HIV and AIDS

Acquired Immunodeficiency Diseases

• Result from various causes, including severe stress, malnutrition, and environmental factors.
• Acquired immunodeficiency syndrome (AIDS) is a type of immunodeficiency disease caused by human immunodeficiency virus (HIV).
• AIDS is defined as certain opportunistic or rare infections along with infection by HIV or a severe decrease in the number of helper T cells and a positive test for HIV.

AIDS Signs and Symptoms

• AIDS is not a disease but a syndrome.
• Several infections and diseases define AIDS.
• Examples of diseases associated with AIDS include Kaposi's sarcoma and disseminated herpes.

AIDS Pathogen and Its Virulence Factors

• HIV is an enveloped, +ssRNA virus and a retrovirus.
• HIV uses reverse transcriptase to make a DNA copy of its genome.
• There are two major types of HIV: HIV-1, prevalent in the United States and Europe, and HIV-2, prevalent in West Africa.

HIV Transmission and Early Life Cycle

• HIV is transmitted when infected blood, semen, vaginal secretions, or breast milk come in contact with an uninfected person's mucous membranes.
• Viral protein gp120 facilitates attachment to a host immune cell with CD4.
• Viral protein gp41 promotes fusion of the viral envelope to the target cell.
• Reverse transcriptase transcribes dsDNA from ssRNA, and errors introduced during transcription result in antigenic variants of HIV.

HIV Replication Cycle

• dsDNA provirus enters the nucleus and is integrated into a human chromosome by viral integrase.
• Integrated DNA is passed to progeny cells during replication.
• Provirus can remain dormant for years, and macrophages and monocytes are major reservoirs of HIV.

HIV History and Origin

• HIV-1 was discovered in 1981 by Gallo and Montagnier, and subsequently, HIV-2 was isolated in West Africa.
• HIV likely arose from a mutation of simian immunodeficiency virus and may have emerged in the human population around 1930.

Pathogenesis of AIDS

• Only humans can replicate HIV.
• HIV destroys the immune system by destroying helper T cells, which relates to the course of AIDS.

This quiz covers the causes and effects of acquired immunodeficiency diseases, including severe stress, malnutrition, and AIDS. It explores how these factors impact the immune system and cell production.