Communicable/ Infectious
Diseases
Unit 8
P. 484
Terms
SusceptibleRelapsingMonogamousPromiscuityAbstinenceRemissionOutbreak-
What is the Immune System Composed
of?
1.
2.
3.
4.
What 4 things on our skin kill pathogens?
1.
2.
3.
4.
Pathogens that are swallowed are killed
by_________.
Immune System P.485
LymphocytesTwo Types:
T CellsB CellsHow many lymphocytes do we have per
cubic millimeter of blood?
Immune System
Lymphocytes: White blood cells that help the
body fight pathogens (germs)
Two Types:
B Cells: produce antibodies (special
protein)
T Cells: Signal B cells to produce
antibodies
Immunity P.485
- The body’s resistance to disease-causing
agents.
ActivePassiveVaccine-
Immunity P. 485
The body’s resistance to disease-causing
agents.
Active: Resistance to disease due to the
presence of antibodies
Passive: Introducing antibodies into a
person’s blood stream
Vaccine: Weakened disease that is
introduced into the body to give immunity
(make antibodies)
Communicable/ Infectious Diseases P.
487
An illness caused by pathogens that can
be spread from one living thing to another.
Pathogens: Any germ that causes disease.
Contagious: Having the ability to be transmitted.
Epidemiology: The study of the source & the
spread of diseases.
5 Types of Pathogens P. 487
BacteriaFungiVirusesProtozoaHelminth-
What to know about types of pathogens
P.487
 Bacteria: Microscopic, single celled org., that cause
disease. Releases toxins, likes warm, moist dark
places.
 Fungi (yeast & mold): Simple org., can’t make own
food (ex: Athlete’s foot, ringworm)
 Viruses- smallest known pathogen, takes over our
healthy cells.
 Protozoa: Single celled org., can produce toxins that
cause disease.
 Helminith (worms): Not micro org., cause disease in
human body by infecting intestines, muscles, rectum
(ex: round worms or Trichinosins)
 Microbes: tiny organisms that can’t be seen by the
naked eye
Viruses
Viruses are not cells! Viruses cause disease
by invading cells forcing them to
reproduce viruses. Some remain in the
body for life. Can live outside the body for
a short time but must multiply inside.
*Smallest disease causing pathogen
Examples: rabies, polio, common cold,
hepatitis, mumps, chicken pox, shingles,
and warts.
6 Ways pathogens are spread P.488
1.
2.
3.
4.
5.
6.
How Pathogens are Spread P.488
1.May be spread from person to person through direct
contact (shaking hands, intimate kissing, sexual
intercourse, receiving a transfusion of the person’s
blood, touching ulcers or sores, of handling bodily fluids
like blood or urine)
2.May be spread in the air (coughing or sneezing)
3.Contact with contaminated objects (needles, razors)
4.Handling or being bitten by an infected insect/animal
5.Contaminated food or water
6.Not washing hands after using the bathroom
Possible Causative Factors
1.
2.
3.
4.
Host: person who is ill & is carrying the virus.
Environment: where the host lives.
Time: season of the year.
Agent: germ which caused the illness.
Susceptible: having a high chance of getting
disease.
Relapse: recurrence of symptoms of disease after
a period of improvement.
Defense Against Infection P.485
First line of defense: Structural
1. Skin (unbroken)
2. Mucous Membranes in the mouth, nose,
and bronchial tubes
3. Cilia
4. Digestive juices (stomach acids)
5. Tears
Second line of defense – Cellular
1. White Blood Cells
Phagocytes eat up invaders
T-Cells: lymphocytes recognize invaders and active
B-Cells
B-Cells: responsible for producing antibodies that
destroy invading germs
2. Lymph Nodes- gland like structures that serve as filters
to screen out bacteria
Last line of defense- Immunity (active, passive)
Inborn Immunity: temporary immunity that an infant has
(acquired from mother’s antibodies)
Bacterial STD’s
Chlamydia: painful urination and unusual
discharge from penis or vagina
PID: Pelvic Inflammatory disease (Infection of the
internal female reproductive sys.)
Syphilis: chancre appears, if it goes away doesn’t
mean STD is gone, its dormant.
Spirochete: bacteria that causes syphilis
Gonorrhea: infects linings of the male and female
genital and urinary tracts
Gonococcus- bacteria that causes gonorrhea
*Bacterial STD’s are curable with antibiotics
Viral STD’s P.502
Herpes I: blisters or sores appear on or around the
mouth, only transmissible when sores are
present
Herpes II: causes blisters to appear in genital
region
HPV: wart in genital area
(can cause cervical cancer in females)
Hepatitis (A,B,C,D,E): viral infection of the liver
*Drugs that help produce antibodies: Vaccines*
Parasites:
Pubic Lice
Trichomoniasis
HIV P.504
Transmissible virus that attacks T-cells of the
immune system and causes immune deficiency.
-The virus that causes AIDS. Some people who
become infected with HIV become ill and die
within six months. Others may remain in good
health and show no signs for six to ten years.
Opportunistic Infections: Infections like pneumonia
or cancer, that actually kill the person because
immune system is low due to HIV
Ways HIV is Transmitted p. 506
List the 7 Ways HIV is transmitted4 bodily fluids that can transmit2 bodily fluids that can not transmit but
does contain the virusWays HIV is Not transmitted-
Ways of Transmission (P.506)
-Contact with infected blood, semen, or vaginal
secretions.
-Injection of infected blood or blood products
-Infected mother to baby (Breast Milk)
High Risk Behaviors: Anal intercourse, injecting
needles with multiple users, vaginal intercourse.
Other Risky Behaviors: Oral sex, receiving blood
(not too probably anymore)
*Ways HIV is NOT transmitted (kissing, hugging,
coughing, bathroom facilities, insect bites,
sharing towels, prepared or served foods,
swimming, sports equipment)
How HIV Takes Over the Body P.505
The virus destroys the T-Cells & disables
their function of signaling the B-Cells to
produce antibodies. With the immune
system so low, the T cells are not able to
fight off other microorganisms & cancer
cells. The HIV cells multiply.
Early Signs of HIV p. 504
Tiredness
Skin rashes
Night Sweats
Loss of Weight
Diarrhea
Sore throat & fever
** Average time between HIV symptoms &
AIDS symptoms is 8-11 years.
p. 505
Kaposi’s SarcomaAIDS Dementia ComplexHIV Wasting Syndrome-
** Roughly 40,000 people in the US become
infected with HIV each year.
Incubation Period p. 512
Word given for the time period when you
turn from HIV- to HIV+
It may take 6 weeks to 6 months before
HIV antibodies will show up in the blood.
Most people develop antibodies in 6-12
weeks.
Treatment Drugs: slows down the germs
ability to reproduce. P.510
Cure: None
Tests P.512
ELISA: blood test that identifies whether a
person has HIV antibodies.
If negative- retest in 6 months, if positiveanother ELISA test is done to confirm.
Western Blot Test: this is also an antibody
test done to confirm the results of the
ELISA test.
Home Testing (2004)-
Treatments P.510
Anti-retroviral Drugs2 things the drugs do:
Cure-NONE
Acquired Immune Deficiency Syndrome
(AIDS)
The last and deadly stage of HIV.
When a person has 200 T-Cells or less
they are considered to have AIDS. After
symptoms marking the beginning of AIDS
development, most people die within two
years & the rest within five years.
Avoiding STD’s & HIV P.508
 Abstain from sex until marriage
 Change your behavior and be tested for STI’s
and HIV if you have become sexually active
 Have a monogamous relationship & marriage
 Choose a drug-free lifestyle
 Change your behavior if you use drugs
 Avoid sharing needles for tattoos or to pierce
body parts
 Follow universal precautions