HIV transmission and HIV testing
Do I have HIV?[+ show][- hide]
The only way for you to know this is to take an HIV test. Although websites can include information about different levels of risk, no website can answer whether or not you have HIV.
What is my risk for having caught HIV?[+ show][- hide]
HIV is mainly transmitted during sex and by sharing drug-using equipment. HIV enters the body in blood, semen, vaginal fluid or breast-milk from a person who has HIV. It is not transmitted by everyday contact. . HIV is not transmitted by saliva, sweat, tears, spit, urine or faeces. HIV is not transmitted by deep-kissing,body rubbing or contact with infectious fluid on skin. HIV is not spread by air or by insect bites
Testing for HIV is easy and usually free. If you are worried that you have been at risk, like millions of other people, take a test.
Do I need to take an HIV test?[+ show][- hide]
The only way you can know your HIV status by taking an HIV test. In the UK and most other countries, at least one-quarter of HIV-positive people do not know their HIV status.
Even if your exposure risk was low, you can only confirm whether you are HIV-positive or HIV-negative with a test.
HIV testing should be a routine part of looking after your sexual health. Repeating the test every 3-12 months – or depending on your sexual activity and risk – is advised.
Do I need to take a test if my partner just tested negative?[+ show][- hide]
- You can not use your partners test results to interpret your HIV status.
- You can only know if you have HIV by taking your own test.
- You could be HIV-positive and your partner has just been lucky so far. You need to know your status to protect your partner in the future.
- If your partner has just tested HIV-positive, you could still be HIV-negative, even if you have had unprotected sex. You need your own test results.
Can I ask another person to test?[+ show][- hide]
No. This is about your sexual health. It is your responsibility to test and take responsibility for your own health
When can I take a test?[+ show][- hide]
If you are worried about HIV, then you should take a test. If you have had a risk within the past 4 weeks, the test may need to be repeated. Your healthcare provider will advise you.
In the UK, guidelines say that 4th generation HIV tests (antigen/antibody) will detect more than 95% of infections 4 weeks after exposure. If you have had a high risk exposure, a negative result should be confirmed with a second test 8 weeks later. later. (Reference.)
In high risk exposures (ie needlestick injury by a health care worker with known HIV-positive person), especially if symptoms occur, then viral load testing is sometimes used after one week.
What is the window period?[+ show][- hide]
The window period is the term to describe the time between an exposure (risk) and the point at which an HIV test would show positive.
During the window period someone who is infected with HIV can have a HIV negative test result.
For newer 4th generation antigen/antibody tests this period is four weeks for the majority of infections. It could be as short as 1-3 weeks. Very occasionally, people take longer to develop antibodies and historically, a three month window is generally referred to. Recently updated UK guidelines reflect that most people will have a positive test result at 4weeks and state that the test should be repeated at 8weeks only if you have had a significant risk.
Your test results really tell you your HIV status 4weeks ago.
If you are worried, and if you have had further risks, repeat testing for HIV and other STIs is advised every 3-12 months.
Which test should I use?[+ show][- hide]
In the UK, a 4th generation antigen/antibody test, as discussed above,is most commonly used.. Sometimes, point of care tests for HIV (tests which give immediate results) have a 3 month window period so the result reflects your HIV status 3 months ago. Check with your healthcare provider how long the window period is, if you have a point of care test.
Information about different types of HIV test can be found here.
Where can I get an HIV test in the UK?[+ show][- hide]
I am worried about taking an HIV test…[+ show][- hide]
It is normal to worry whenever you take a test.
If it turns out that you are HIV-positive, then it is better for you to know this as early as possible. You can then access appropriate monitoring and treatment which will significantly improve your life expectancy.It will also help protect your sexual partners.
If it turns out that you are HIV-negative, then knowing this for certain will stop you worrying about this aspect of life.
An HIV test will focus you on your sexual health. If it is negative, use this experience to become aware of your sexual health in the future. Make regular HIV and STI testing part of looking after yourself and test every 3-12 months depending upon your level of risk.
How are results given?[+ show][- hide]
Your test centre should clearly explain the results of your test.
If you have questions that we not explained, or that still worry you, go back to ask that centre again.
Results are generally given as:
- Negative / non-reactive = HIV-negative = You do not have HIV (assuming you have not had any risks in the past 4 weeks)
- Positive / reactive = HIV-positive = You have HIV infection
- Indeterminate = the test results was unclear and will be checked with another test
Are HIV tests accurate?[+ show][- hide]
Yes. Modern HIV tests are very accurate within the time limits that they are recommended.
A 4th generation HIV test (antigen/antibody) will detect more than 95% of infections at 28 days after exposure. It will detect more than 99.99% of infections at three months.
False negative results (where the test shows negative but you are actually HIV-positive) are very rare from any blood test. They have been reported with some oral (saliva) tests if they are not given correctly. If you are worried about this, then a second test as advised by your healthcare provider would confirm your result.
A positive test result always needs to be routinely confirmed using a different type of test that is 100% accurate.
Does a negative result mean I do not have HIV?[+ show][- hide]
Yes if the test was four weeks after your exposure risk. This is the purpose to testing. If the result is negative, and you have not had another risk, you do not have HIV. Stop worrying. Learn from the experience you have gone through taking a test. Learn about how to protect yourself. Look after your sexual health in the future.
If you tested four weeks after the exposure, you a very likely to be HIV-negative, but you need to confirm the result with a second test eight weeks later. This is because a few people can take longer than 4 weeks to generate an immune response.
Is a negative result 100% accurate?[+ show][- hide]
We get asked this a lot. As an information service we have to say that technically, no test is 100% accurate.
This is partly to do with language. In science you can never prove 100% that something is NOT there or that something will NEVER happen. This is referred to as “the impossibility of proving a negative”.
In practice, a negative result four weeks after your last exposure risk is interpreted to mean you do NOT have HIV.
In real life, this means you do NOT have HIV.
If you have symptoms, this is not likely to be due to HIV. If they were related to HIV you would test positive. The symptoms are related to something else – see a doctor.
What is a ‘false negative’ test result?[+ show][- hide]
A false negative test result occurs when the test shows negative and the person is really HIV positive. This is very rare and usually occurs during the window period when people are newly infected but the test can’t pick up the infection. As with all diagnostic tests, there will always be a small margin of error. If you are worried you should have a second test. This will eliminate the possibility of a false negative result.
What is a ‘false positive’ test result?[+ show][- hide]
A false positive test is when the test result shows positive but the person is negative. This can happen with antibody tests when the test picks up antibodies for other infectious agents. Approximately 15 out of every 1000 antibody tests are a false positive. The fourth generation tests have a much lower chance of a false positive. This is why you should always have a second confirmatory test if the result is positive. The test used to confirm a positive result is 100% accurate. If the second test does not confirm you are positive then you do not have HIV.
Do I need to take another test?[+ show][- hide]
No, not if your exposure risk was more than four weeks prior to the test.
If you had a significant risk, then your test should be repeated at 8 weeks after exposure. This is what current UK and European guidelines say (Reference.)
Can anything affect the result of my HIV test?[+ show][- hide]
HIV antibody tests are not affected by other infections, medications, vaccinations, putting on weight, eating or drinking anything before the test, use of alcohol or recreational drugs, mouthwash or time of day.
Your test result is accurate even if you had flu or a cold or are using antihistamine treatment, for example, for hay fever.
You do not need to fast before your test, eating and drinking before the test will not affect the results.
What is the HIV self-test and can I take this at home?[+ show][- hide]
The first legally approved HIV self-test kit is now available in the UK. The self-test kit is currently provided outside of the NHS (developed by BioSure and costs £29.95) and provides a new option with the convenience of doing an HIV test at home and receiving the results outside of the clinical setting, which some people prefer. The test can be purchased from the BioSure website: http://hivselftest.co.uk/. If you decide to use the home testing kit and receive positive results it is important to seek medical advice as soon as possible to undergo a confirmatory HIV test and help you understand what this diagnosis means and the treatment options available.
How does the HIV self-test test work?[+ show][- hide]
The kit works by detecting antibodies – proteins that are made in response to the virus – from a small drop of blood (e.g. pricking your finger) and can provide results within 15 minutes. It is important to note that the kit only tests for HIV contracted after three months (providing 99.7% accuracy); therefore a negative result may be incorrect if you were exposed more recently and you should look to seek medical advice to ensure an accurate diagnosis.
What happens if my HIV self-test results are positive?[+ show][- hide]
Early diagnosis reduces the risk of passing the disease on to others and allows successful management of the disease. If you decide to use the home testing kit and receive positive results it is important to seek medical advice as soon as possible to undergo a confirmatory HIV test and help you understand what this diagnosis means and the treatment options available. If your test is negative it does not mean you are definitely not infected with HIV, especially if your exposure may have occurred within the past three months. If you engage in activities that increase your risk of exposure to HIV you should test regularly. This test is not suitable if you are receiving highly active anti-retroviral treatment (HAART).
How can my partner test positive and I test negative?[+ show][- hide]
See this Q&A.
What is seroconversion? What are the symptoms?[+ show][- hide]
Does this symptom [… rash/itch/headache etc.] relate to HIV?[+ show][- hide]
Most people worried about a recent infection mistake common symptoms of other illnesses with HIV. Stress and worry can cause and contribute to these symptoms.
Information about symptoms of recent HIV infection can be found here.
If you have any symptoms that are worrying you, then seek medical advice from a doctor or other health care worker. You cannot diagnose HIV or any other illness without taking a test.
Ways you can NOT catch HIV[+ show][- hide]
The following list includes examples or questions we get from people worried about catching HIV.
The information above should have clear enough these are not risks. Similar questions will not be answered in the Q&A pages but may just be added to this list below.
You can NOT catch HIV from:
- Sexual activity with someone who does not have HIV
- From a sterile needle at a GUM clinic or any other healthcare centre
- From a human bite
- From an insect bite including a mosquito bite
- From an animal
- From being in close proximity to a ’sharps’ bin in a GUM clinic
- From living in the same house as someone who is HIV positive (unless you have unprotected sex)
- From a sewing needle if you stab your finger
- Cleaning nail clippers
- Using a knife/fork/spoon/cup/plate etc
- From a plaster
- From a razor that hasn’t been used for hours (probably even minutes)
- From eating peanuts from a bowl
- Eating prepacked chicken which may have had human blood on it
- Eating any food cooked or uncooked with blood on it