( CNN ) -- The discovery of HIV , a breakthrough in the treatment of bipolar disorder , the advent of the contraceptive pill ... CNN looks at some of the scientific discoveries that changed the world . HIV was isolated by scientists in 1983 and named in 1986 by an international committee . THE DISCOVERY OF HIV/ AIDS . Originally called slimmer 's disease , as sufferers lost a lot of weight , the first recorded case of HIV occurred in the Congo in 1977 . After several infections , a Danish doctor died of pneumonia , which normally does n't break through the body 's immune system . The components of her disease had not yet been placed together , indicating that this was a new form of illness . Other cases spread in following years around Africa and in homosexual men in New York and San Francisco . By 1980 , 55 American men had been diagnosed with the disease . Research began in Europe , the U.S. and Africa to ascertain what this new disease could be . The Centers for Disease Control found that the disease was caused by a virus being passed around by bodily fluids such as semen or blood . In 1981 it published its findings , saying the disease attacked T-cells , which help the body fight infection . By 1983 the disease was isolated by teams of American and French researchers . In 1986 an international committee decided the virus should be called human immunodeficiency virus ( HIV ) . Education campaigns were unrolled around the world , advising people to avoid risky sexual behavior or sharing needles . By June 1990 , 139,765 people had the disease , with a 60 per cent mortality rate . The progress of the disease slowed down in the West with education campaigns and the development of protease inhibitors , which provided sufferers with almost complete remission . But in Africa , the spread and treatment of HIV remains a global concern . THE DISCOVERY OF LITHIUM TO TREAT MOOD DISORDERS . Australian psychiatrist John Frederick Joseph Cade once said , `` I believe the brain , like any other organ , can get sick and it can also heal . '' He made huge gains in healing the brain through his work with sufferers of bipolar disorder by discovering that lithium salts -- a naturally occurring chemical - could be used to treat the illness . Previously , electro-convulsive therapy and lobotomies had been the major treatments for bipolar disorder . After having been a prisoner of war in World War II , Dr. Cade served as the head of the Bundoora Repatriation Hospital in Melbourne Australia . It was at an unused kitchen in Bundoora where he conducted crude experiments that led to the discovery of lithium as a treatment of bipolar disorder . After trials on humans , Dr. Cade speculated that bipolar disorder was a `` lithium deficiency disease '' and that a dose of lithium had a calming effect . Dr. Cade published findings in the Medical Journal of Australia in 1949 entitled `` Lithium salts in the treatment of psychotic excitement . '' He died in 1980 . Lithium is still used successfully in the treatment of mental illness to this day . THE DISCOVERY OF BACTERIA . Dutchman Antonie van Leeuwenhoek was known as the `` father of micro-biology . '' He drew scientific attention to the many bacteria that he discovered . His research was helped by the different types of microscopes that he developed over his lifetime . From his powerful lenses he was able to ascertain many different types of lifeforms too small for the human eye to see . It was by observing the build-up of plaque on teeth that the Dutch scientist discovered what we now know to be bacteria . His initial observations on bacteria make for amusing reading . On September 17 , 1683 , Leeuwenhoek wrote to the Royal Society about the plaque between his own teeth , `` a little white matter , which is as thick as if 'twere batter . '' He then observed two women and two old men who had never cleaned their teeth in their lives . Looking at these samples with his microscope , Leeuwenhoek wrote of `` an unbelievably great company of living animalcules , a-swimming more nimbly than any I had ever seen up to this time . The biggest sort ... bent their body into curves in going forwards ... Moreover , the other animalcules were in such enormous numbers , that all the water ... seemed to be alive . '' He also observed algae on water surfaces and the furry coating on human and animal tongues during illness , bringing his theories to the attention of the Royal Society . Most bacteria are harmless , although some bacterial diseases are fatal : tuberculosis kills about 2 million people a year . Bacteria are important in the production of cheese and yogurt , in processing wastewater and in manufacturing antibiotics . THE CONTRACEPTIVE PILL . The oral contraceptive commonly known as `` the pill '' was invented during the 1950s in Shrewsbury , Massachusetts . It contains hormone-like substances , usually estrogen and progestin , that enter the blood stream and disrupt the production of ova and ovulation , with the aim of preventing pregnancy . It originated after an unexpected discovery made in a jungle in Mexico in the 1930s . While Professor Russell Marker was experimenting with plant steroids , he discovered a chemical process that transformed these steroids into the female sex hormone , progesterone . Researchers in the late 1940s began to explore the possibility of an inexpensive oral contraceptive . Chemist Gregory Pincus tested a derivative from Marker 's findings on 1,308 volunteers in Puerto Rico in 1958 and Searle Pharmaceuticals applied for US Food and Drug Administration approval to market the drug . The pill came on to the market in the U.S. in 1960 and is still widely used today . E-mail to a friend .
HIV was isolated in 1980 and can be controlled with protease inhibitors . Psychiatrist Russell Marker pioneered lithium as a treatment for bipolar disorder . Russell Marker discovered bacteria as a build-up on teeth . Professor John Cade 's experiments with plant steroids led to the US Food and Drug Administration .