Antiretroviral Drugs/HAART These drugs represent a class of antiviral medicines designed to attack and inhibit different stages of retroviral infection and replication. When several of these drugs are used in combination to treat HIV (the Human Immunodeficiency Virus), this process is known as Highly Active Anti-Retroviral Therapy.
DNA Deoxyribonucleic acid provides the basic building block of all life on Earth. It takes the form of a polymer chain made up of nucleotides arranged in the form of a double helix, each side contains an identical code. Each organism’s DNA is linked together in the form of genes and chromosomes.
Human Genome Project Launched in 1990, this project sought to identify the location and function of the 3.3 billion base pairs of genetic data found within the human genetic code. Completed in 2003, the project has revolutionized our understanding of human diversity, disease and evolution.
Pandemic A pandemic refers to a disease epidemic that has infected a very large area – several countries, continents or the entire world. Examples include: the flu pandemic of 1918-19; the HIV pandemic that began in the 1980s; and the SARS pandemic of 2002-03.
SARS Probably originating in a disease hosted by wild animals such as civits, racoon dogs and bats, the virus causing the Severe Acute Respiratory Syndrome made the zoonotic jump to human populations in southern China in 2002 and then spread to 37 additional countries during the following year. Fatality rates for infected persons reached nearly 10 per cent.
Zoonosis Most diseases do not strike a single species. The process of a disease jumping from one species to another, particularly from animals to humans, is known as zoonosis. Sometimes, but not always, this transmission may require a mutation to take place in the infectious agent.
Influenza outbreaks have been a fact of human life for centuries, especially in temperate regions. Worldwide, flu kills tens of thousands of people annually. Between 1918 and 1920, however, a triple wave of particularly virulent influenza outbreaks killed tens of millions. One of the early outbreaks was in Fort Riley, Kansas, from where flu spread as troops were mobilized for combat in Europe. Wartime governments were hesitant to impose quarantines or issue health warnings for fear of undermining the war effort. Indeed, the name Spanish Flu reflected the fact that neutral Spain did not censor news of the flu. During spring 1918 the first wave of infections spread rapidly but were no more deadly than usual flu outbreaks. The following autumn and winter, however, a new, more deadly strain of the virus emerged – one that not only endangered the young and old but also, unusually, struck young adults. The 1918 outbreak was also unusual in that it spread to tropical regions where flu is rare. The demobilization of troops, many of whom had been drafted from European colonies in Africa and Asia, facilitated the spread of the outbreak. In the 1990s the 1918 pandemic was identified as an H1N1 variety of the flu.
This influenza pandemic killed more people in two years than did the infamous Bubonic Plague over many centuries.
Though it was named Spanish Flu, this catastrophic influenza epidemic’s exact origin has never been determined. The infection seems to have appeared almost simultaneously in North America, Europe and Asia. The spread of the disease was facilitated by the movement of troops and supplies during the First World War. Perhaps a third of the world’s population was infected. This particular influenza was unusually virulent: 3–5 per cent of the population – between 50 and 100 million people – perished.
RUPERT BLUE
1868–1948
American Surgeon-General during the outbreak
JOHN SYDNEY OXFORD
1942–
British virologist who has studied the 1918 flu epidemic
Jonathan T. Reynolds
The flu spread quickly among troops living at close quarters, men who were moved from country to country by the demands of the First World War.
In 1921 scientist Alexander Fleming accidentally discovered the antibacterial substance lysozyme when his runny nose dripped into a Petri dish of bacteria. A few years later, the world again benefitted from Fleming’s sloppy Petri dish handling. In 1928 Fleming went on holiday, leaving Petri dishes containing Staphylococcus aureus on his workbench. On his return, Fleming found that mould had contaminated several of the dishes. One of these moulds had killed the Staphylococcus bacterium. Upon further examination, the mould was found to be non-toxic and effective at killing a large variety of bacteria. It was not until 1940 that Howard Florey and Ernst Chain found a way to isolate the penicillin from the mould and produce it in a form useful to those who were ill. Mass production of penicillin quickly followed and the drug was sent to the battlefronts during the Second World War, saving countless lives from deadly infections. In the ensuing decades, the widespread use of antibiotics significantly reduced death and debilitation from sources ranging from small wounds to dental infections to sexually transmitted diseases. Perhaps only the eradication of smallpox compares as a triumph over illness in human history.
We all have Alexander Fleming’s sloppy handling of his Petri dishes to thank for one of the greatest medical discoveries of the modern age.
The most common cause of death in wartime was not bullets, but the resulting infections of the wounds they caused. Wartime conditions also increased the likelihood of diseases including influenza, cholera and typhus. With the discovery and mass-manufacture of penicillin, wounded soldiers were much more likely to survive the war and return to their families. The Allied forces in the Second World War saw these advantages and supported the production of penicillin as a war industry.
ALEXANDER FLEMING
1881–1955
Scottish bacteriologist and discoverer of penicillin
HOWARD FLOREY
1898–1968
Australian pharmacologist and pathologist who assisted in the production of useable penicillin
ERNST CHAIN
1906–79
German biochemist who assisted in the production of useable penicillin
Sara Patenaude
Fleming shared the 1945 Nobel Prize for Physiology with Howard Florey and Ernst Chain, who developed penicillin as a drug for wide use.
The term ‘double helix’ describes the three-dimensional structure of DNA (deoxyribonucleic acid), the molecule that encodes the genetic instructions found in the cells of all living things. The discovery of the double helix shape – like a ladder whose opposite ends are turned to twist the rungs into a sprial – helped unlock the basis of mutations (genetic changes) and replication (transmission of inherited characteristics) in the history of life. DNA was actually discovered in the 19th century by a Swiss researcher, Friedrich Miescher. For more than half a century other scientists struggled to imagine how the protein-coded DNA worked to take the information in the cell and transmit those instructions to make specific proteins. In 1953, Francis Crick, James Watson and Maurice Wilkins were credited with being the first to unlock the structural arrangement of DNA’s components or building blocks as linked pairs. They shared the Nobel Prize in 1962. Visualizing the structure of DNA enabled a generation of scientists to describe how genetics worked to pass information from parent to offspring and paved the way for the Humane Genome Project, which sought to sequence and map all the genes of the human body.
Although Crick and Watson did not discover DNA, their description of its double-helix structure has been heralded as the greatest scientific discovery of the 20th century.
Three men received the 1962 Nobel Prize for the discovery of DNA’s structure. The Nobel committee overlooked Rosalind Franklin, whose photographs led to the discovery of DNA’s shape. Her images of DNA molecules convinced Crick and Watson that their original structure was incorrect. Franklin’s article appeared in an issue of Nature immediately following Crick and Watson’s, the men were given ‘first place’.
FRANCIS CRICK
1916–2004
British physicist
MAURICE WILKINS
1916–2004
New Zealand-born physicist and molecular biologist
ROSALIND FRANKLIN
1920–58
Pioneer British molecular biologist
JAMES D. WATSON
1928–
American molecular biologist
Candice Goucher
Crick and Watson were helped by Franklin to visualize DNA’s spiralling double helix.
The term ‘birth control’ was first used in publication by Margaret Sanger in the June 1914 issue of her newsletter The Woman Rebel. At this time, birth control referred to methods of controlling pregnancy by timing sexual activity with a woman’s menstrual cycle or using barrier-type contraceptives such as condoms and diaphragms. Sanger, a nurse, advocated these methods while holding out hope for a ‘magic pill’ that women could take to prevent pregnancy safely. In her quest for such a pill, Sanger introduced scientist Gregory Pincus to philanthropist Katharine McCormick, who agreed to fund Pincus’s research into an oral contraceptive method. Alongside John Rock, Pincus created a medication with progesterone, a naturally occurring hormone that regulates ovulation. Women who take progesterone do not ovulate, and thus cannot become pregnant. After extensive clinical testing, the Food and Drug Adminisitration (FDA) approved use of the pill for women experiencing menstrual problems and, in 1960, extended approval for all women to use it as a contraceptive. By 1963, more than 2.3 million American women were taking the pill; a mere five years later the number of women using it jumped to more than 12 million worldwide even though it had been officially condemned by Pope Paul VI.
The pill made it safe and easy for women to take control of their fertility.
Oral contraceptive pills remained controversial even after FDA approval. Many states prohibited any sales of the pill, leading to the 1965 Supreme Court case of Griswold v. Connecticut, which determined that states could not prohibit the use of birth control by married couples. The 1972 Supreme Court case Eisenstadt v. Baird extended this protection to unmarried women. Both cases used arguments of Constitutional rights to privacy and free association to win their suits.
MARGARET SANGER
1879–1966
American activist and founder of the American Birth Control League
GREGORY PINCUS
1903–67
American biologist, inventor of the birth control pill
JOHN ROCK
1890–1984
American obstetrician and head of clinical trials for the birth control pill
KATHARINE MCCORMICK
1875–1967
American biologist and benefactor who funded the research into oral contraception
Sara Patenaude
Control over fertility revolutionized women’s influence over their private and professional lives.
Rosalind Franklin was a true innovator both in terms of science and of women working in what was traditionally a man’s field. Determined to become a scientist, Franklin attended Cambridge University, to study physical chemistry as it related to coal, a vital wartime resource. This was the subject of the thesis for her PhD, which she earned in 1945.
In 1944, Franklin took a job in a Parisian laboratory with crystallographer Jacques Méring. Méring taught her X-Ray diffraction, and soon she was able to capture images of single crystals and chemical molecules.
In 1947, Franklin accepted a post as research associate at King’s College London, working alongside Maurice Wilkins with the assistance of PhD student Raymond Gosling. At King’s she experienced workplace discrimination (for example, there was a men-only dining facility) and she and Wilkins often clashed. However, she worked diligently, fine-tuned her instruments, and, with the help of Gosling, captured a series of amazing photos of DNA, including one nicknamed Photo 51, which has been described as the most important photograph ever taken. She also tested the reactions of DNA fibres to various conditions, which aided her study of the structure of DNA.
In January 1953, Wilkins, without Franklin’s knowledge, selected what is now her most famous photograph and showed it to his friend, American geneticist James Watson. Seeing Photo 51, a striped, cross-shape, enabled him to understand that DNA has a double-helix structure. Watson returned to his partner, Francis Crick, at Cambridge with the image, and their now-famous model of DNA was published two months later. Today we realize just how much influence Franklin had on the Watson-Crick model. Watson attended a 1951 lecture by Franklin in which she discussed two forms of DNA, form A and B, the latter of which was a helix; by 1953, she had concluded that both forms were double helices with backbones on the outside. Watson and Crick had many discussions with Franklin’s lab partner, Wilkins, resulting in unauthorized access to information, such as Photo 51.
Franklin left King’s College for Birkbeck College in 1953 to study the structure of RNA and viruses. She undertook a great deal of research on the tobacco mosaic virus and began work on the polio virus, but had grown ill and was diagnosed with ovarian cancer. On 16 April 1958 Rosalind Franklin died; she was 37.
In 1962, Crick, Watson and Wilkins received the Nobel Prize in Physiology or Medicine for their work on the DNA model. It remains one of the most controversial Nobel Prizes awarded because its recipients excluded Rosalind Franklin. Technically, Franklin was not eligible, having died four years earlier; the Nobel Prize is not given posthumously. Only in recent years has the scope of her contribution been recognized.
Kristin Hornsby
Born in London, to a well-to-do family
1931
Attends St Paul’s Girl’s School, London, and shows talent for chemistry and physics
1938–1941
Studies chemistry at Newnham College, Cambridge
1941
Awarded research scholarship to work on gas chromatography
1942–45
Gives up the scholarship to work instead on the microstructure of coal for the British Coal Utilisation Research Association, work that gains her a PhD from Cambridge
1947
Takes job in Paris, learning techniques of X-ray diffraction
1951
Takes research associate position at King’s College, London, studying the structure of deoxyribonucleic acid (DNA) alongside Maurice Wilkins and Raymond Gosling
May 1952
Captures what is now known as Photo 51
1953
Crick and Watson publish their DNA model
1953
Franklin takes job at Birkbeck College to study the structure of ribonucleic acid (RNA)
1956
Cancer is diagnosed
16 April 1958
Dies in London from ovarian cancer
1962
Francis Crick, James Watson and Maurice Wilkins awarded the Nobel Prize for their work on the DNA model
Smallpox was an unusually virulent infectious disease. Easily transmitted by physical or airborne contact, the virus caused puss-filled blisters, high fevers and intense aches and pains. Around 30 per cent of adults and 80 per cent of children infected died. Survivors were often terribly scarred. Outbreaks routinely produced plague-like panics that helped to spread the disease. Vaccination techniques were independently developed in several world regions, but widespread inoculation did not begin until the 1800s. By the 1950s, global deaths had been cut to a still staggering 2 million annually. Efforts to eradicate the disease began in 1956 and were expanded in 1966 with the creation of the Smallpox Eradication Unit, involving health specialists from around the world. The project developed a system to identify and isolate outbreaks as quickly as possible. The last European outbreak of smallpox occurred in Yugoslavia in 1972, with isolated instances of the disease in India and east Africa in 1975 and 1977. The last death from smallpox occurred after a lab incident in Birmingham, UK, in 1978. In 1980, the WHO declared smallpox eradicated. Despite calls for the destruction of lab samples of the disease, the United States and Russia have refused to eliminate all specimens under their control.
The eradication of smallpox through an international campaign running from 1956 to 1980 is perhaps the greatest achievement of the 20th century.
Smallpox may have been the greatest infectious killer in history. Outbreaks occurred in Ancient Egypt, and by the 16th century it routinely killed 10–15 per cent of every generation. As late as the 1960s, it killed an estimated 2 million people per year, and perhaps as many as 500 million over the course of the 20th century. In 1956 the World Health Organization launched a campaign to eliminate the disease. By 1980 smallpox was declared eradicated.
FRANK JOHN FENNER
1914–2010
Australian microbiologist who chaired the Global Commission for the Certification of Smallpox Eradication
JANET PARKER
1938–78
British medical photographer and last person known to have died of smallpox
Jonathan T. Reynolds
Smallpox caused a very unsightly rash with blisters and in some cases led to blindness caused by scarring of the cornea.
HIV (Human Immunodeficiency Virus) causes AIDS (Acquired Immunodeficiency Syndrome). Early in the 20th-century the disease had established a foothold in rapidly growing cities in parts of Africa and spread via several vectors, including sexual transmission, blood transfusions and the reuse of needles during medical procedures. Long-distance labour migration to mines in central and southern Africa, where male miners had access to sex workers, likely hastened its spread. Internationally, two groups, haemophiliacs and homosexuals, were particularly vulnerable to early infection. Other sources of infection included blood transfusions, intravenous drug use and unprotected sex. The identification of the virus by the Pasteur Institute in 1983, launched a search for treatments. Research into antiretroviral drugs eventually led to the development of Highly Active Antiretroviral Therapy (HAART), which by the 1990s proved capable of halting the infection’s progression to AIDS. Drug patents, however, rendered these medications prohibitively expensive for the vast majority of those infected. International agreement in 1995 allowed countries facing medical crises to gain access to cheaper versions of the medications. Since the 1990s, education campaigns supporting safe sex, combined with the HAART regime, have helped reduce infection and death rates worldwide.
First recognized as a viral disease in the early 1980s, HIV spread to become a global pandemic that had infected nearly 30 million people by 2000.
The HIV virus originally infected primate populations in Central and West Africa. The zoonosis event (transmission of the disease to humans) probably occurred in the process of hunting or butchering primates for food. Over decades, human migration spread the virus across Africa and, during the 1960s, individuals, probably crew members of merchant vessels, carried the disease to different parts of the world. Other virally spread diseases – including SARS and monkeypox – are also likely to have originated by cross-species transmission.
LUC ANTOINE MONTAGNIER
1932–
French virologist who first identified the HIV virus
ROBERT CHARLES GALLO
1937–
American virologist who confirmed that HIV was responsible for AIDS
EARVIN ‘MAGIC’ JOHNSON, JR
1959–
American professional basketball player whose announcement of being HIV positive in 1991 helped ‘break the silence’ and overcome the stigma associated with HIV
Jonathan T. Reynolds
