ABSTRACT
This chapter shows that uncertainties over how 'catching diseases' spread have been constant themes in the history of medicine and disease throughout the modern era. It charts changing medical and public health understandings of, and practices for, the prevention, control and treatment of communicable diseases. The chapter starts with the first major contagions of the early-modern era: the 'Great Pox' and smallpox. It then explores in turn competing views and policies relating to the control of yellow fever and cholera, the development and spread of germ theories of disease in the nineteenth century, focusing on syphilis, sepsis and pulmonary tuberculosis, and the delineation of viral diseases such as polio, influenza and HIV-AIDS in the twentieth century. The chapter closes with brief reflections on emerging and re-emerging communicable diseases. Contagion was often represented by images of disease germs, mostly bacteria, but also vectors such as flies, dust, spitting, and poor hygiene.
