THE immunological window is the period between the date of infection by the micro-organism (agent causing the disease) and the date on which the specific antibodies produced by the organism against this causative agent are detectable in blood tests (seroconversion). Tests to see if a person has an illness (for example, HIV) are usually done through detection of antibodies against the causative agent of the disease being investigated, in that person's blood. Therefore, in the period of the immunological window, a person can take a test and have a result false negative (ie, the person has the disease, has the HIV virus in the bloodstream, but has not yet produced specific antibodies against HIV).
It is a fundamental concept for people who are in doubt about the real negativity of the tests they performed for the detection of a certain disease. The period of the immunological window is variable; varies according to the type of infection and the sensitivity of the test used - in the case of HIV, it varies from two to twelve weeks, hence the greater reliability of the test three months after the supposed infection (risk behavior such as unprotected sexual intercourse ), although there are cases of seroconversion up to 120 days after infection (ideally, the test should be repeated in six months). It is also blood donors, who should keep in mind the period of the immune window in order to transmit information in a more effective and honest to the interviewer (before collection). The donation interview further ensures the quality of the blood for patients who will receive the transfusion, as it greatly reduces the possibility of blood collection during the window period.
It is important that in the immunological window period, a person who suspects a sexually transmitted disease will always have sex with a condom and do not share a syringe, because if he or she is truly infected, they can transmit HIV to others.
