It takes about 2 to 12 weeks for HIV to enter the body and replicate heavily. Once HIV enters the body, the virus can be detected in about 5 days. In about 14 days, some patients may experience symptoms similar to upper respiratory tract infections, which are in fact the acute symptoms of AIDS. At this time, HIV replicates in large quantities in the body and specific antibodies are produced in about 2 to 12 weeks. The period of time from when HIV enters the body until antibodies are detected in the body is called the window period of AIDS. The window period varies from person to person, from a relatively short window period of about two weeks for blood-borne HIV to three months for sexually transmitted HIV. Once diagnosed with HIV, patients are advised to use appropriate medication under the guidance of a doctor.