Transcript L7 Pasteur and Koch

Our learning objectives today are:
1. To explain ideas about disease in the 18th C.
2. To investigate how Pasteur discovered germs
3. To explain why this discovery
was an important development
God
4 Humours
People had thought it
was a punishment
from God.
Why had
However the
these
church’s power was
theories
weakened and this
been so
idea was fading
Like spiritual
explanations, this
idea of humour
imbalances was
fading fast
popular?
Bad air (miasma)
People could see rotting food and waste in the
streets and knew they smelt terrible.
They assumed it must be the smell that caused
disease
People thought that
bad air caused
disease. This was
called a “miasma”.
Industrial towns were
more crowded and
dirtier than ever.
There were epidemics
of diseases like TB,
diphtheria and
cholera and this
theory seemed very
logical.
Bad air (miasma)
People could see
rotting food and waste
in the streets and
knew they smelt
terrible.
They assumed it must
be the smell that
caused disease
Spontaneous Generation!
The latest theory. The microscopes picked
up bacteria on decaying matter.
Scientists thought that the germs were
spontaneously (automatically) generated
(created) by the decay and then spread the
disease further.
The Daddy of
Bacteriology.
Pasteur was a
French scientist,
asked by a brewery
to investigate why
their alcohol was
going sour.
He thought it was
because of germs.
He proved that
germs in the air
were causing the
decay – not the
other way around …
He took two flasks – he
heated the liquid in
one flask to kill the
germs and make it
sterile.
He then drove the air
out so no more
bacteria could grow,
and sealed the flask.
100 years later, it was
still sterile (no germs)!
The other flask soured
with the bacteria.
He called this method
of heating and
sterilising liquids …
Many foods are pasteurised,
such as milk. This method also
paved the way for air-tight food
storage such as vacuum packing
and air-tight jars, tin cans etc.
He was asked to
investigate a disease in
silkworm.
He proved that
bacteria was spreading
the disease and
therefore linked germs
to disease (in animals)
He proved that germs caused
diseases in other animals too.
He accidentally injected a
chicken with some old chicken
cholera germs.
The chicken did not die!
He then injected the chicken
with fresh germs, and it still
didn’t die!
He had proved how Jenner’s
vaccination worked.
He now wanted to prove
germs caused human diseases
too …
Title – Louis Pasteur and Germ
Theory
Write down these key words
(underline) and a definition for
each:
 Miasma
 Spontaneous generation
 Germ Theory
Watch the Powerpoint on Pasteur and
answer the question below.
http://www.youtube.com/watch?v=WoewybcG-Y&feature=related
How did Pasteur work out his Germ theory?
Explain in your own words Clue: Milk and beer
How would Pasteur’s discovery
influence the world of medicine?
Robert Koch
• Built on the work of
Louis Pasteur
• IDENTIFIED bacteria
that caused specific
diseases.
• Scientific Method
• Paved the way for
vaccines and magic
bullets to be invented.
• TB (1882) – a major killer in 19th
Century caused the death of 1/7.
High mortality rate (if untreated
50%) Now vaccinations and
antibiotics. (Although 1/3 of the
world’s population have it)
Cholera (1883) – A
quick and lethal killer
which struck big cities
often.
Diseases Koch Identified
Anthrax (1877) – Now rare thanks to eradication programme. Spores still
survive however. Treatable with antibiotics. Developed as a biological
weapon by UK (ww2).
Legacy of Koch
• From his work Pasteur developed vaccines for
Cholera, Anthrax and Rabies
• His students went on to identify the bacteria
that causes: Diphtheria, pneumonia, Typhoid,
Gonorrhoea, Meningitis, Leprosy, Plague,
Tetanus, Syphilis.
• Won Nobel Prize (later, 2 other members of
his team would also).
Team Spirit
• Paul Ehrlich (German): Nobel Prize winner and
inventor of the first magic bullet.
• Gerhard Domagk (German): Nobel Prize
winner and inventor of the first
sulphonomide.
• Julius Richard Petri (German): Obvious!
Koch’s team of scientists would be perhaps
the most successful in the history of
medicine.
Make a CV for Koch
•
•
•
•
•
•
Name
Job
Location
Main influences
Discoveries
Achievements
GERM THEORY
Pasteur convinced
other scientists that
diseases are caused
by microbes
(bacteria or Germs)
Identifying Bacteria
Koch was the first
scientist to identify
specific microbes
that caused
individual diseases
EXPLAIN THE LINK:
1. Anti-biotic medicines
2. Vaccines
3. Cleaner hospitals
4. Public Health
5. Antiseptic surgery
6. Training of Doctors and Nurses
7. More investment in Science
8. Higher life expectancy
Koch or Pasteur?
A French scientist
PASTEUR
Koch or Pasteur?
Worked with Paul Ehrlich
KOCH
Koch or Pasteur?
Investigated a disease in silkworm
PASTEUR
Koch or Pasteur?
Discovered what caused TB
KOCH
Koch or Pasteur?
Discovered GERMS
PASTEUR
http://www.youtube.com/watch?v=rR4sC9RDa
KY&safe=active