How Is It Used
HIV antibody and HIV antigen testing is used to screen for and diagnose HIV infections. Early detection and treatment of HIV infection and immune system monitoring can greatly improve long-term health and survival. Also, if a person knows his or her HIV status, it may help change behaviors that can put him or her and others at risk.
Screening
Different types of tests may be used for HIV screening:
There are a few different ways a person can get access to HIV screening:
Diagnosis
What Happens During An Hiv Test
You will either get a blood test in a lab, or do your own test at home.
For a blood test in a lab:
- A health care professional will take a blood sample from a vein in your arm, using a small needle. After the needle is inserted, a small amount of blood will be collected into a test tube or vial. You may feel a little sting when the needle goes in or out. This usually takes less than five minutes.
For at home test, you will need to get a sample of saliva from your mouth or a drop of blood from your fingertip.
- The test kit will provide instructions on how to get your sample, package it, and send it to a lab.
- For a saliva test, you will use special spatula-like tool to take a swab from your mouth.
- For a fingertip antibody blood test, you will use a special tool to prick your finger and collect a sample of blood.
For more information on at-home testing, talk to your health care provider.
Infections With Multiple Strains
When the virus multiplies, the copies sometimes change and develop into another HIV strain in your body. You can end up with a strain your HIV drugs won’t work against. This makes your viral load — the amount of HIV in your body — go up. In that case, you’d need another type of treatment.
You also can have two or more strains if you were infected by more than one person. This is called superinfection. Superinfection is rare — it happens in less than 4% of people. You’re at the highest risk of superinfection in the first 3 years after you get HIV.
Everyone reacts differently to infection. You might not notice any change in your symptoms or viral load with a new infection. But it can make your HIV worse, especially if you have a strain drugs won’t work well against. If that happens, the drugs you take for your original HIV strain won’t necessarily treat the new strain.
AIDSinfo: “HIV-1.”
AVERT: “HIV Strains and Types.”
CDC: “Morbidity and Mortality Report: HIV-2 Infection Surveillance — United States, 1987–2009,” “Infection with more than one HIV type .”
HIV Sequence Database: “HIV and SIV Nomenclature.”
Minnesota Department of Health: “HIV Drug Resistance and Subtype Testing: Information for Clients.”
Motomura, K. Journal of Virology, 2008.
Nyamweya, S. Reviews in Medical Virology, 2013.
Plantier, J. Nature Medicine, 2009.
Public Library of Science: “The Two-Phase Emergence of Non-Pandemic HIV-1 Group O in Cameroon.”
Recommended Reading: Where Can You Test For Hiv
Can I Take The Test At Home
At-home HIV tests are a convenient way to take an HIV test in a private location. Testing for HIV at home is a form of HIV screening that requires additional follow-up if preliminary results are positive. At-home HIV tests can be obtained online, at a pharmacy, or at health departments and community-based organizations.
What Does A Positive Hiv Test Result Mean

If you have a positive HIV test result, a follow-up test will be conducted. If the follow-up test is also positive, it means you are HIV-positive.
If you had a rapid screening test, the testing site will arrange a follow-up test to make sure the screening test result was correct. If you used a self-testing kit at home, a positive HIV test result must always be confirmed by additional HIV testing performed in a health care setting. If your blood was tested in a lab, the lab will conduct a follow-up test on the same sample.
If your follow-up test result confirms you are infected with HIV, the next thing is to take steps to protect your health and prevent transmission to others. Begin by talking to your health care provider about antiretroviral therapy . ART is the use of HIV medicines to treat HIV infection. People on ART take a combination of HIV medicines every day. ART can keep you healthy for many years and greatly reduces your chance of transmitting HIV to your sex partner if taken the right way, every day. Your health care provider will help you decide what HIV medicines to take.
If you have health insurance, your insurer is required to cover some medicines used to treat HIV. If you dont have health insurance, or you need help because your insurance doesnt pay for the treatment you need, there are Federal resources that may help you.
To lower your risk of transmitting HIV,
Also Check: What Is Hiv 2 Antibody
How Does Hiv Testing Work
In the early stages of HIV infection, the virus itself is difficult to detect. Rather than looking for the virus, HIV testing usually involves looking at the body’s reaction to the presence of the virus. The measure of the amount of virus in an individual’s blood stream is called the viral load.
Antibodies are produced by the body in reaction to the presence of a virus. An HIV antibody test measures the presence of antibodies in response to the presence of HIV. The most common HIV antibody tests are ELISA and Western Blot. These tests can now be performed on samples of oral fluid.
What Is Rapid Hiv Testing
There are now many tests available which can detect HIV antibodies within a few minutes. Examples of rapid tests include OraQuick, which can detect antibodies in 20 minutes and is the only rapid test that can use oral fluid, and INSTI, which can detect antibodies in under a minute. Other rapid tests are available as well. The technology involved in rapid testing is quite advanced and for any of the various tests, the results are over 99% accurate.
Most community-based organizations who conduct HIV testing in Louisiana follow a rapid-rapid testing model. This means that you will have a rapid test done during your visit and then, if that test is positive, you will have a second test done to verify your result. If both results are positive, you will be offered a referral to medical care. In the very rare event that the second test is negative, your counselor will advise you about next steps.
Don’t Miss: How To Take Hiv Test At Home
What Is It Used For
An HIV test is used to find out if you have been infected with HIV. HIV is the virus that causes AIDS . Most people with HIV don’t have AIDS. People with AIDS have an extremely low number of immune cells and are at risk for life-threatening illnesses, including dangerous infections, a severe type of pneumonia, and certain cancers, including Kaposi sarcoma.
If HIV is found early, you can get medicines to protect your immune system. HIV medicines may prevent you from getting AIDS.
What Do The Results Mean
If your result is negative, it can mean you don’t have HIV. A negative result may also mean you have HIV but it’s too soon to tell. It can take a few weeks for HIV antibodies and antigens to show up in your body. If your result is negative, your health care provider may order additional HIV tests at a later date.
If your result is positive, you will get a follow-up test to confirm the diagnosis. If both tests are positive, it means you have HIV. It does not mean you have AIDS. While there is no cure for HIV, the disease can be effectively controlled with medicine. The medicine used to treat HIV is called antiretroviral therapy . ART can significantly reduce the amount of HIV in the blood. People with HIV who take ART before the disease gets too advanced can live long, healthy lives. If you are living with HIV, it’s important to see your health care provider regularly.
Also Check: How Can One Contract Hiv
Why Do I Need An Hiv Test
The Centers for Disease Control and Prevention recommends that everyone between the ages of 13 and 64 get tested for HIV at least once as part of routine health care. You may also need an HIV test if you are at higher risk for infection. HIV is mainly spread through sexual contact and blood, so you may be at a higher risk for HIV if you:
- Are a man that has had sex with another man
- Have had sex with an HIV-infected partner
- Have had multiple sex partners
- Have injected drugs, such as heroin, or shared drug needles with someone else
HIV can spread from mother to child during birth and through breast milk, so if you are pregnant your doctor may order an HIV test. There are medicines you can take during pregnancy and delivery to greatly reduce your risk of spreading the disease to your baby.
Can You Use The Hiv Antibody Test To Detect Hiv In Newborns
No. Because maternal antibodies are transferred from mother to baby and stay in the newborn’s system for 6-12 months, a different test must be used. A test that detects the genetic material, either an HIV RNA or HIV DNA test, is required.
Conditions: HIV Infection and AIDS
Screening: Pregnancy, Newborns, Teens, Young Adults, Adults, Adults 50 and Up
In the News: HIV Testing Remains Vital Despite Second “Cured” HIV Patient , On the Horizon: A Better HIV Saliva Test
Elsewhere On The Site
Read Also: What Are The Side Effects Of Hiv Aids
Understanding A Positive Result
What does a positive result mean?
If you use any type of antibody test and have a positive result, you will need another test to confirm your results.
- If you test in a community testing program or take a self-test and its positive, you should go to a health care provider to get follow-up testing.
- If your test is done in a health care setting or a lab and its positive, the lab will conduct the follow-up testing, usually on the same blood sample as the first test.
If the follow-up test is also positive, it means you have HIV .
It is important that you start medical care and begin HIV treatment as soon as you are diagnosed with HIV. Antiretroviral therapy or ART is recommended for all people with HIV, regardless of how long theyve had the virus or how healthy they are. HIV medicine works by lowering the amount of virus in your body to very low levels. HIV medicine can make the viral load so low that a test cant detect it . HIV medicine slows the progression of HIV and helps protect your immune system. If you take HIV medicine as prescribed and get and keep an undetectable viral load, you can stay healthy for many years. Having an undetectable viral load also helps prevent transmitting the virus to others. For example, if you have an undetectable viral load, you have effectively no risk of transmitting HIV to an HIV-negative partner through sex.
When To Get A Test

Right after you’re diagnosed, you should get a viral load test for a “baseline measurement.” That gives your doctor something to compare future test results to.
When you start or change medicine, a test about 4 weeks afterwards helps your doctor decide how well it’s working. An effective drug combination, taken as prescribed, can often drop the HIV viral load to one-tenth of what it was within a month. The viral load is generally undetectable by 3 months, nearly always by 6 months.
After that, you should get a test as often as your doctor recommends to see how your medications are controlling the virus. If your HIV seems to be under control, you can probably be tested less frequently.
Read Also: Can You Detect Hiv In Urine
If You Have A Negative Test Result Does That Mean That Your Partner Is Hiv
No. Your HIV test result reveals only your HIV status.
HIV is not necessarily transmitted every time you have sex. Therefore, taking an HIV test is not a way to find out if your partner is infected.
It’s important to be open with your partner and ask them to tell you their HIV status. But keep in mind that your partner may not know or may be wrong about their status, and some may not tell you if they have HIV even if they know they’re infected. Consider getting tested together so you can both know your HIV status and take steps to keep yourselves healthy.
What Does The Test Measure
HIV tests detect the presence of the HIV virus, HIV antigens, and/or HIV antibodies. If these substances are detected, the test returns a positive result for HIV.
There are three types of HIV tests available:
- Antibody test: Antibodies are produced by the body after an HIV infection. It can take weeks for the body to produce antibodies, so HIV antibody tests can only detect HIV from 3 to 12 weeks after infection.
- Antigen/antibody test: Antigens are foreign substances that activate an immune response. Antigens appear before the body produces antibodies, so HIV antigen/antibody tests can detect an HIV infection earlier than antibody tests, within 2 to 4 weeks of becoming infected.
- HIV viral load test: An HIV viral load test looks for the quantity of HIV virus in the blood. In addition to detecting an HIV infection, viral load testing can also detect how much of the virus is in the blood. Although this type of testing can detect an HIV infection earlier than other HIV tests, its very expensive and is typically only used when someone has symptoms or a possible exposure to HIV.
Read Also: Is It Hard To Get Hiv
Is There Anything Else I Should Know
HIV infection cannot be cured, but early diagnosis allows for treatment with antiretroviral therapy that can help to suppress levels of virus in the body and greatly improve long-term health. People typically take at least three drugs from two different classes in order to prevent or minimize virus replication and the emergence of drug-resistant strains. Combinations of three or more antiretroviral drugs are referred to as highly active antiretroviral therapy or HAART.
There is currently no vaccine to protect against HIV, but avoiding high-risk activities such as having unprotected sex and sharing needles for injecting drugs can help to prevent its spread. Early diagnosis of HIV infection is important to prevent its transmission to others and to allow evaluation, monitoring, and early treatment of the affected person.
While there is no vaccine, the U.S. Centers for Disease Control and Prevention and the World Health Organization recommend that individuals without HIV infection but at high risk for it consider taking pre-exposure prophylaxis , a daily pill to help prevent infection. For people taking PrEP consistently, the risk of HIV infection was up to 92% lower compared to those who didn’t take it.
Healthcare workers can protect themselves from HIV infection by following universal precautions, such as wearing gloves and avoiding needle sticks.
Stage : Acute Hiv Infection
Stage 1 of the HIV infection is known as acute HIV infection. At this stage, the immune system attempts to attack the virus by producing HIV antibodies. This process is called seroconversion.
Seroconversion usually takes place within a few weeks of infection. These antibodies will stick around and remain detectable for many years.
As a result, someone who is living with HIV will continue to test positive on HIV tests. That is true even if their viral load is undetectable.
Within two to four weeks of being infected, those with HIV may experience:
- Fever
Symptoms may be absent in some people, however.
You May Like: What Is Hiv Positive But Undetectable
What The Results Mean
A high viral load is generally considered about 100,000 copies, but you could have 1 million or more. The virus is at work making copies of itself, and the disease may progress quickly.
A lower HIV viral load is below 10,000 copies. The virus probably isn’t actively reproducing as fast, and damage to your immune system may be slowed, but this is not optimal.
A viral load that can’t be detected — less than 20 copies — is always the goal of HIV treatment. This doesn’t mean you’re cured. Unfortunately, the virus is still able to survive in various cells in the body. But maintaining an undetectable viral load is compatible with a normal, or near-normal life span. Continuing to take your medicine as prescribed to keep the virus undetectable is very important.
When your HIV viral load is undetectable, there is little to no risk of infecting others, but most doctors still advise using condoms to prevent acquiring other strains of HIV and other sexually transmitted infections.
Hiv Testing After Diagnosis
Additional tests are performed both after a person receives an HIV-1 diagnosis and throughout their treatment. These include:
- Viral load. The amount of virus in a persons blood is called viral load. When HIV-1 isnt treated, viral load will increase. In contrast, treatment with antiretroviral drugs can reduce viral load to undetectable levels.
- CD4 count. A CD4 count looks at the number of CD4 cells in a blood sample. Decreasing levels of CD4 cells signal damage to the immune system.
- Drug resistance testing. HIV-1 can become resistant to certain types of antiretroviral drugs. Because of this, drug resistance testing is performed to help inform which antiretroviral drugs can be used for treatment.
HIV is a viral infection. A person can contract HIV-1 when bodily fluids that contain the virus come into contact with their blood or with mucous membranes like those found in the genitals, anus, or mouth.
There are several bodily fluids that can transmit HIV-1. These include:
- blood
- workplace exposures, such as accidental needlesticks or sharps injuries
- receiving a blood transfusion or organ transplant
- getting a tattoo or piercing with equipment that hasnt been properly sterilized
- human bites that break the skin
Don’t Miss: What Happens If Your Hiv Positive And Pregnant