The passing of the Public Health Act (sanitary 1846) led to the establishment of the role of medical officer of health in Liverpool, and William Henry Duncan was appointed in January 1847 to ensure that sanitary conditions were improved in order to stem the spread of disease. Along with his local sanitarily inspector, Duncan had been credited for improving mortality rates in Liverpool (Ashton, 1989).
Following the enactment of the Public Health Act of 1848, John Simon was appointed as the first medical officer of health for London. However, in 1855 London was divided into 46 districts; each appointed at least one medical officer of health. The Public Health Acts of 1872 and 1875 made it a statutory duty for districts to appoint medical officers of health (Ashton, 1989).
Responsibilities of medical officers of health included tackling communicable and infectious diseases, the environment, water supply, sewerage, removing nuisances and fever hospitals (Engineer, 2001).