 Infectious diseases are illnesses caused by
microorganisms
 Microorganisms are small things found everywhere
 Most do not cause disease and actually help your
body function normally
 Certain ones do CAUSE infectious Diseases that can
spread directly or indirectly
 These are known as contagious or communicable
diseases
 They are passed from person to person, object, or
animal
•Touching
•Coughing/Sneezing
•Sharing
•Sexual Contact
 Pathogens are tiny organisms that cause
communicable diseases
 Infection occur when pathogens enter the body,
multiply, and damage cells
 Bacteria-tiny one-celled organisms that live nearly
everywhere
o Common types: strep throat ( if not taken care of can
cause heart damage), boils, bacterial pneumonia,
impetigo, sinus infection, tuberculosis, hepatitis
 Virus- smallest disease causing organism, not alive,
cannot reproduce on their own
o Common types- measles, mumps, chicken pox, common
cold, influenza, mononucleosis
• The West Nile virus broke out in 2000 in the
northern part of the United States for several
months. The news reported the number of
deaths and informed the public about the
virus and how it is transmitted. What are pros
and cons to intense media coverage of a
disease outbreak?
• http://www.youtube.com/watch?v=KOWrjsENY
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Good hygiene
Hand washing
Take warm showers
Eat properly
Get enough sleep
Use clean utensils
Do not share drinking glasses with others
Wear suitable clothing outside and use insect repellant
Examine your body for ticks
Avoid contact with contagious people
Cover your mouth-sneezing or coughing
Stay away during contagious period- length of time when a
particular disease can spread from person to person
 Direct contact with the infected person
 Indirect contact with an infected person
 Contact with a vector- an organism such as an
insect, that transmits pathogens
 Other contacts- drink or eat after someone,
uncooked meat, receive blood contaminated
 Carriers- bacteria can remain dormant in the lungs
of some people because they do exhibit any
symptoms of the disease. Carriers get rid by taking
medicine and living a healthy lifestyle.
• Ear piercing. Is it safe?
• What are risks of ear piercing?
• What are ways that the risks could be
reduced?
 Drugs that can kill or slow the growth of
bacteria
 Can be made from bacteria and mold
 Penicillin was the first discovered in 1928 by
Alexander Fleming on accident
 1940 is when it became available to people
 It is important to take all of the medicine to
ensure to get rid of all the bacteria
• We live in a society of electronics. Compare
electronic viruses to viral viruses. How are
they similar and different?
• Skin- Outside layer of skin is tough and made up of
dead cells. This makes it difficult to get germs
through.
• Hairs- Traps germs around eyes and nose and keeps
them from getting in the body. Cilia keeps germs out
of the lungs.
• Tears-Wash out germs from your eyes.
• Mucus-Traps germs and contains chemicals to attack
and destroy the germs.
• Saliva and Stomach acid- Germs that enter the mouth
and stomach are killed by saliva and stomach acid.
 Immune system- main line of defense- cells,
tissues, and organs that fight off pathogens and
disease
 Immunity- body’s ability to resist germs that cause
particular disease
 Two major kinds of defense strategies:
o Nonspecific Response-Inflammation or increased blood
flow to affected area, send white blood cells to speed
to the affected area and destroy invading pathogens
o Specific Response- Set in motion if it survives nonspecific response, more specialized, it can recognize
this pathogen if it enters the body again.
 Lymphatic System- secondary circulatory system that
helps the body fight pathogens and maintain its fluid
balance
o Lymphocytes react to antigens that are released by
invading pathogens
o Our body produces antibodies –proteins to attach to
antigens and keep them from harming us
 Two types of Immunity
 Natural immunity- born with it
 Acquired immunity- develops over lifetime
 Passive acquired immunity- receiving antibodies from mother in womb
 Active acquired immunity- Body makes specific antibodies in response to
invasion by a specific pathogen
 Immune Response- B cells-production of antibodies and T
cells- destroy pathogens
 Vaccines-preparation of dead or weakened pathogens
that is injected into the body to cause the immune system
to produce antibodies
• Write down three ways that the body can
defend itself.
• “The Germs Go Marching In”
• Disease that can be passed from person to
person by any form of sexual contact.
• STD/Is can be caused by bacteria, viruses,
fungi, or parasites
• Some STD/Is can cause lasting pain and
infertility or the inability to produce children
• Some can cause brain damage, paralysis, and
death
• Handshake Activity
 Sexual abstinence is the refusal to take part
in sexual activity
 Can avoid contracting STI
 There are no vaccines for STIs
 Your body cannot build immunity to STIs
 Choose your friends carefully- they should
share your morals and values
 Avoid being alone with a date
 Know your limits and communicate them
with your date before you go out
 Say no through your words and actions
 Seek advice from a trusted adult on handling
difficult situations
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Chlamydia
Human Papillomavirus
Genital Herpes
Gonorrhea
Syphilis
Trichomoniasis
Genital warts
Nongonocceal urethritis
Pelvic Inflammatory Disease
 Urinary Tract Infections
 Vaginal Yeast Infections
 Deadly disease that affects the body’s natural
ability to fight infection
 Human immunodeficiency virus (HIV) is the
virus that causes AIDS
 The only way to tell if infected is through a
blood test
 There is no vaccine to prevent infection of
HIV and no cure for AIDS
 Carriers appear healthy but can pass HIV to
others
 Attacks immune system, activates B cells and
destroys T cells
 Symptoms
o Swollen lymph nodes, fatigue, diarrhea, weight
loss, fever
 Presence of opportunistic infection- infection
that rarely occurs in a healthy person
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Sexual Contact
Mother to Child
Drug Use
Blood Transfusion
• When visiting an AIDS patient, you have to
wear protective mask and clothing not to
protect yourself but the AIDS patient. Why?
 Not spread through the air
 Not spread through kissing- closed mouth.
Open mouth, only if both people have sore
 Not spread through casual contact- shaking
hands
 Not spread by mosquitoes that have bitten
an infected person
 Not spread by sharing eating utensils with an
infected person
 Not spread by donating blood
 Avoid sexual contact
 Avoid drug use
• How is HIV spread? Not spread? How would
you feel about having a student in class with
AIDS? How would the person like to be
treated by others?
• Explain how STD’s are spread and what you
think can be done to reduce the spread of
STDs. Ask students how education can slow
the spread of STDs?
• Two Columns- One for Method of Preventing
Spread of Disease and Two- Method of
Spreading Infectious Diseases
• You and some students are at a party at a
friend’s house when another student arrives
with a bottle of a new soft drink. He is telling
everyone how good it is, and then he offers
you a drink of it.” Ask the students if it is OK
to drink after him?