HIV is the acronym for human immunodeficiency virus which is responsible for the development of AIDS after prolonged HIV infection.
AIDS is Acquired Immune Deficiency Syndrome which develops in the latter stages of HIV infection.
HIV & Immunity
HIV is the virus, which is transmitted from person to person and is the causative microbe responsible for HIV infection. The virus targets the body’s immune cells. AIDS is the syndrome that results once the immune system has been significantly compromised and is unable to maintain adequate functioning.
Immunity in the human body is a complex system comprised of cells and chemicals. In conditions like HIV/AIDS, the virus targets a specific type of immune cell known as the CD4 T-lymphocyte. The virus enters and replicates within the cell and exits the immune cell thereby destroying it. As the disease progresses, the body’s immune functioning is hampered due to the decreasing immune cell population (test : CD4 count) in relation to the increasing viral population (test : viral load) and the patient is considered to be immunocompromised.
HIV infection does not indicate the onset of AIDS. Acquired immune deficiency syndrome is determined by the presence of AIDS defining illnesses or a CD4 count less than 200 cells/mm.
Common Names for HIV/AIDS
There are many common names for HIV/AIDS which varies among different cultures, languages and regions in the world. Example : isandulela ngculazi is the Zulu word for AIDS, widely used in South Africa which has the highest HIV/AIDS adult prevalence rate. HIV/AIDS is a global problem affecting every sector of the human population and the disease is perceived differently based on ignorance, misconceptions and cultural and religious beliefs.
The most common names for HIV/AIDS refers to the wasting (cachexia) which typically occurs in the latter stages of the disease. This is often referred to as the ‘thins‘ or ‘slim’s disease‘, a term very often used in Africa in the native tongue. Less politically correct names had emerged in the 1980s and early 1990’s at a time when the disease was only associated with gay men and homosexual behavior. These misconceptions have been allayed in recent years as HIV is more often spread in heterosexual couples.
Other terms for HIV/AIDS
- El sida (de SIDA, acrónimo de síndrome de inmunodeficiencia adquirida)
- El VIH (acrónimo de virus de inmunodeficiencia humana)
- VIH (virus d’immunodéficience humaine)
- SIDA (Syndrome d’Immuno Déficience Acquise)
Common Scientific Terms Related to HIV/AIDS
- ELISA or Western Blot are the two common blood tests utilized to detect for HIV infection. Both tests should be conducted to confirm the diagnosis if either test reveals a positive result. A positive ELISA test indicates the presence of HIV antibodies (immune proteins produced in response to the presence of the virus) in the blood. A Western Blot test detects HIV proteins in the blood to confirm diagnosis. If both are positive, the person can be diagnosed as HIV-positive meaning that they are infected with HIV. If negative, this indicates that HIV infection has not occurred or may be in an early stage where it cannot be detected in the blood (“window period”). Repeat testing is then required after 6 weeks to 3 months. A negative test is commonly termed as being “HIV negative” although this is not an accurate medical term for a person’s HIV status.
- ART or anti-retroviral therapy refers to the cocktail of antiviral drugs that are used in HIV infection, usually more than one type of antiretroviral (combination drug therapy). The individual drugs may be referred to as ARV’s or anti-retrovirals. The use of several antiviral drugs (combination therapy) to reduce the viral load may also be termed HAART (highly aggressive anti-retroviral therapy).
- CD4 count usually refers to the CD4 T-cell count which is an indication of the progression of the infection. HIV targets these T-lymphoctyes and over time, the CD4 cell population drops. This is usually in proportion to the increase of the viral copies within the blood (viral load). CD8 cell count or total lymphocyte count may also be taken into consideration to evaluate the difference between CD4 to total lymphocytes or CD4 to CD8.
- Viral load is a measure of the HIV nucleic acid (RNA) present in the infected person which increases as the disease progresses over time. It gives an indication of the progression of the disease, response to therapy and prognosis. Viral load together with the CD4 count are important in monitoring HIV infection and are deciding factors for the commencement of ART before the onset of AIDS.
- AIDS defining illnesses are those diseases or disorders that may be present in the latter stages of HIV infection. These diseases may also be present in patients who are not HIV positive but some are very rare conditions, yet often seen in HIV/AIDS.
- Candida infection of the mouth and/or esophagus
- Cryptococcal meningitis
- Cryptosporidium diarrhea
- Cytomegalovirus disease
- Dementia (AIDS Dementia)
- Encephalopathy (HIV-related)
- Herpes simplex (causing mouth ulcers and blisters)
- Herpes zoster (shingles)
- Kaposi’s sarcoma (KS)
- Mycobacterium avium complex
- Non-Hodgkin’s lymphoma
- Pneumocystis carinii pneumonia (PCP)
- Pneumonia (recurrent)
- Progressive multifocal leukoencephalopathy (PML)
- Salmonella septicemia (recurrent)
- Toxoplasmosis of the brain
- Wasting syndrome