Download Infectious Disease

Infectious Disease
A disease caused by a Pathogen
that can be passed from person
to person
Pathogen
An organism that causes
disease
Most are microscopic
Louis Pasteur
Proved the Theory of Spontaneous
Generation was false
Showed that airborne microbes
were the cause of disease
Discovered microbes could be killed
by the heating of the liquid they
were in
Robert Koch
 Experimented with various dyes that
stain bacteria and make them more
visible under the microscope
 Also devised an ingenious method of
separating a mixture of bacteria
 Demonstrated that each infectious
disease is caused by a specific pathogen
Four Types of Pathogens
 Protists
Single celled organisms
Amoeba, Giardia, Plasmodium vivax
Dysentery, Giardia, Malaria
 Fungi
Dermatophytes
Athletes Foot, Ringworm
Viruses
Nucleic acid with a protein cover
DNA or RNA
Damage or destroy cells by
reproducing inside the cell
Adenovirus, Influenza virus, HIV
Cold, Flu, AIDS
Bacteria
Can damage cells directly
Streptococcus, Strep throat
Can damage cells indirectly by
producing toxins
Clostridium tetani,Tetanus
Can use shapes and arrangement of
bacteria to help identify
Bacteria
3 Shapes
Round
Rod
Spiral
Arrangements
Singles, pairs, clumps, chains
Bacterial Shapes
Dichotomous Key
Uses pictures to identify organism
Paired statements describe the
physical characteristics
Lead to other statements that will
Through the process of elimination
Lead to the organisms name
Sources of Pathogens
Soil, food, water, air
Contaminated objects
Infected animals
An infected person
Disease can be spread through
contact with any of the above
Sources of Pathogens.
How Pathogens are Spread
Contact with
Infected people
Infected animals
Contaminated animals
Contaminated food, water or soil
Predicting Casualties
Chart the growth of bacterium that
reproduces by simple cell division
once every 20 minutes.
Make a table and graph showing the
number of organisms created during
a 3-hour period.
Predicting Casualties
20 min Time Periods
Number of Cells
0
1
1
2
2
4
3
8
4
16
5
32
6
64
7
128
8
256
9
512
Exponential Growth
600
500
400
20 minute Time Periods
300
Number of Cells
200
100
0
1
2
3
4
5
6
7
8
9
10
Predicting Casualties
8
256.0
9
10
11
12
13
14
15
16
17
18
19
20
512.0
1,024.0
2,048.0
4,096.0
8,192.0
16,384.0
32,768.0
65,536.0
131,072.0
262,144.0
524,288.0
1,048,576.0
21
22
23
24
25
26
27
28
29
30
2,097,152.0
4,194,304.0
8,388,608.0
16,777,216.0
33,554,432.0
67,108,864.0
134,217,728.0
268,435,456.0
536,870,912.0
1,073,741,824.0
Cell Division
1.2E+09
1E+09
Number of Cells
800000000
20 minute Time Periods
600000000
Number of Cells
400000000
200000000
0
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31
Months
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
No Action
10,000.0
11,200.0
12,544.0
14,049.3
15,735.2
17,623.4
19,738.2
22,106.8
24,759.6
27,730.8
31,058.5
34,785.5
38,959.8
43,634.9
48,871.1
54,735.7
61,303.9
68,660.4
76,899.7
86,127.6
96,462.9
108,038.5
121,003.1
135,523.5
Educ. Campaign
10,000.0
10,200.0
10,424.0
10,674.9
10,955.9
11,270.6
11,623.0
12,017.8
12,459.9
12,955.1
13,509.7
14,130.9
14,826.6
15,605.8
16,478.5
17,455.9
18,550.7
19,776.7
21,149.9
22,687.9
24,410.5
26,339.7
28,500.5
30,920.6
Preventative Meds.
10,000.0
10,800.0
11,664.0
12,597.1
13,604.9
14,693.3
15,868.7
17,138.2
18,509.3
19,990.0
21,589.2
23,316.4
25,181.7
27,196.2
29,371.9
31,721.7
34,259.4
37,000.2
39,960.2
43,157.0
46,609.6
50,338.3
54,365.4
58,714.6
Predicting Casualties
160000
140000
120000
Cell Growth
100000
Months
No Action
80000
Educ. Campaign
Preventative Meds.
60000
40000
20000
0
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
Predicting Casualties
Months
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
Preventative Meds and Educ. Campaign
10000
9800.0
9584.0
9350.7
9098.8
8826.7
8532.8
8215.4
7872.7
7502.5
7102.7
6670.9
6204.6
5700.9
5157.0
4569.6
3935.1
3250.0
2510.0
1710.7
847.6
-84.6
-1091.4
-2178.7
Preventative Meds and Educational Campaign
12000
10000
8000
Cell Growth
6000
Months
4000
Preventative Meds and Educ. Campaign
2000
0
1
-2000
-4000
2
3
4
5
6
7
8
9
10 11 12 13 14 15 16 17 18 19 20 21 22 23 24
An Ounce of Cure
Set up Petri dishes with pathogens
Choose 3 medications to test for
growth inhibition
Be sure to label carefully and draw
accurately
Fighting Disease
3 Lines of Defense
First line of defense
Surfaces of
skin,
breathing passages,
mouth, stomach
Trap and kill most of the pathogens
that come into contact with them
How it Works
Skin
Destructive chemicals
Oil
Sweat
Dead cells fall off
Tightly packed cells don’t allow
access
How it Works
Breathing Passages
Mucus and cilia trap and remove
pathogens
Sneeze or cough to force
pathogens out
How it Works
Mouth and Stomach
Destructive chemicals
Saliva
Stomach acid
Second line of defense
Inflammatory Response
Fluid and white blood cells leak
from blood vessels into nearby
tissues
WBC’s help fight pathogens
Phagocytes
Inflammatory Response
Blood vessels widen and increase
blood flow to the area causing
redness
Leaked fluid causes swelling
Some pathogens do not grow and
reproduce at higher temperatures
Third line of defense
Immune System
T cells (Helper and Killer)
B cells
Antibodies
Lymphocytes distinguish between
different kinds of pathogens
Third line of defense
Antigens
Molecules that the immune system
recognizes either as part of the
body or as coming from outside
Like a team uniform
Third line of defense
AIDS
A virus that attacks the Immune
System
Enters Helper T cells
Over time, HIV does damage the
immune system, and the body will
lose it’s ability to fight disease.
Two types of Immunity
 Active
Results from getting disease or
From vaccination
Long lasting
 Passive
Antibodies given to fight disease
Short term (months)
 Both protect the body from pathogens
Active Immunity
When a person acquires immunity
because their own immune system
has produced antibodies in response
to the presence of a pathogen
Produced by cells of the immune
system as part of the immune
response
Active Immunity
Memory cells
When a pathogen enters the body
memory cells recognize the
antigen and start the immune
response so quickly that the
persons won’t get sick
Active Immunity
Vaccination
Vaccine
Pathogens (viruses) that have been
weakened or killed but can still
trigger an immune response
Antibiotic – Bacteria only
Active Immunity
3 things you can do to help your
Body recover when you are sick
Get plenty of rest
Drink lots of fluids
Eat well balanced meals
Passive Immunity
Does not last a lifetime (short term)
Antibodies that are passed to the
blood of baby from the mother’s
blood during pregnancy
An Ounce of Cure
Prepare an illustrated report of your
findings
Describe the effectiveness of each
medication and be sure to include
information about all medications
tested by the class
An Ounce of Cure
Conclusion paragraph
Discuss your recommendation for
the medicine to use against this
disease (which one and why)