At the beginning of the 19th century, though there had been some advances in medical knowledge, scientists still did not understand what caused disease.
The next great breakthrough came in the 1860s when Louis Pasteur, using Lister’s microscope, discovered germs and revolutionised medical knowledge.
In the 1850s, French scientist Louis Pasteur was employed by a brewing company to find out why their beer was going sour. Through the microscope he discovered micro-organisms growing in the liquid. He believed that these germs, so-called because they appeared to be germinating or growing, were causing the problem. He discovered that the microscopic bacteria which turned beer bad could also be killed by heating, ie by pasteurisation.
In 1861, Pasteur published his germ theory and, by 1865, had proved the link between germs and disease. In 1879, he discovered a vaccine for chicken cholera. He found that when the germ was exposed to air it weakened, and that injecting this weakened germ into chickens prevented them from catching the disease. In 1881, he developed a vaccine for anthrax and by 1885, a vaccine for rabies.
In the late 1870s the German, Robert Koch began to apply Pasteur’s ideas to human diseases. In doing so, he created the science of bacteriology. He identified the bacteria which caused anthrax (1875), TB (1882) and cholera (1883). Koch was very thorough. To isolate the anthrax bacteria, he transferred the bacteria through 20 generations of mice until he was satisfied that he had the right micro-organism. Koch also developed a medium for growing bacteria and a way of staining them so that they could be seen more easily.
Koch’s success spurred Pasteur into action again. At the time, there was intense rivalry between France and Germany, following a war in 1870. The German government had given Koch a team of scientists to assist him and now the French government decided to back Pasteur, who went on to develop vaccines.
In the 1880s and 1890s rapid progress was made in identifying the bacteria that caused disease and in developing vaccines.
silver bullets, drugs designed to target specific germs.
The 19th century also saw progress in the area of orthopaedics. There were a number of pioneering Welsh bonesetters who helped bring about changes in the treatment of orthopaedic injuries.
In the mid-19th century Thomas Rocyn Jones set up a practice in the Gwent valleys and gained a reputation for treating fractures, dislocations and muscle injuries. He developed new types of splints to treat tendon injuries. He also added supports to the insides of shoes to relieve foot strain. However, it was another 50 years before his ideas came into widespread use in the treatment of orthopaedic injuries.
Several generations of the Thomas family of Anglesey also made important contributions. Evan Thomas moved to Liverpool, specialising in bone and joint diseases. His five sons all became doctors.
The eldest, Hugh Owen Thomas, a surgeon, is considered to be the father of modern orthopaedic surgery. He also designed splints.
The Thomas splint was designed in 1875 to help heal fractures of the femur (thigh bone). It helped ease pain and reduced the number of amputations needed. The Thomas splint was widely used for leg injuries in both world wars and is still in use today.
Sir Robert Jones was the nephew of Hugh Owen Thomas. He studied with his uncle and then became the first lecturer in orthopaedics at Liverpool University. During World War One, he was put in charge of military orthopaedics. By using the Thomas splint he reduced the death rate from fractures fell from 80 per cent to 20 per cent.
Between them, these Welsh bonesetters laid the foundations of modern orthopaedic surgery.