Vaccine pioneers

Average global life expectancy has more than doubled in the last two centuries. This is due to a range of two factors including better nutrition, housing and working conditions, as well as improved understanding of the causes of disease and its prevention. The development of vaccines against common serious illnesses has saved many lives.

Edward Jenner (1749-1823) was an English doctor who developed a way to prevent smallpox, a highly contagious disease caused by a virus which produced fever and a rash. Three out of ten people who caught smallpox dies and survivors were left with terrible scars. 

Jenner was born in the English town of Berkeley. He left his hometown to study medicine, but then returned to Berkeley to work as a doctor. In 1796, a dairymaid came to see Jenner about a rash on her hand. Jenner immediately recognised that she was suffering from cowpox- a mild illness caused by virus related to smallpox. Jenner had heard that people who caught cowpox seemed to be immune to smallpox and he wanted to test if this was true, by infecting someone first with cowpox and then with smallpox. He chose Phipps, his gardener's 8-year-old son, for the experiment.

Jenner scratched the skin on Phipp's arm and rubbed in some live material from the dairymaid's cowpox rash. Phipps became mildly ill but Cloze (1): trialsmouthprofitedprotectionrecoveredparalysiseven thoughcontractingdeafnessleading JXUwMDJhJXUwMDE3JXUwMDA2JXUwMDBjJXUwMDE5JXUwMDEzJXUwMDE3JXUwMDE3JXUwMDAx quickly. Then Jenner introduced some live material from a smallpox sufferer's rash to Phipps' body in the same way. Phipps did not become ill with smallpox, even when Jenner repeated the procedure.

Jenner had established the basic idea of introducing material under the skin to produce Cloze (2): trialsmouthprofitedprotectionrecoveredparalysiseven thoughcontractingdeafnessleading JXUwMDI4JXUwMDAyJXUwMDFkJXUwMDFiJXUwMDExJXUwMDA2JXUwMDE3JXUwMDFkJXUwMDA2JXUwMDAx against a disease. The process was named vaccination to acknowledge his work with cowpox- vacca means cow in Latin. Throughout his life Jenner continued his work and improved the smallpox vaccine after his death, making it safer and more effective.

Despite eh availability of a vaccination, smallpox continued to be a terrible problem in many parts of the world. A campaign against smallpox was introduced by the World Health Organization (WHO) in 1959 but was not properly funded until 1967. Smallpox was not completely eradicated until 1980.

Polio is a viral disease which can cause muscle weakness leading to Cloze (3): trialsmouthprofitedprotectionrecoveredparalysiseven thoughcontractingdeafnessleading JXUwMDI4JXUwMDExJXUwMDEzJXUwMDEzJXUwMDBkJXUwMDE1JXUwMDBhJXUwMDFhJXUwMDFh and even death. Outbreaks of polio have occurred regularly in the United States and Europe since the 19th century. Sufferers include  US President Franklin D Roosevelt who used a wheelchair as a result of Cloze (4): trialsmouthprofitedprotectionrecoveredparalysiseven thoughcontractingdeafnessleading JXUwMDNiJXUwMDBjJXUwMDAxJXUwMDFhJXUwMDA2JXUwMDEzJXUwMDAyJXUwMDE3JXUwMDFkJXUwMDA3JXUwMDA5 polio when he was a young adult. Some victims were left unable to breathe independently and had to live in an iron plug. Polio was a major concern for many Americans throughout the first half of the 20th century. the breakthroughs in the fight against polio can be credited to two scientists: Jonas Salk and Albert Sabin.

Jonas Salk (1914-1995) was born in New York City. He trained  as a doctor but went into academic research at the University of Pittsburgh. In 1947 he began to study the polio virus and by 1951, he had developed a vaccine, made from viruses grown in a laboratory and then destroyed. Testing for the vaccine began in 1952; Salk used his wife and three children as part of the early Cloze (5): trialsmouthprofitedprotectionrecoveredparalysiseven thoughcontractingdeafnessleading JXUwMDJjJXUwMDA2JXUwMDFiJXUwMDA4JXUwMDBkJXUwMDFm . By 1955, his vaccine was in general use and the number of polio cases in the US had fallen dramatically. Many Americans, panicked about the possibility of contracting polio at swimming pools and other public places, regarded him as a hero. Albert Sabin (1906-1993) was a Polish-born immigrant to the United States. After attending medical school, he worked as an academic-medical researcher at the University of Cincinnati College of Medicine. He demonstrated that polio was an infection of the digestive tract, transmitted by swallowing dirty water. Sabin believed that he could produce a more effective vaccine against polio by using weakened live viruses and by introducing these into the body through the Cloze (6): trialsmouthprofitedprotectionrecoveredparalysiseven thoughcontractingdeafnessleading JXUwMDM1JXUwMDAyJXUwMDFhJXUwMDAxJXUwMDFj , rather than through the skin.

The oral vaccine was successfully tested worldwide, in a co-operative programme involving Mexico, the Netherlands and the Soviet Union. in 1960, the United States approved Sabin's vaccine. It is now the main protection against polio throughout the world-cheap, easy to use and effective.

Sabin continued to research viruses and their connection with cancer. Salk studied AIDS and HIV and also wrote about philosophy. Neither man Cloze (7): trialsmouthprofitedprotectionrecoveredparalysiseven thoughcontractingdeafnessleading JXUwMDI4JXUwMDAyJXUwMDFkJXUwMDA5JXUwMDBmJXUwMDFkJXUwMDExJXUwMDAx financially from their discoveries.

A new influenza virus appears and the race is on to develop a vaccine. This sounds familiar, but the year is 1957, not 2020. Maurice Hilleman (1919-2005) , a microbiologist working for the US army, identified the virus and partnered with the pharmaceutical industry to direct the development of a vaccine, saving many lives. The vaccine was produced in just a few months, although, due to stronger safety regulations, this would not be possible today.

In 1963, Hilleman was working for the pharmaceutical company Meck. One night, his four-year-old daughter woke up with symptoms  of mumps. Although mumps was a common childhood illness, it could lead to severe complications, including Cloze (8): trialsmouthprofitedprotectionrecoveredparalysiseven thoughcontractingdeafnessleading JXUwMDNjJXUwMDAxJXUwMDA0JXUwMDA3JXUwMDA4JXUwMDBiJXUwMDE2JXUwMDAw . Hilleman collected a sample from his daughter and used a weakened form of this virus to develop a safe, effective vaccine. Some years later, his baby daughter received the vaccine which had been developed from the sample given by her older sister- a unique example of a sibling protecting, rather than infecting, a young child.

At Merck, research was well-funded and Hilleman was able to lead the development of more than 40 vaccines for both humans and animals. These included vaccines against measles and rubella, which, along with the mumps vaccine, are now routinely offered to children as the MMR. In 1998, an article was published which claimed that the MMR caused developmental disabilities in children, Cloze (9): trialsmouthprofitedprotectionrecoveredparalysiseven thoughcontractingdeafnessleading JXUwMDM0JXUwMDA5JXUwMDA0JXUwMDA1JXUwMDBkJXUwMDA3JXUwMDA5 to an anti-vaccination movement amongst many parents. The link was disproved and the World Health Organization estimates that between 2000 and 2015, over 12 million deaths were prevented by the measles vaccine alone.

Interestingly, Hilleman very nearly didn't become a micobiologist. AS a young man he had been happily working in sales - his older brother convinced him to attend university. It is claimed that he saved the lives of more people than any other 20th century scientist, Cloze (10): trialsmouthprofitedprotectionrecoveredparalysiseven thoughcontractingdeafnessleading JXUwMDNkJXUwMDEzJXUwMDEzJXUwMDBiJXUwMDRlJXUwMDU0JXUwMDFjJXUwMDA3JXUwMDFhJXUwMDEyJXUwMDBm he did not receive much public recognition.