The ethical importance of infectious diseases

The ethical importance of infectious diseases partly relates to the fact that their consequences are almost unrivalled. Historically they have caused more morbidity and mortality than any other cause, including war (Price-Smith, 2001). The Black Death eliminated one-third of the European population in just a few years during the mid-fourteenth century (Ziegler, 1969); the 1918 flu epidemic killed between 20 and 100 million people (Crosby, 2003); tuberculosis (TB) killed a billion people during the past two centuries (Ryan, 1992); and smallpox killed between 300 and 500 million people during the twentieth century alone – i.e. three times more than were killed by all the wars of that period (Oldstone, 1998).

Second, because the public health measures used to control them sometimes involve infringement of widely accepted individual rights and liberties, infectious diseases raise difficult philosophical questions about how to strike a balance between the goal to protect the greater good of public health and the goal to protect individual rights and liberties. Quarantine and travel restrictions, for example, violate the right to freedom of movement. Other public health measures – such as contact tracing, the notification of third parties, and the reporting of the health status of individuals to authorities – can interfere with the right to privacy. Mandatory treatment and vaccination, finally, conflicts with the right to informed consent.