Charles Nicolle

Charles Nicolle was a French bacteriologist, born in Rouen in 1866 and died in 1936, who received the Nobel Prize in Medicine for identifying lice as the transmitter of epidemic typhus. The son of a Rouen hospital doctor, he took his medical degree at the Pasteur Institute of Paris in 1893 and directed the bacteriological laboratory in Rouen until 1902. Growing deafness made patient contact harder and pushed him toward laboratory work. From 1903 until his death he directed the Pasteur Institute in Tunis, which he made an international centre for vaccine production and research, funding it partly through paid medical services so that it did not depend on public money. He noticed that typhus patients stopped infecting others after a hot bath and a change of clothes, concluded that lice carried the disease, and in 1909 confirmed this by passing typhus between chimpanzees through lice; he later used guinea pigs. He never produced a practical typhus vaccine, but he found sodium fluoride useful for sterilizing parasites while keeping their structure, and used it for vaccines against gonorrhea, some staphylococcal infections and cholera.