Deterioration of intellectual faculties, often accompanied by emotional disturbance. HIV is active in the brain (central nervous system) and can cause dementia, even in those with high CD4 counts and low viral loads.

Mites that inhabit the skin and are usually found in the sebaceous glands and hair follicles. Although the mites are present and do not cause symptoms in most people, they may cause clusters of tiny bumps in immunosuppressed people.

Patrolling immune system cells that may begin the HIV disease process by carrying the virus from the site of the infection to the lymph nodes, where other immune cells become infected.

Deoxyribonucleic acid. A long molecule that in most organisms carries the genetic information in the form of a code. (See Gene).

An enzyme that can synthesise new complementary DNA strands using a DNA template and primer.