Acquired immunodeficiency syndrome or Acquired immune deficiency syndrome (AIDS) is a disease caused by a virus called HIV. Acquired means that people are not born with the disease. They get it after being infected with the HIV virus. Immune or Immuno- talks about the immune system. The immune system is the part of the body that fights off disease. Deficiency means not to be enough. An immuno-deficiency is a problem where the immune system is damaged and cannot fight off diseases to keep the body healthy. Syndrome is a collection of symptoms, or problems in the body. Because the immune system is damaged, and cannot fight off disease, people with AIDS get a collection of symptoms which is referred to as the "Acquired Immunodeficiency Syndrome."
How many people have AIDS? As of 2018, it is estimated that there are 39.7 million people worldwide infected with HIV. The HIV pandemic is most severe in Sub-Saharan Africa. Over 60% of all people with HIV live in the region.
Many people with HIV do not know they have it. Because of this, the exact number of people with HIV is unknown.
Where HIV started
Scientists believe the first human who got HIV was a person in Africa in the early 1900s. It infected only a small amount of people (disease not recognised), until it then turned into an epidemic reported to have started in New York (USA) in 1981. It then very quickly started spreading to other countries. This happened when Simian Immunodeficiency Virus (SIV) went from apes or chimpanzees to humans. This virus probably crossed to humans when a hunter came into contact with monkey blood while cutting up monkeys to eat. Research in October 2014 shows that the virus started in Kinshasa during the 1920s. It was quickly spread by unprotected sex, dirty needles used by intravenous drug users, and it then made its way into the medical blood supply . Some people described the spread of the disease as a sexidemic (widespread).
HIV and AIDS
Not everyone who has HIV has AIDS. When people first get HIV, they can be healthy for years. A person is diagnosed as having AIDS when he or she gets specific types of illnesses or gets sick in certain ways due to their HIV. Once a person's HIV progresses to (or turns into) AIDS, the person will continue to have AIDS for the rest of their life. While there are many treatments for HIV/AIDS, at this point there is no cure.
If someone has HIV they are called HIV-positive.
Someone has AIDS if they have HIV and either: Blood tests that show very low numbers of white blood cells – special cells that fight infections AIDS defining illnesses (illness is another word for disease.)
AIDS-defining illnesses
If a person gets an "AIDS-defining illness," this is usually a sign that the person has AIDS. Healthy people do not get these illnesses, because a healthy immune system is strong enough to fight off these diseases. Because of this, getting an AIDS-defining illness is a sign that a person's immune system is seriously damaged. In a person with HIV, getting an AIDS-defining illness signals that the HIV has damaged the immune system badly enough that the person now has AIDS.
Some AIDS defining illnesses are: Kaposi's sarcoma – a type of cancer that usually affects the skin (often causing red or purple lesions, or wounds, on the skin). Sometimes KS only affects the skin; sometimes it also affects other systems in the body. CMV retinitis – a virus that infects the back of the eye. Pneumocystis carinii pneumonia (acronym PCP) – a type of pneumonia, an infectious disease of the lung. PCP is the most common infection in AIDS patients. Toxoplasmosis – a parasitic disease (a disease caused by a parasite), which can cause problems in the brain as well as other systems in the body. Invasive cervical cancer – cancer of the bottom part of a woman's uterus. Invasive means the cancer has spread.
How is HIV spread? HIV can be spread by some body fluids that have HIV in them: Blood Semen Fluids from a woman's vagina Fluids from the rectum Breast milk From infected mother to child during pregnancy (Transplacental). This means a person can get HIV by: Having sex with a person with HIV without using condoms or other types of protection This includes anal sex and (sometimes) oral sex Sharing needles with someone who has HIV (to inject illegal drugs like heroin) Getting stuck with a needle that has been used on someone with HIV (this happens sometimes to healthcare workers like doctors and nurses) A mother with HIV can pass HIV on to her baby while she is pregnant or if she breast-feeds the baby
