Microbiology, 2021

660 16 • Disease and Epidemiology
Joseph Lister provided early epidemiological evidence leading to good public health practices in clinics and
hospitals. These settings were notorious in the mid-1800s for fatal infections of surgical wounds at a time
when the germ theory of disease was not yet widely accepted (see Foundations of Modern Cell Theory). Most
physicians did not wash their hands between patient visits or clean and sterilize their surgical tools. Lister,
however, discovered the disinfecting properties of carbolic acid, also known as phenol (see Using Chemicals to
Control Microorganisms). He introduced several disinfection protocols that dramatically lowered post-surgical
infection rates. 7 He demanded that surgeons who worked for him use a 5% carbolic acid solution to clean their
surgical tools between patients, and even went so far as to spray the solution onto bandages and over the
surgical site during operations (Figure 16.8). He also took precautions not to introduce sources of infection
from his skin or clothing by removing his coat, rolling up his sleeves, and washing his hands in a dilute
solution of carbolic acid before and during the surgery.
Figure 16.7 (a) Florence Nightingale reported on the data she collected as a nurse in the Crimean War. (b) Nightingale’s diagram shows
the number of fatalities in soldiers by month of the conflict from various causes. The total number dead in a particular month is equal to the
area of the wedge for that month. The colored sections of the wedge represent different causes of death: wounds (pink), preventable
infectious diseases (gray), and all other causes (brown).
7 O.M. Lidwell. “Joseph Lister and Infection from the Air.” Epidemiology and Infection 99 (1987): 569–578.
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2249236/pdf/epidinfect00006-0004.pdf.
Access for free at openstax.org.