John Snow Biography (1813-1858)
John Snow was a British physician of the Victorian era who helped introduce the use of anesthesia in surgery; he also attempted to show, in 1854, that cholera was a water-borne disease. His careful mapping of the distribution of cholera cases in London is the first known example of epidemiological research.
Snow was born in York, England, on March 15, 1813, the oldest of nine children. His father was an unskilled laborer and the family lived in one of the poorest sections of York, an industrial shipping area along the River Ouse. Snowwas educated until the age of 14 at a common day school for the poor. In June of 1827 he arrived in Newcastle, 80 miles from his home, to begin a six year apprenticeship in medicine under William Hardcastle. Hardcastle taught himthe day-to-day business of running a medical practice and dispensing medicine. During his apprenticeship, Snow also attended lectures at the Newcastle Infirmary.
In 1833 Snow became an assistant to a physician named Watson, not far from Newcastle. A year later he returned to York, where he joined the practice of Joseph Warburton. In October of 1836 he moved to London to begin advanced studies at the Hunterian School of Medicine. He became a Member of the Royal College of Surgeons of England in May of 1838, and in October of that year he qualified as a Licentiate of the Society of Apothecaries. Shortly afterward he set up his own practice in the Soho district of London. Although Snow was now fully qualified to practice medicine, he continued in his spare time to gain additional medical qualifications. He obtained a Bachelor of Medicine degree from the recently formed University of London in November 1843, and a year later received a Doctorate of Medicine from the same institution. In June 1850 he became a Licentiate of the Royal College of Physicians of London.
The use of anesthesia was first demonstrated in England in December 1846 by adentist named James Robinson. Within days of its introduction, Snow had become sufficiently interested in its potential to investigate its scientific foundation. Soon he had designed his own inhaler for ether, and was using anesthesia in his hospital practice. In 1847 he published a small textbook on the proper administration and the effects of anesthetic vapors. He became widely acknowledged as the leading British expert on the subject and his medical practice was increasingly devoted to the use of anesthesia. His most famous patient was Queen Victoria, who called upon Snow to administer chloroform during the delivery of two of her nine children. His patients ranged widely in socialposition and wealth. Snow frequently practiced medicine in the poorest quarters of London.
In 1832, while still in his medical apprenticeship, Snow had treated choleravictims during an outbreak in the coal mining region near Newcastle. Cholera,which caused violent diarrhea and vomiting, was fatal to about half of its victims in the early 19th century. Between 1832 and 1854, a series of epidemics swept England and Snow had the occasion to witness its ravages many times.He observed that the disease tended to break out late in the summer, occurredmost often amongst the poor, and seemed to arise in localized areas, often isolated geographically from one another. The prevailing belief at the time was that cholera was caused by "miasmas" or bad vapors, and that those of low moral character were more vulnerable. Snow, on the other hand, suspected the disease might be spread by a waterborne microorganism. In the first week of September 1854, over six hundred people died of cholera in a small area of Soho. Snow began to investigate the source of water that supplied this area, andtraced the outbreak to a particular water pump on the now famous Broad Street. It had, for several weeks prior to the outbreak, been spewing forth a foamybrown water that smelled of raw sewage. Snow pleaded with the Board of Guardians of the local parish to remove the pump handle. By the time the handle was removed, the incidence of cholera had already begun to subside. Nonetheless, the publicity surrounding Snow's investigation drew attention to the general lack of sanitation efforts in London, and a complete overhaul of the city'swater and sewage systems was begun. Cholera never returned. The data Snow collected and the maps he constructed showing the distribution of the disease in relation to source of water became the first known epidemiological survey of an illness. Because of this careful study, Snow is often referred to as thefather of modern epidemiology.
Snow suffered from kidney disease and chronic poor health. He became incapacitated by a stroke shortly before he died, on June 16, 1858, at the age of 45.