HIV (the human immunodeficiency virus) is the viral cause of the syndrome known as AIDS (acquired immunodeficiency syndrome). Although everyone who develops AIDS is HIV-positive, not everyone is HIV-positive has developed AIDS.
Infection
Acute HIV infection is the first stage of HIV infection. During this time, the body develops antibodies against the virus. Developing a detectable level of these antibodies (seroconversion) is the first point at which an infected person will test positive for HIV and occurs 1 to 6 months after infection.
Effects
HIV targets the cells (lymphocytes) of the immune system, in particular CD4+ cells. As these cells are infected, they reproduce viral particles instead of copies of themselves because HIV has changed their genetic code.
Latency
Latency is the phase during which an HIV-positive person experiences no symptoms. Although there are no evident symptoms, HIV is continuing to replicate within the body and the virus can still be transmitted to others.
AIDS
AIDS is diagnosed in HIV-positive persons when CD4+ cell counts drop below 200 per milliliter of blood, when CD4+ cells are less than 14 percent of lymphocytes, or when an AIDS-defining illness, such as thrush, Pneumocystis pneumonia, or Kaposi's sarcoma appears (see link in References).
Treatment
A group of drugs known as antiretrovirals are used to target different facets of HIV infection. They are most commonly taken as a group, a therapy called HAART (highly active antiretroviral therapy); HAART may delay the onset of AIDS in HIV-positive persons.
Considerations
HIV is a virus, while AIDS is a syndrome, which means a series of conditions. AIDS-defining illnesses occur in HIV-positive people only when the virus has depleted the immune response.
Tags: AIDS HIV-positive, HIV-positive persons