How Are Testing Technologies Used To Diagnose Hiv Infection
To test for HIV, a sample of a persons blood is taken. With the most common test, a vial of blood taken from a vein is sent to a laboratory to be tested for HIV . There are also rapid tests available, which use a drop of blood from a finger prick to test for HIV immediately after the sample is taken.
What Does A Negative Hiv Test Result Mean
A negative result doesn’t necessarily mean that you don’t have HIV. That’s because of the window periodthe time between when a person gets HIV and when a test can accurately detect it. The window period varies from person to person and is also different depending upon the type of HIV test.
Ask your health care provider about the window period for the kind of test youre taking. If youre using a home test, you can get that information from the materials included in the tests package. If you get an HIV test after a potential HIV exposure and the result is negative, get tested again after the window period for the test youre using to be sure. To learn more about the window period and when a person should get retested, see CDCs How soon after an exposure to HIV can an HIV test if I am infected?. If you get an HIV test within 3 months after a potential HIV exposure and the result is negative, get tested again in 3 more months to be sure.
If you learned you were HIV-negative the last time you were tested, you can only be sure youre still negative if you havent had a potential HIV exposure since your last test. If youre sexually active, continue to take actions to prevent HIV, like using condoms the right way every time you have sex and taking medicines to prevent HIV if youre at high risk.
Why Should You Have An Hiv Test
- Federal guidelines recommend that everyone ages 13-64 get tested for HIV at least once in their lifetime. People at higher risk, such as people with more than one sex partner in the year, people diagnosed with sexually transmitted infections, sexually active men who have sex with men, and people who inject drugs should get tested at least 1-3 times per year.
- Getting tested for HIV can give you important information and help keep you and others safe. Knowing your HIV status is vital to your health. If you find out you are HIV-positive, you will be linked to medical care immediately that improves your health, prolongs your life, and greatly lowers your chance of spreading HIV to others.
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What Does Non Reactive Hiv 1/2 Eia Screen Mean
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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.
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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.
What Does A Reactive Test Result Mean
A reactive test result is a possible positive result, but means that you will need to go back to test again to confirm this. The healthcare worker will talk you through everything you need to know and help you with;any worries that you may have.
You will need to give blood sample, which will then be sent to the lab for testing. At this stage, it’s very important to follow the advice of the healthcare professional.
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Will My Partner Have The Same Results As Me
Dont assume that if you are positive, or negative, your partner will have the same result. It may be that your partner has a different test result to you. This is why its a good idea to encourage your partner to get tested too, whether your results are positive or negative. If youre worried about telling your partner that you are positive or asking them to take a test, speak to your healthcare advisor. They can often help you with ways to do this.
Discusses Physiology Pathophysiology And General Clinical Aspects As They Relate To A Laboratory Test
AIDS is caused by 2 known types of HIV. HIV type 1 is found in patients with AIDS, AIDS-related complex, and asymptomatic infected individuals at high risk for AIDS. The virus is transmitted by sexual contact, by exposure to infected blood or blood products, or from an infected mother to her fetus or infant. HIV type 2 infection is endemic only in West Africa, and it has been identified in individuals who had sexual relations with individuals from that geographic region. HIV-2 is similar to HIV-1 in viral morphology, overall genomic structure, and its ability to cause AIDS.
Antibodies against HIV-1 and HIV-2 are usually not detectable until 6 to 12 weeks following exposure and are almost always detectable by 12 months. They may fall to undetectable levels in the terminal stage of AIDS when the patient’s immune system is severely depressed.
Routine serologic screening of patients at risk for HIV-1 or HIV-2 infection usually begins with a HIV-1/-2 antigen and/or antibody screening test, which may be performed by various FDA-approved assay methods, including rapid HIV antibody tests, enzyme immunoassays, and chemiluminescent immunoassays. In testing algorithms that begin with these methods, supplemental or confirmatory testing should be requested only for specimens that are repeatedly reactive by these methods.
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The Meaning Of A Negative Hiv Test
One would imagine that an HIV test would be fairly cut and dry, with the results either being HIV negative or HIV positive. HIV negative means you have no signs of HIV in your blood; a positive HIV test means that you do have signs of HIV in your blood. You can be positive for HIV even if you don’t have symptoms.
But there is a scenario when a negative HIV test may not be all that it appears. When testing for HIV, there is a short window period;when a person can test negative and actually have the virus in his or her system.;
And the reasons are simple: when HIV infection occurs, a person’s immune system begins to develop specialized proteins called antibodies, which are specific to the individual pathogen it aims to neutralize .;It is those antibodies that most antibody-based HIV tests detect.
It takes some time for enough of those antibodies to be produced for an HIV test to detect them. Therefore, if too little HIV antibody has been produced when a person gets tested, the test result will be returned as negative despite the fact that an actual infection has occurred.
Dried Blood Spot Test
A DBS test is a free, accurate and convenient way to test for HIV in the comfort and privacy of your home.
It involves collecting a few drops of blood from your finger and allowing the blood to dry on a test card.;You then send the card away to get tested and wait around a week to get the result back. You can register for a DBS HIV test here.
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Understanding A Negative Result
What does a negative test result mean?
A negative result doesnt necessarily mean that you dont have HIV. This is due to the window period.
If you test again after the window period, have no possible HIV exposure during the window period, and the result comes back negative, you do not have HIV.
If you have certain risk factors, you should continue getting tested at least once a year. Learn more about who is at risk for HIV;and why they should be tested more often.
If I have a negative result, does that mean my partner is HIV-negative also?
No. Your HIV test result reveals only your HIV status.
HIV is not necessarily transmitted every time you have sex or share needles, syringes, or other drug injection equipment. And;the risk of getting HIV;varies depending on the type of exposure or behavior. It is important to remember that taking an HIV test is not a way to find out if your partner has HIV.
Its important to be open with your partners and ask them to tell you their HIV status. But keep in mind that your partners may not know or may be wrong about their status, and some may not tell you if they have HIV even if they are aware of their status. Consider getting tested together so you can both know your HIV status and take steps to keep yourselves healthy.
What Does Non Reactive Test Results Mean
Test hiv 4th generation on 24 july antibody/antigen- non reactive , This suggests that you have not been exposed to COVID-19, which is definitely what you want to hear, No evidence of active Hep B infection Ive never seen that bolded part before when I got tested for Hep B in the past, No confirmatory neutralization assay required, 9.8K views.
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How Do I Get My Results
Depending on the type of test you take, you will have to wait either a few minutes for your results , or anywhere between a couple of days or weeks . Your healthcare professional should explain how you will get your test results. If you are self-testing, there will be information on how to read your results with your test kit.
If your result is negative, the health centre will contact you to let you know that you tested negative. All positive and will have to be checked again, so you will be asked to come back for further testing.If you get a positive result after using a self-test kit you will need to go to a healthcare clinic.;
What Does A Negative Result Mean
If your HIV test result comes back negative it means that the test hasnt found signs of HIV infection.
However, if you have been at risk since your last test then youll need to test again. Also remember that most HIV tests can only detect HIV one to three months after exposure. If you were at risk more recently than this you will need to test again to be sure that your results are accurate.
Using a;condom; is the best way to protect yourself from HIV.
Be aware that testing negative for HIV doesnt mean that your partners are HIV-negative. HIV tests only apply to the person who took the test. If any of your previous or current partners are worried about HIV, encourage them to take a test.
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Negative Hiv Test Accuracy
Some types of HIV tests will only look for antibodies. HIV testing done in a doctor’s office may also be able to detect HIV proteins produced by the virus, which can be detected sooner after exposure, shortening the window of detection.
Most physicians will recommend repeat testing three months after exposure to ensure one has a truly negative HIV test result. Some doctors will also recommend another HIV test six months after.
Newer testing assays, employing combination antibody/antigen detection, are far more accurate and sensitive than older generation antibody tests. These are more capable of detecting HIV during the early, acute stages of infection, shortening the window period by as much as a month.
These tests work by detecting the HIV-specific proteins called antigens, which initiate the immune response and are therefore produced more rapidly after infection than antibodies.
If all of the tests are negative, and a person has had no new HIV exposures, then they are considered to be HIV negative and clear of infection.
However, if a person has another possible exposure to the virus between tests , the tests will need to be repeated, starting over from the point of the new exposure.
Always speak with your healthcare provider about when you need to be tested and if retesting may be needed to provide greater confidence in the results.
How Long Do Results Take
Rapid HIV tests can give results in 15 to 60 minutes, or on the same day.
Rapid refers to the time taken for the results and not to the time between exposure and the test.
If samples are being sent to another lab, results can take from a few days or a few weeks.
Rapid blood tests put a pin-prick of blood on a testing strip. This test takes about 15 to 20 minutes so you can get the results whilst you wait.
Some rapid tests also work on oral samples rather than blood. Although they are sometimes called saliva tests this is not accurate. Oral samples collect cells from the surface of the gums and not saliva. These cells contain HIV antibodies.
When samples are sent to a lab you can either collect your results in person or they will be posted out to you. It is your responsibility to get the results. A few clinics may give results over the phone.
Rapid tests involve a 3 month window. This means the results tells you your HIV status three months ago. A positive result from a rapid test always needs to be confirmed by a different laboratory test. If you have had other recent risks, a negative result needs to be confirmed in three months.
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There Are Three Main Tests:
- Fourth Generation: The 4th generation test, is a type of blood test which takes about 3-5 days to get the results. This test is sensitive enough to detect HIV in your blood 2 weeks after a possible exposure. Offered almost everywhere.
- Rapid test :Both tests take about 20 minutes to get the results. This test will provide you with results 6 to 8 weeks after an exposure.
- Blood test is a finger stick; a small amount of blood is taken from the tip of the finger and mixed in a solution. There are both 4th and 3rd generation rapid tests.
- Oral test a small amount of saliva from a persons mouth is obtained using a cotton swab that looks like a toothbrush. You can buy this test at a pharmacy. We strongly encourage people to get tested in a clinic or at your primary care providers office for additional support and education.
If any preliminary test is positive, the NAT blood test is done to confirm that the person is HIV positive.
Its important to know there are three types of results that can come from a rapid test:;;invalid, non-reactive and;reactive.
The third and last part of testing is getting your results and talking about what those results mean for the future. No matter which test a person chooses to do, its very important to always get your results!
What Do Hiv Test Results Mean
If an HIV antibody test is negative, no antibodies were detected. A negative test can indicate that a person is not infected with HIV , or that s/he has been exposed but their immune system has not had time to produce antibodies. Antibodies to HIV may take up to six months to develop after the initial exposure.
A positive HIV antibody test means that the body has been exposed to HIV .; A person with a positive HIV test will need to have further testing done to confirm this diagnosis. When a person has a positive HIV test, it does not mean that the person has AIDS or that the person will have AIDS in a certain amount of time–it only means that the person is infected with HIV.
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