1.What are
pathogens?
2. How do
pathogens
cause disease?
3. How did
Ignaz
Semmelweis
change the
way we look at
disease?
Pathogens and Disease
Starter :If you exercise regularly:
You have a higher _ _ _ _ _ _ _ _ _ _ _
ratio, therefore you have a higher
_ _ _ _ _ _ _ _ _ _ _ _ _.
You have a lower _ _ _ _ _ _ _ _ _ _
_ _ _ _ _ _ level which means you
have less chance of getting _ _ _ _ _
_ _ _ _ _ _.
1.What are
pathogens?
Pathogens and Disease
Infectious Diseases
2. How do
pathogens
cause disease?
3. How did
Ignaz
Semmelweis
change the
way we look at
disease?
Some infectious diseases are mild.
e.g.
Common cold
Tonsillitis
1.What are
pathogens?
2. How do
pathogens
cause disease?
3. How did
Ignaz
Semmelweis
change the
way we look at
disease?
Pathogens and Disease
1.What are
pathogens?
Pathogens and Disease
Infectious Diseases
2. How do
pathogens
cause disease?
3. How did
Ignaz
Semmelweis
change the
way we look at
disease?
Some infectious diseases kill.
e.g.
Influenza (Flu)
HIV (AIDS)
1.What are
pathogens?
2. How do
pathogens
cause disease?
3. How did
Ignaz
Semmelweis
change the
way we look at
disease?
Pathogens and Disease
Microorganism
Infectious diseases are caused by
microorganisms
entering the body.
Microorganisms
that cause diseases
are called
pathogens.
1.What are
pathogens?
2. How do
pathogens
cause disease?
3. How did
Ignaz
Semmelweis
change the
way we look at
disease?
Pathogens and Disease
Infectious
A person is said to be infectious if
they can pass
the
microorganisms
to another
person.
1.What are
pathogens?
2. How do
pathogens
cause disease?
3. How did
Ignaz
Semmelweis
change the
way we look at
disease?
Pathogens and Disease
Types of Pathogen
There are two groups of
microorganisms that are pathogens.
Bacteria
Viruses
1.What are
pathogens?
Pathogens and Disease
Differences Between Bacteria and
Viruses
2. How do
pathogens
cause disease?
3. How did
Ignaz
Semmelweis
change the
way we look at
disease?
Bacteria are single celled living
organisms. Some are useful, like the
ones used to make cheese, treat
seweage or make medicine.
1.What are
pathogens?
Pathogens and Disease
Differences Between Bacteria and
Viruses
2. How do
pathogens
cause disease?
3. How did
Ignaz
Semmelweis
change the
way we look at
disease?
Viruses are smaller than bacteria and
have regular shapes. Viruses cause
disease in all living organisms, even in
bacteria.
1.What are
pathogens?
Pathogens and Disease
The Cause of Disease
2. How do
pathogens
cause disease?
3. How did
Ignaz
Semmelweis
change the
way we look at
disease?
When bacteria
enter the body they
reproduce rapidly by
dividing into two.
They often produce
toxins. Some directly
damage cells.
1.What are
pathogens?
Pathogens and Disease
The Cause of Disease
When viruses enter the body they
2. How do
pathogens
cause disease?
3. How did
Ignaz
Semmelweis
change the
way we look at
disease?
enter the cells. They reproduce, destroying
the cell before they move onto another.
1.What are
pathogens?
2. How do
pathogens
cause disease?
3. How did
Ignaz
Semmelweis
change the
way we look at
disease?
Pathogens and Disease
Task 1:
Answer the questions in full
sentences.
1. What is a pathogen?
2. What is an infectious person?
3. Make a table to explain the
differences between bacteria and
viruses.
1.What are
pathogens?
2. How do
pathogens
cause disease?
3. How did
Ignaz
Semmelweis
change the
way we look at
disease?
Pathogens and Disease
Ignaz Semmelweis
In the 1850’s
many women
mysteriously died
after giving birth.
1.What are
pathogens?
Pathogens and Disease
Ignaz Semmelweis
2. How do
pathogens
cause disease?
3. How did
Ignaz
Semmelweis
change the
way we look at
disease?
The disease was
called childbed
fever. Many people
believed that those
that died were being
punished for having
a baby outside of
marriage.
1.What are
pathogens?
2. How do
pathogens
cause disease?
3. How did
Ignaz
Semmelweis
change the
way we look at
disease?
Pathogens and Disease
Ignaz Semmelweis
He noticed that his
medical students
went straight from
a dissection to
delivering a baby,
without washing
their hands.
1.What are
pathogens?
2. How do
pathogens
cause disease?
3. How did
Ignaz
Semmelweis
change the
way we look at
disease?
Pathogens and Disease
Ignaz Semmelweis
He insisted that all doctors at his
hospital should wash their hands before
delivering a
baby. Much
fewer women
died from
childbed fever.
1.What are
pathogens?
Pathogens and Disease
Ignaz Semmelweis
2. How do
pathogens
cause disease?
3. How did
Ignaz
Semmelweis
change the
way we look at
disease?
Semmelweis made it his
mission to educate other
doctors about his findings.
But he had trouble
convincing doctors that
there was an invisible
infectious agent that
doctors were carrying on
their hands.
1.What are
pathogens?
Pathogens and Disease
Ignaz Semmelweis
His battle still continues today.
2. How do
pathogens
cause disease?
3. How did
Ignaz
Semmelweis
change the
way we look at
disease?
1.What are
pathogens?
2. How do
pathogens
cause disease?
3. How did
Ignaz
Semmelweis
change the
way we look at
disease?
Pathogens and Disease
Task 2
You are Dr. Ignaz Semmelweis in 1857.
Write a letter to Dr. R Bledstrom, head
of medicine in Austria. Explain your
theory about childbed fever and your
struggle to convince doctors to take
appropriate action.
1.What are
pathogens?
Pathogens and Disease
Peer Marking Points
2. How do
pathogens
cause disease?
3. How did
Ignaz
Semmelweis
change the
way we look at
disease?
Childbed fever is caused by doctors carrying
an infectious agent on their hands.
If doctors wash their hands prior to delivery,
less women die.
Other doctors are unwilling to believe that
something they cannot see could cause
disease.
Other doctors are also unwilling to
acknowledge that they might be
responsible.