look for the virus—not antibodies—in the blood. Because the virus becomes detectable in the blood much sooner after infection than antibodies, these tests are an option for people who simply can't wait 13 weeks to find out the results of standard ELISA/EIA and Western blot testing.

These tests look for HIV, either floating around freely in the bloodstream or inside cells in the bloodstream. Some tests—known as qualitative tests—yield a "positive" or "negative" result, meaning that the virus was or wasn't found (GenProbe's Aptima HIV-1 RNA Qualitative Assay is the only test approved for this purpose). Other tests—known as quantitative tests—yield a "viral load" result, meaning the amount of virus in a sample of blood. Roche's quantitative Amplicor HIV Monitor Test is frequently used by doctors and research centers but is not specifically approved for this purpose. It is only approved to monitor to people who are known to be infected with HIV, particularly to find out if their treatment is working properly.

These tests are highly sensitive, meaning that they can detect even the tiniest amounts of HIV in a blood sample. However, they are not always specific, meaning that they can sometimes yield a false-positive result. In turn, follow-up testing using standard ELISAEIA and /Western blot assays, is typically recommended.

Also available are tests that look for both HIV proteins (antigens) and antibodies in a blood sample. One example is Abbott's Architect HIV Ag/AB Combo assay.  This particular test can detect HIV up to 20 days earlier than antibody-only tests.

These tests must be ordered by a health care provider, meaning that you should call your doctor if you think you may have recently been exposed to the virus and would like one of these tests. It's also important to keep in mind that some of these tests, notably the qualitative and quantitative assays, can be expensive and are not usually covered by insurance for diagnostic purposes.


What viral tests are available?

There are a number of tests that look specifically for the virus. Generally speaking, these tests yield conclusive results within 48 to 72 hours after infection has occurred. However, in some case, it can take as long as 28 days for results to be considered accurate.

P24 Antigen Test: This test uses ELISA technology to look directly for key pieces of the HIV virus – the p24 protein found on HIV's outer coat. This test can reduce the chance of a false-negative in standard (antibody) ELISA testing is done too early (i.e., less than 13 weeks after exposure). The p24 antigen test may be ordered if there's been a very recent risky exposure to HIV, such as a healthcare work-related incident. Blood banks also use it for screening donations.

Valuable in detecting HIV infection early in the window period after exposure, this test is only useful for a period of approximately three weeks after exposure, before the production of antibodies begins. A p24 test result should be confirmed by antibody testing once the window period has passed.
 

Quantitative Polymerase Chain Reaction (PCR): The quantitative PCR, also known as the viral load test, is considered to be highly reliable for someone who may have recently been exposed to the virus, particularly in a high-risk situation. If the virus is present, the quantitative PCR will reveal how much virus is in a person's bloodstream (the viral load). In most cases, a quantitative PCR is highly accurate within 48 to 72 hours. However, a small number of people don't have viral loads that are high enough to confirm a diagnosis until 28 days after exposure. The most widely available quantitative PCR test, Amplicor® version 1.5, can detect subtypes A through G, which account for 99.96% of HIV infections in the U.S.

The standard recommendation is that a negative PCR result be confirmed with an ELISA test at 13 weeks.
 

Qualitative PCR: The qualitative PCR, also known as the PCR-DNA test, looks for DNA in cells that suggest that HIV infection has taken place. It is not a viral load test, meaning that it will only determine if the virus is present, not how much virus is present. This test is frequently used to determine if an infant born to an HIV-positive is infected with the virus, given that it can detect virus before viral load becomes detectable. However, it's not at all clear if the qualitative PCR test has any advantages over the quantitative PCR test, which appears to be just as reliable, more widely available, and cheaper to perform.
 
Branched DNA Assay: Like the quantitative PCR test, the branched DNA (bDNA) assay can determine how much virus is present in someone who has been infected with the virus. The results of bDNA testing are comparable to those of quantitative PCR testing and there are no known advantages of using bDNA testing over quantitative PCR testing for diagnostic purposes. This test is known as the Quantiplex® HIV-RNA Assay and is available through most commercial laboratories.


Aren't there two different kinds of HIV? How do I know what I should be tested for?

The two known types of HIV are HIV-1 and HIV-2. In the United States and Europe, the overwhelming majority of HIV cases involve HIV-1. HIV-2 infections are predominantly found in West African nations. The first case of HIV-2 was discovered in the United States in 1987. Since then only 79 people with HIV-2 infections have been identified in the United States. While the CDC does not recommend routine screening for HIV-2, when someone tests for HIV-1 using ELISA/Western blot tests, there is a 60 to 90 percent chance that HIV-2 will be detected if it is present.

Not every test will automatically include testing for HIV-2. Anyone who thinks there's a possibility they have been exposed to HIV-2 and/or any of HIV's more rare subtypes should mention this when being tested. Among those for whom HIV-2 testing is indicated are those with sex partners from a country where HIV-2 is prevalent or people with an illness that indicate underlying HIV infection, such as an opportunistic infection, but whose HIV-1 test result was negative.


What about subtypes of HIV?

Thus far, 11 distinct subtypes, also known as "clades" or "genotypes," have been recognized of HIV-1. More than 96% of the HIV-1 infections in the United States and Europe are caused by subtype B. Subtypes B and F predominate in South America and Asia. Subtypes A through H of HIV-1 are found in Africa, along with HIV-2 in sub-Saharan Africa.

The ELISA/Western blot tests can detect antibodies to all HIV-1 subtypes. Viral load tests can also detect and quantify subtypes of HIV-1. The viral load tests can also detect and quantify HIV-2.


Should I get tested for HIV?

Getting tested is recommended if any of the following apply to you:

You should be tested at least once a year if you are sexually active, particularly with three or more sexual partners in the last 12 months.
You had a possible exposure to HIV either through vaginal or anal intercourse without the use of a condom or have been involved in any other risky sexual behavior.
You have shared/reused needles or syringes to inject drugs (including steroids), or for body piercing, tattooing, or any other reason.
You are a health care worker who's had a work-related accident such as direct exposure to blood or have been stuck with a needle or other object.
You are uncertain about your sexual partner's risk behaviors or your sexual partner has tested positive for HIV.
You are pregnant or are considering becoming pregnant.
You have had certain illnesses including TB (tuberculosis), or an STI (sexually transmitted infection), such as syphilis or herpes.
You have any reason to be uncertain about your HIV status. 

If you have engaged in behaviors that have put you at risk of becoming infected with HIV, you may also have been exposed to other STIs. Some of these can be quite serious and require immediate treatment, such as syphilis or hepatitis C virus (HCV). If you are being tested for HIV you should also discuss with your provider whether you are at risk and should be tested for these STIs.


Common myths about how HIV is spread

These are some of the circumstances you don't have to worry about because they will not put you at risk for becoming infected with HIV:

Being bitten by a mosquito or other bugs, being bitten by an animal.
Eating food handled, prepared or served by somebody who is HIV positive.
Sharing toilets, telephones or clothing.
Sharing forks, spoons, knives, or drinking glasses.
Touching, hugging or kissing a person who is HIV positive.
Attending school, church, restaurants, shopping malls or other public places where there are HIV-positive people.
HIV cannot be transmitted though urine, feces, vomit, or sweat. It is present, but only in negligible quantities, in tears and blister fluid. It is present in minute amounts in saliva in a very small number of people.


Why do I need to know my status?

With regard to HIV, IGNORANCE IS DEFINITELY NOT BLISS.

Not knowing your HIV status can be very dangerous. If you test positive, knowing your status as early as possible after seroconversion has taken place puts you in the best position to preserve your health, as well as that of your partner(s), and your children, if you have or are planning to have a family.

Effective medications and good health care are enabling many thousands who are HIV-positive to live successful and fulfilling lives. Not knowing if you are HIV positive means you are not getting the health care you need to stay well. You may also be putting others in your life at risk.

If you test negative, that knowledge can be a powerful incentive to consistently follow the guidelines that will help you to remain HIV negative. It can also spare you a lot of unnecessary worrying and stress that often occurs when someone's uncertain about their status.


What's the difference between anonymous & confidential testing?

With anonymous testing, you don't have to give your name to anyone. With confidential testing, you supply your name during the testing process, but the healthcare system and government health agencies are required by law to keep your testing information confidential – they can't let it become public information.

In the United States, your medical records are confidential. They're protected by the Privacy Act, which was passed into law in 1974. Generally speaking, only your doctor or the facility where you have your test done have access to your medical records. However, laws vary from state to state with regard to their being required to report when someone tests positive. For instance, if you live in a state where reporting of communicable diseases is required, your doctor must report your positive test result – which will likely include your name – to the state and federal governments.

Anyone who is concerned about anonymity or disclosure should contact their local health department or any AIDS service organization hotline to find out what the law is in their area and where anonymous testing is available.

A home test, or going to an anonymous testing site – which are available through departments of health in all the states – are good ways of getting tested anonymously, which means that your name does not need to be used in order to have the test. You will have a conversation with a counselor, but your identity will still be protected.


Where can I get tested?

Since 2006, the U.S. Centers for Disease Control and Prevention (CDC) has recommended regular HIV testing for all adolescents and adults residing in the United States. In turn, HIV testing is widely available at a number of health facilities -- in private medical practices, public health clinics, hospital emergency rooms, pharmacies and  mobil testing vans run by clinics and health organizations. 

The CDC has instructed health care providers to test all their patients for the virus, regardless of whether or not they have reported sexual or drug-using behavior known to transmit the virus. Unfortunately, however, many health care providers still aren't following this advice, which means that many people who are unknowingly living with HIV continue to go undiagnosed.

Home HIV testing is also a possibility. U.S. residents can purchase home collection kits that involve sending a blood sample to a laboratory for analysis and results. And beginning in October 2012, U.S. residents will be able to purchase a complete do-it-yourself kit that can provide results within 20 to 40 minutes.

It's important for you to be aware that counseling is an important part of HIV testing. It may be done face-to-face with a doctor, at a testing site with a counselor, or over the phone with a counselor working for a home testing kit company. These conversations play a valuable role in informing anyone who's tested negative about maintaining their negative status and advising those who test positive about their health care.

When it comes to HIV testing, the old cliché, "knowledge is power," still holds true. Knowing your accurate HIV status, whether negative or positive, puts you in the best position to protect your health.

Every state has its own HIV Hotline where information can be obtained about where to get tested, including anonymously, in those states in which anonymous testing is available.

Some useful phone numbers:

CDC National STD and AIDS Hotlines for testing referral information:

  • 1-800-342-2437 (English)
  • 1-800-344-7432 (Spanish)

Last Revised: June 04, 2013

This content is written by the POZ and AIDSmeds editorial team. For more information, please visit our "About Us" page.

TREATMENT NEWS
Research updates

> More Treatment News

Search for news stories about this topic

Lesson Index
Collapse All | Up One Level

TALK TO US
Tell us what you think
Poll
Have you visited your health care provider within the last 4 months?
Yes
No


Survey
AIDSmeds Reader Survey

more surveys

[ about AIDSmeds | AIDSmeds advisory board | our staff | advertising policy | advertise/contact us]
© 2014 Smart + Strong. All Rights Reserved. Terms of use and Your privacy.
Smart + Strong® is a registered trademark of CDM Publishing, LLC.