Transcript Unit 8: Communicable/Infectious Diseases

Communicable/Infectious
Disease
Infectious or Communicable

Disease caused by pathogens that can
be spread from one living thing to
another
Key Words




Susceptible – at high risk for a disease
Acute – an illness that develops having a
short duration
Chronic – an illness that develops and
lasts over a long period of time
Contagious – having the ability to be
transmitted
Key Words cont’d


Relapsing – a recurrence of symptoms
of a disease after a period of
improvement
Pathogens – microbes which can cause
an infectious disease
• Types: bacteria, viruses, fungi, protozoa,
worms
Bacteria

Microscopic, single celled organisms that can
cause disease
Three Shapes:
Coccus – round
Bacillus – rod shaped
Spirillum – spiral or twisted
Ideal conditions – warm, dark, and moist
Can live and multiply easily outside the body
Examples: Tetanus, Tuberculosis, Lyme
Disease, Strep Throat, Syphilis, and
Gonorrhea
Viruses
Bits of genetic material that can only be
seen by an electron microscope and
take over body cells
Can only live outside the body for a short
time but must multiply inside the body
Examples: Rabies, Polio, Common Cold,
Hepatitis, Mumps, Mononucleosis, Small
Pox, Chicken Pox, Shingles, and Warts

Fungi

Simple organisms that cannot make their
own food
Examples: Ringworm, Athlete's Foot
Protozoan

Single-celled organisms that are larger
and have more complex cellular
structure than bacteria; most are
harmless
Examples: Malaria, African Sleeping
Sickness
Worms

Flatworm and roundworm, while not
microorganisms are regarded as
pathogens and cause disease in the
human body
• Flatworms – flukes and tapeworms which
•
infect the intestines
Roundworms – trichinosis
• Infects intestines, muscles, and fluids under the
skin
• Pinworms – infects rectum
Methods of Transmission



Direct Contact
Indirect Contact
Animals/ Insects
Defense Against Infection

First line of defense – Structural
1. Skin
2. Mucous membranes in the mouth, nose and
3.
4.
5.
bronchial tubes
Cilia
Digestive juices of stomach (acid)
Tears
Second Line – Cellular Defense
White blood cells
•
Phagocytes – types of white blood cells that eat
up invaders
Lymph nodes – gland like structures that
serve as filters to screen out bacteria
Immunity – last line of defense
T-Cells – Lymphocytes that recognize
invaders and activate the “B” cells.
B-Cells – responsible for producing
antibodies that destroy invading germs.
Each antibody only good against a specific
pathogen

Inborn Immunity – temporary immunity that an
infant acquired from antibodies of the mother.

Acquired Immunity – the immunity the body
develops

Vaccines – disease prevention drugs that cause
the body to develop antibodies to fight diseasecausing germs, thus making the body immune to a
disease
Human Immunodeficiency Virus
(HIV)

A transmissible virus that attacks T-cells
of the immune system and causes
immune deficiency.
Acquired Immune Deficiency
Syndrome (AIDS)

Under 200 T-cells per micro liter of blood

A fatal, viral disease of the immune
system that creates a severe immune
deficiency and that leaves people
defenseless against infections and
cancer
Ways of Transmission



Contact with infected blood*****,
semen****, or vaginal secretions***
Injection of infected blood or blood
products.
Vertical transmission (from infected
mother to baby)/breast milk**
High Risk Behaviors



Anal intercourse
Injecting needles with multiple users
Vaginal intercourse
Other Risky Behaviors


Oral sex or other foreplay
Receiving blood (not probable today)
Early Signs of HIV






Tiredness and Fatigue
Skin rashes
Night sweats
Loss of weight
Constant Diarrhea
Sore Throat and Fever
Prevention of HIV and Other
STIs
1.
2.
3.
Abstinence – Do not have sex
Mutual Monogamous relationship – one
partner (and using condom)
Latex Condoms with lubrication
Testing for HIV

Elis Test – tests for antibodies

Western Blot – test used to confirm Elisa
results
• If negative, retest in 6 months
• If positive another Elisa is done
Chlamydia p.499



Chlamydia trachomais bacterium
Painful urination/discharge/ no
symptoms
Complications include- PID/sterility (vas
deferens &fallopian tubes)
Syphilis p.500


Spirochete bacterium enters and causes
chancre- painless, open sore
Chancre, rash, death
Gonorrhea p.501



Bacterium Neisseria gonorrhoeae
Discharge/burning sensation/no
symptoms
Sterility/PID
Herpes p.502



Herpes simplex virus
Cold sores/fever blisters
Entire genital region – can spread with
condom
HPV p.502





Human Papilloma Virus
Genital warts/no symptoms
Flesh colored or white and resemble a
cauliflower
Entire genital region
Can cause cervical cancer
Viral Hepatitis p.503



Several viruses
No symptoms/flu like/jaundice
Liver failure/death
Pediculosis p.503



Pubic lice
Itching
Must use either OTC or prescription
medicine
Trichomoniasis p.503

Similar symptoms to
gonorrhea/chlamydia