What is HIV?

HIV is the Human Immunodeficiency Virus, a particular kind of retrovirus known as a lentivirus. What is HIV and how does it work? The virus works by attacking several of the cell types in humans that make up the body’s immune system. By lowering the immunity of patients this leads to opportunistic infections. It is usually these secondary infections that are noticed before a patient is tested for HIV and these are also what can make the patient seriously ill.

AIDS is a progression of HIV that can be defined in several ways. If the patient has tested positive for HIV and develops one of a list of opportunistic infections known to occur in AIDS patients then they are said to have AIDS. The patient is also defined as having AIDS if the count of CD4+ T-Helper cells in their blood drops below about 200 per mL as opposed to the normal level of 500-1500.

The name HIV was given to the virus in 1986, previous to which there were two other names it was known by. In the US the virus had been known as HTLV-III (Human T-Lymphotropic Virus III) and the name given to it in France was LAV (Lymphadenopathy-Associated Virus). The new name was given to prevent the confusion that arose due to the virus having more than one name.

HIV is now recognized as pandemic, meaning it is a worldwide problem not restricted to certain countries. It thrives in developing countries where treatments are either poor or unavailable and where the virus is known to kill people in as little as six months. In richer countries such as the US and parts of Europe, there are types of anti-retroviral treatments available that have been used successfully to prolong the lives of infected patients by up to 20 years.