AIDS

Encyclopedia of Alternative Medicine, Apr 06, 2001 by Belinda Rowland

Acquired immune deficiency syndrome (AIDS) is an infectious disease caused by the human immunodeficiency virus (HIV). It was first recognized in the United States in 1981. AIDS is the advanced form of infection with the HIV virus, which may not cause disease for a long period after the initial exposure (latency). Infection with HIV weakens the immune system which makes infected persons susceptible to infection and cancer.

AIDS is considered one of the most devastating public health problems in recent history. In 1996, the Centers for Disease Control and Prevention (CDC) estimated that one million persons in the United States are HIV-positive, and 223,000 are living with AIDS. Of these patients, 44% are gay or bisexual men, 26% are heterosexual intravenous drug users, and 18% are women. In addition, approximately 1,000-2,000 children are born each year with HIV infection. The World Health Organization (WHO) estimates that 18 million adults and 1.5 million children worldwide were infected with HIV as of 1995 with the potential to produce about 4.5 million cases of AIDS. Most of these cases are in the developing countries of Asia and Africa.

AIDS can be transmitted in several ways. The risk factors for HIV transmission vary according to category:

• Sexual contact. Persons at greatest risk are those who do not practice safe sex, are not monogamous, participate in anal intercourse, and have sex with a partner with symptoms of advanced HIV infection and/or other sexually transmitted diseases (STDs). In the United States and Europe, most cases of sexually transmitted HIV infection have resulted from homosexual contact, whereas in Africa, the disease is spread primarily through sexual intercourse among heterosexuals.
• Transmission in pregnancy. High-risk mothers include women married to bisexual men or men who have an abnormal blood condition called hemophilia and require blood transfusions, intravenous drug users, and women living in neighborhoods with a high rate of HIV infection among heterosexuals. The chances of transmitting the disease to the child are higher in women in advanced stages of the disease. Breast feeding increases the risk of transmission by 10-20% and is not recommended. The use of zidovudine (AZT) during pregnancy and delivery, however, can decrease the risk of transmission to the baby.
• Exposure to contaminated blood or blood products. With the introduction of blood product screening in the mid-1980s, the incidence of HIV transmission in blood transfusions has dropped to 1 in 100,000.
• Needle sticks among health care professionals. Present studies indicate that the risk of HIV transmission by a needle stick is about 1 in 250. This rate can be decreased if the injured worker is given AZT or triple therapy (HAART) the current standard.

HIV is not transmitted by handshakes or other casual non-sexual contact, coughing or sneezing, or by bloodsucking insects such as mosquitoes.

AIDS in women is a serious public health concern. Women exposed to HIV infection through heterosexual contact are the most rapidly growing risk group in the United States. The percentage of AIDS cases diagnosed in women has risen from 7% in 1985 to 18% in 1996. For unknown reasons, women with AIDS do not live as long as men with AIDS.

Because AIDS can be transmitted from an infected mother to the child during pregnancy, during the birth process, or through breast milk, all infants born to HIV- positive mothers are at risk. As of 1997, it was estimated that 84% of HIV-positive women are of childbearing age; 41% of them are drug abusers. Between 15-30% of children born to HIV-positive women will be infected with the virus.

AIDS is one of the 10 leading causes of death in children between one and four years of age worldwide. The interval between exposure to HIV and the development of AIDS is shorter in children than in adults. Infants infected with HIV have a 20-30% chance of developing AIDS within a year and dying before age three. In the remainder, AIDS progresses more slowly; the average child patient survives to seven years of age. Some survive into early adolescence.

Because HIV destroys immune system cells, AIDS is a disease that can affect any of the body's major organ systems. HIV attacks the body through three disease processes: immunodeficiency, autoimmunity, and nervous system dysfunction.

Immunodeficiency describes the condition in which the body's immune response is damaged, weakened, or is not functioning properly. In AIDS, immunodeficiency results from the way that the virus binds to a protein called CD4, which is found on certain white blood cells, including helper T cells, macrophages, and monocytes. Once HIV attaches to an immune system cell, it can replicate within the cell and kill the cell. In addition to killing some lymphocytes directly, the AIDS virus disrupts the functioning of other CD4 cells. Because the immune system cells are destroyed, infections and cancers that take advantage of a person's weakened immune system (opportunistic) can develop.