Charles Nicolle of France was awarded the 1928 Nobel Prize in Medicine for his discoveries about typhus.
But I believe his major contribution to infectious disease is what he called inapparent infection.
He defined them as cases where an individual is infected with a disease and spreads it without falling ill.
Today we call it the Asymptomatic transmission.
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Charles Nicolle’s father was a hospital doctor and very much wanted his son to be a clinical doctor.
At age 18, Nicolle began studying medicine at the university medical school in Paris.
In 1896 he experienced a hearing loss, which meant he could no longer use a stethoscope to assess patients’ health. In those days, that ended his clinical career.
Frustrated, he left France to take up a Microbiology post in a french colony in the distant Tunisia.
It was here he would make his great discoveries about epidemic typhus that earned him the Nobel prize.
Typhus was rampant in Africa but Nicolle had never seen a case of Typhus in France. It would occur among the inmates of the prisons of Tunis. He was scheduled to visit such a prison to examine a patient. Unfortunately, he became severely sick that day coughing blood.
Two of his colleagues went in his place. Nicolle recovered from his severe cough. The two who visited the prison were less fortunate – both died of typhus.
Then he dropped the idea of visiting prisons. Instead he targeted the native hosptal treating such unusual cases. As a custom, native patients were always stripped of their clothes and washed with soap and water before they were admitted to a ward.
Nicolle found out that in the hospital, the reception staff and laundry staff are getting infected, but not the ward attendants.
He concluded that something in the dress of the patient is carrying the infection.
Ultimately he traced the agent to be the ubiquitous body louse.
This discovery that Epidemic Typhus spreads by lice won the 1928 Nobel prize for Charles Nicolle.
Dr Ramakanta's Ideas 