2.1. Diagnostics and prevention
The HIV infection is distinguished by a long absence of symptoms. Diagnosis of the HIV infection is established through laboratory tests: by detecting antibodies to HIV. The first few weeks after the virus enters the body is the eclipse phase when HIV antibodies cannot be detected. On average, this period lasts from 3 weeks to 3 months, but there are a small percentage of people in whom this phase can last up to a year. The test results in this period can be negative, but this does not mean that the person does not have HIV, and it can be passed to other people, for example, through unprotected sexual contact. Therefore, one should repeat the test up to 3 months after probable exposure.
After the infection and incubation period, the acute phase of HIV infection starts, which may be accompanied by a variety of symptoms: fever, rash, increased lymph nodes and diarrhea. In most cases, an acute flu-like syndrome develops, which patients defined as being like a strong case of the flu. If there are such symptoms after the acute phase patients are also advised to take an HIV test. However, this stage can also be asymptomatic.
Currently there are two types of HIV diagnostic tests: indirect tests which allow for identification of antibodies to the virus, which almost 100% of people with HIV have; and direct tests that detect the virus (HIV RNA test) itself and proteins specific to the virus (gp120, gp41, p24, p17, p31, gp36, sgp105, sgp120).