In a clinical trial, the group of participants that is not given the experimental intervention being studied. The control arm can receive an intervention that is considered effective (the standard), a placebo, or no intervention. Outcomes in the control arm are compared with those in the experimental arm to determine any differences, for example, i [..]

When an HIV-infected mother passes HIV to her infant during pregnancy, labor and delivery, or breastfeeding (through breast milk). Antiretroviral (ARV) drugs are given to HIV-infected women during pregnancy and to their infants after birth to reduce the risk of mother-to-child transmission (MTCT) of HIV. ARV drugs also protect the health of HIV-inf [..]

The bullet-shaped center of HIV. The HIV capsid contains the genetic information (two single strands of RNA) and three enzymes needed for HIV to replicate. See Related Term(s): Envelope, Enzyme, Glycoprotein, Human Immunodeficiency Virus, Ribonucleic Acid Image(s): (Click to enlarge)

When a particular treatment or procedure should not be used under any circumstance because of the severe and potentially life-threatening risks involved. See Related Term(s): AIDS Case Definition, AIDS Dementia Complex, Contraindication, Relative Contraindication

A skin disorder characterized by velvety, light brown-to-black markings that develop mainly in the folds of the body, such as in the armpits, groin, and creases of the neck. Acanthosis nigricans can be an inherited condition or can occur as the result of an endocrine disorder, cancer, or use of certain medications.

Immunity that develops during a person’s lifetime. There are two types of acquired immunity: active immunity and passive immunity. See Related Term(s): Active Immunity, Immunity, Passive Immunity

A disease of the immune system due to infection with HIV. HIV destroys the CD4 T lymphocytes (CD4 cells) of the immune system, leaving the body vulnerable to life-threatening infections and cancers. Acquired immunodeficiency syndrome (AIDS) is the most advanced stage of HIV infection. To be diagnosed with AIDS, a person with HIV must have an AIDS-d [..]

Immunity that develops after exposure to a disease-causing infectious microorganism or other foreign substance, such as following infection or vaccination. See Related Term(s): Acquired Immunity, Passive Immunity

A federally funded research program that studies how HIV infects humans and how the disease progresses to AIDS.

Flu-like symptoms of acute HIV infection that may appear approximately 1 to 4 weeks after infection. Symptoms such as fever, headache, fatigue, and swollen lymph nodes can last from 1 to 4 weeks, and then subside. During the acute stage of HIV infection, many, but not all, people will have symptoms of acute retroviral syndrome. See Related Term(s): [..]