HIV test

HIV is known not to cause any complaints in most cases and it may often replicate undisturbed in your body for years and slowly destroy the cells of your immune system. The only way to know whether or not you have been infected is to get tested.

With the slightest of doubts you should always get tested; this will allow you to start antiviral treatment as soon as possible, if necessary, and to keep the HIV under control and live a full life.

Who should get tested for HIV?

Taking an HIV test is as normal as getting a routine check-up. All sexually active people should get tested for HIV at least once in their lives.

Be sure to definitely get tested for HIV if:

You have had unprotected sex;
You have a history of multiple sex partners;
You have used other people’s syringes or needles;
You were injured while working or you were exposed to someone else’s blood in the event of an accident;
You are pregnant; or
You have sexually transmitted infections, hepatitis B or C and/or tuberculosis.

You should get tested for HIV if you have exhibited risk behaviour and you:

Have lost a lot of weight and there is no explanation for it;
Are constantly feeling tired and weak;
Have run a slight fever for weeks;
Have had diarrhoea for weeks;
Have night sweats;
Have a dry cough not caused by smoking, bronchitis or pneumonia; or
Have swollen lymph nodes on your neck or in your armpits and/or groin.

The above symptoms may indicate other diseases as well and they may not mean that you have HIV. At the same time some people may suffer from HIV without any symptoms at all.

Any doctor can order an HIV test. An HIV test is called for with certain indicator diseases and indicator conditions.

How often should you get tested for HIV?

In the event of risk behaviour you should get tested for HIV at least once a year. One test is enough if you have stopped your risk behaviour and have not been exposed to any HIV infected blood after having tested negative for HIV.

Taking an HIV test is easy

A blood sample for an HIV test and associated counselling is free of charge for everybody, regardless of their health insurance status.
The procedure itself is relatively easy and painless. Depending on the type of test, blood will be drawn from either the vein or fingertip.
An appointment need not be made for getting tested for HIV at a counselling and testing clinic.
A blood test and counselling will take about 15 minutes.

HIV tests are confidential

HIV tests and counselling take place in private. You can do this completely anonymously at HIV testing and counselling clinics. Your name or other personal data will not be required. Getting tested for HIV at youth counselling centres is not anonymous but the only persons who will know your test results are you and the doctor.

What does an HIV test show?

An HIV test shows whether or not you have been infected with HIV. The presence of HIV in a person’s body can be determined by testing their blood. The immune system of someone with HIV produces antiviral antibodies that a healthy person does not have. Depending on the type of test, it is tested whether there are anti-HIV antibodies (HIV-1 and HIV-2 and IgM and IgG antibodies) and/or HIV proteins in the blood.

What is the window period?

The window period is a period of time after the passing of which HIV can be detected in the human body. The length of the window period depends on the manner of identification of HIV, meaning on the type of the test.

For example, for laboratory diagnosis of HIV by immunoassay, virus elements and antibodies in the blood are identified; the window period is 3 to 4 weeks. A rapid test only shows anti-HIV antibodies and the window period is 10 to 12 weeks.

In the event of risk behaviour and suspicion of having contracted HIV, don’t wait but make sure to get tested. If your test result is negative, make sure you are not in the window period. Based on the length of the window period of your test take another test after the passing of the required period of time.

Types of HIV tests

1. Laboratory diagnosis of HIV

Blood from the vein is analysed
Window period is 3 to 4 weeks
HIV-1 and HIV-2 antibodies and HIV antigen (p24) are determined
Test accuracy > 99%
Test result within three business days

2. Rapid test

Finger prick blood test or venous blood test
Window period is 10 to 12 weeks
HIV-1 and HIV-2 antibodies are determined
Test accuracy 95–99%
Test result within 1–2 minutes

3. HIV RNA detection

HIV RNA detection by polymerase chain reaction (PCR) is used for diagnosing newborns with HIV. In HIV RNA detection the window period is about 1–2 weeks.

Saliva tests can also be used for HIV testing. Since saliva tests are not as accurate as blood analyses, these are hardly ever performed in Estonia.

HIV test result

The initial test result may be negative, positive or indeterminate.

Negative test result

A negative test result means that you don’t have HIV. In the event of risk behaviour and if you suspect having HIV, make sure you are out of the window period and get re-tested after the window period. With specific exposure to HIV, the final negative result based on detection of antibodies may be confirmed after six months.

Indeterminate test result

An indeterminate test result requires confirmation from HIV reference laboratory. If the confirmation test also produces an indeterminate result, the analysis must be repeated.

Possible reasons for an indeterminate result: autoimmune disease, cystic fibrosis, pregnancy, blood or blood component transfusion, liver diseases, recent vaccination, the seroconversion stage or the final stage of HIV.

Positive test result

A positive test result means that you are infected with HIV. Every initial positive result is checked at a reference laboratory for HIV using a more precise method; in other words a confirmation test is made. In single instances an initial positive result may prove to be false positive. A positive result may be produced, for example, after an acute viral disease or in the event of a systemic disease.

Confirmation test

A confirmation test always uses blood from the vein regardless of the type of the initial test. HIV is diagnosed only by a positive test result confirmed by a reference laboratory.

The reference laboratory for HIV first informs of the confirmation test result your doctor who administered the test. You will find out the result of the analysis from your doctor who will refer you to an infectious disease doctor who will prescribe anti-HIV treatment. If you got tested anonymously and the test result came back positive, the confirmation test is only available in personalised form. By law, the diagnosis will also be registered in the communicable diseases information system maintained by the Health Board.

Be sure to tell your partners with whom you have had sex and/or shared needles and syringes that you have HIV. They have to know that they have been exposed to HIV and may be infected, too.

What will you gain from knowing your HIV test result?

A negative HIV test result will give you a sense of security. If your HIV test result is positive, you will have the chance to start treatment as soon as possible, allowing you to continue living a full life.