MICROB W1 CH 1: History of Microbiology

What are the 4 sub-disciplines of Microbiology?

Bacteriology

Mycology (fungi)

Protozoology (protozoa)

Virology

Define Infection Control

prevention of microbial contamination, infection and spread from person to person

How can you eliminate/reduce the number of infectious diseases? (Why does infection control work?)

By understanding the morphology, environmental, chemical, physical conditions that contribute to microorganism's growth we can then apply proper infection control to effectively manage infectious diseases

Who recognized the existence of tiny disease causing particles that had the capabilities of spreading to humans via direct/indirect contact with contaminated objects? (hint: known for naming syphillis)

Girolamo Fracastoro

What contributions did Antoni van Leeuwenhoek make towards Microbiology? (4)

- discovered bacteria

- first person to see a microbe

- developed a primitive microscope **

- observed plaque on his own teeth

Who is credited for the concept of immunization? How did that credit come to be?

Edward Jenner - he injected cowpox (mild disease) into people and protected them from smallpox

Who is the father of immunology? What was his major discovery?

Louis Pasteur - discovered the use of heat to destroy vegetative bacteria and resistant bacterial spores

Which vaccines did Louis Pasteur create?

rabies, anthrax, cholera

What is pasteurization?

destroying pathogens by heating to 63C for 30 mins or 72C for 15 seconds

Which scientist discovered that bacteria existed in 2 forms? What are they?

John Tyndall

- heat sensitive and heat stable bacteria

What is tyndallization?

Steaming or boiling products at 100C for 20-45minutes for 3 successive days overnight with a resting period set to 37C.

- 37C will germinate any bacterial spores to be killed at the next heating.

Who discovered endospores?

Ferdinand Cohn

Who is Joseph Lister?

- discovered the role of airborne microorganisms

- discovered the use of antiseptics (phenols) to reduce microorganisms

- used antiseptic techniques to reduce surgical complications by boiling instruments, hand washing, and washing surgical materials in phenol

Who discovered gram staining?

Christian Gram

Gram stain consists of 2 dyes in solution: crystal violet and safranin (counter dye)

What does gram staining do? Why is it important?

Gram staining determines the difference in bacteria cell wall.

-> Gram positive will stain purple/blue.

-> Gram negative will stain red

Importance: Bacteria cell wall affects how they respond to antibiotics and therefore determine the severity of infections they can cause

Why is gram negative bacteria harder to kill?

Gram neg bact. has a harder outer cell wall that can release endotoxins.

-Large amount of endotoxins can cause inflammation, sepsis, or endotoxic shock.

Who was responsible for recognizing the importance of handwashing?

Ignaz Philipp Semmelweis

Which scientist discovered penicillin?

Alexander Fleming - observed mold had developed accidentally on a bacterial culture plate and the mold had created a bacteria-free circle around itself.

Who developed the electron microscope?

Wendell Stanley - virus magnified 35,000 times their normal size

Which scientist identified the specific causative agents for tuberculosis, cholera and anthrax?

Robert Koch

**Louis Pasteur also discovered cholera and anthrax

What are bacteriophages?

viruses that infect bacteria

What are prions?

Prions are proteins that can cause fatal brain diseases in humans and animals.

They are NOT microorganisms

When are microorganisms harmful?

- When they are someplace they should not be

- When they grow out of control