Transcript Pathogens and Disease

Pathogens and Disease
Pathogens
A. Pathogen=an organism that causes
diseases
B. There are several methods used to
transport pathogens
Methods for Pathogen Transport
Pathogen type
A. Airborne
B.
Water borne
C. Foodborne
D. Vector borne
Transfer method
Breathing (pass through lung
epithelium)
Drinking (pass through intestinal
epithelium)
Eating (pass through intestinal
epithelium)
Bite/sting (directly to blood stream)
E.
Sexually transmitted Intercourse/close contact (pass
through skin)
F.
Direct contact
Skin/saliva (pass through skin or
into digestive tract)
Examples of pathogen types
A. Airborne pathogens
-can cause tuberculosis (a lung infection)
-symptoms: persistent cough,
productive cough, coughing up
blood, chest pain
B. Water borne pathogens
-can cause cholera
-found in water contaminated with human
feces
-main symptom: diarrhea/death by
dehydration
C. Food borne pathogens
-Salmonella comes from eating raw eggs,
chicken, pork, etc.
Symptoms: sudden onset of nausea,
abdominal cramping, and bloody diarrhea
D. Vector-borne pathogens
-Rabies
-Symptoms- paralysis, cerebral dysfunction, anxiety,
insomnia, confusion, agitation, abnormal behavior,
paranoia, hallucinations, progressing to delirium.
E. Sexually transmitted diseases:
-herpes (genital)
-syphillis
-gonorrhea
-human papillomavirus
-chlamidya
-bacterial vaginosis
-HIV
-and many more
F. Direct contact
-ringworm
Other examples of diseases
caused by pathogens
A. Viruses: chicken pox, polio, HIV,
influenza
B. Bacteria: tetanus, tuberculosis
C. Fungi: Athlete’s foot, ringworm
D. Protozoa: Malaria, sleeping sickness
E. Flatworms: Schistosomiasis=an infection
caused by worms laying eggs inside a
person
F. Roundworm: Elephantitis=caused by
worms blocking the lymphatic system
Homework/Classwork
1. Distinguish between HIV and AIDS. [2]
2. Discuss the cause, transmission, effects and
social implication of HIV and AIDS. [9]
3. Explain why antibiotics are effective against
bacteria, but not viruses. [4]
4. Due Friday
Antibiotics
A. Antibiotics block protein synthesis in
bacteria
B. Bacteria and animal cells synthesize
protein the same way, but the proteins
produced are not the same
C. Antibiotics use the differences to bind to
or inhibit production or functions of new
proteins
D. This prevents the bacteria from
reproducing
Antibiotics (continued)
E. Antibiotics do not treat viral illnesses
-viruses are made of genetic material only
-they do not synthesize their own proteins
-viruses require a host to be alive
Antibiotic resistance in bacteria
A. Genetic mutations
-can be caused by chemical or radiation
exposure or randomly
-bacteria that are not susceptible to the
antibiotic continue to thrive and multiply
B. Example
1. You are prescribed antibiotics
2. You take them for two days and feel okay
3. You stop taking the prescription
4. Two days later you feel ill again
What happened?
1. You didn’t take the antibiotics long enough
to kill all of the bacteria
2. All partly resistant bacteria had the chance
to reproduce and possibly become more
resistant