© 2001 by Jones and Bartlett Publishers

Early human interactions with microbes Early Plagues What did people THINK was causing disease?

The Miasma Theory People thought disease was spread by “miasmas”, or “bad quality of air”

Girolamo Fracastoro Named the disease syphilis in a poem Proposed disease could be transmitted by minute particles in three ways: Air Fomites (inanimate objects) Direct contact

1300s, 1600s Waves of Bubonic Plague Brueghel's 1562 work "The Triumph of Death." Pieter the Elder Brueghel/The Bridgeman Art Library/Getty Images

1666 The Bubonic Plague In the village Eyam, 259 out of 350 died from the plague 1/3 of the population of London died in one wave of the plague The origin of a familiar nursery rhyme: “Ring around the rosie”

Ring a ring of rosies A pocket full of posies Achoo! We all fall down. Referred to the rose shaped splotches A futile attempt to ward off “evil spirits” Indicated the fits of sneezing Death.

Village of Eyam

The Riley Graves

List List of Plague victims

A. The Beginnings of Microbiology

1665 Robert Hooke Published Micrographie, a collection of observations of microbes described early microscopes included drawings of microscopic living things coined the term “cells”

1674 Anton van Leeuwenhoek Made microscopes that could magnify objects over 200 times Viewed protozoans, fungi, algae and bacteria Called them “animalcules”

B. The Transition Period

1600’s Spontaneous Generation The belief that rats, maggots, toads, and other living things “arose” out of lifeless objects For example: maggots were spontaneously generated from rotten meat

1670’s Francisco Redi - disputed spontaneous generation

Other important discoveries: 1798 Edward Jenner - Discovered vaccine for smallpox Mid 1800’s Semmelweis - Proved that handwashing in chlorine water stopped the spread of blood poisoning from corpses to maternity patients by doctors Snow – Proved that chlorination of water stopped cholera outbreaks

Map of London showing Cholera outbreaks

C. The Golden Age of Microbiology 1857-Early 1900’s

Louis Pasteur - France Proved yeast had a role in wine fermentation Suggested microorganisms could be the cause of disease Pasteurization - heating to kill bacteria Disproved spontaneous generation by using a swan-necked flask Created vaccines for anthrax and rabies

Robert Koch - Germany Isolated the anthrax bacterium Transmitted them to healthy mice and induced the disease This led to Koch’s Postulates Discovered pure culture techniques on solid media (Agar) Agar – a seaweed derived powder used to solidify jams and jellies Fanny Hesse – introduced agar into the lab

1909 – Paul Ehrlich develops a drug to cure syphillis Used chemicals to kill bacteria (Chemotherapy) The arsenic compound was named Salvarsan Known as a “Magic Bullet” to cure syphillis

1928- Alexander Fleming Discovers Penicillin Mold grew in his Petri dish of bacteria A “zone of inhibition” surrounded the mold The mold extract was called penicillin