HIV/AIDS: Etiology and Oral Manifestations

A person who tests for HIV will receive either a negative, positive, or indeterminate result. It is important to remember that a person could test negative for HIV antibodies, but could be recently infected.

The window period is the time it takes for an HIV-infected person to develop antibodies to HIV. Newer, more sensitive HIV tests have reduced the window period to 2-12 weeks. The CDC still advises individuals that the window period could last as long as six months. Standard advice for those considering HIV testing is to test three to six months after the last potential HIV exposure.

If you test before antibodies develop, you may need to be retested. Individuals who are testing because of occupational exposure may be told to test 12 months post-exposure.

People who are newly infected with HIV may have a large amount of virus in their blood. They are considered highly infectious for HIV. This means that an infected person may initially test negative for HIV antibodies but be more likely to be able to infect another person.

If the test result is negative, it means one of two things:

Either the person is not infected with the virus, or
The person became infected recently and is in the window period.

Most people take between 2-12 weeks after becoming infected to produce enough antibodies to show up on the test. In rare cases, it may take as long as 6 months. If a person got infected last night and goes for testing today, the test will not be able to detect antibodies for this particular exposure.

If a person gets a negative test result and is concerned about a possible recent infection, s/he should test again three to six months from the date of last possible exposure, and practice safer behaviors until s/he gets the result of the next test, as well as

A negative test result does NOT mean a person is immune to HIV. If risky behavior continues, infection may occur.

If the test result is reactive (positive), it shows the presence of HIV antibodies.

A positive test result means that:

A person is infected with HIV;
This person can spread the virus to others through unsafe sexual practices, sharing contaminated injection equipment and/or breastfeeding; and
The person is infected for life.

Occasionally, a Western Blot test result will come back with an "indeterminate" or "inconclusive" test result. If a person has recently engaged in behaviors that put them at risk for getting HIV, it could mean that they are newly- infected with HIV and are developing antibodies.

Indeterminate test results can also be caused by several factors, including but not limited to pregnancy, autoimmune diseases, blood transfusions, recent influenza vaccinations, or organ transplants.

Persons who receive indeterminate HIV test results should retest in one, three and six months, depending on their particular risk. Retesting is recommended even if HIV infection is extremely unlikely.

Studies have shown that only around 20% of people with indeterminate tests go on to become "truly" positive. There are people who may remain indeterminate throughout their lives - these cases are extremely rare.

The new drug therapies for HIV infection can sustain an infected person's health. Even if the HIV-positive person chooses not to start antiretroviral therapy, early detection of HIV will allow a person to receive medical treatment sooner, take better care of their immune system, and stay healthier longer. Additionally, early detection of HIV allows people to take precautions not to infect others.