Infectious Diseases
Health II
Pre-Test
1. What is a pathogen?
2. List at least 3 types of pathogens.
3. List 3 ways pathogens are spread
4. How do you treat bacterial diseases?
5. What is a vaccine?
6. Name 2 common bacterial diseases
7. Name 2 common viral diseases
Answers
1. Any agent that causes disease
2. Bacteria, viruses, fungi, protists, parasites, rickettsia
3. Person to person, food and water, environment, animals
4. Antibiotics
5. Substance made of killed or weakened pathogens or from genetic
material introduced into the body to create immunity
6. Strep throat, meningitis, sinus infection, salmonellosis, tetanus
7. Flu, common cold, mumps, measles, mononucleosis, hepatitis,
Ebola
Pathogens
 ANY AGENT THAT CAUSES DISEASE
 Bacteria
 Tiny, single-celled organisms that live almost everywhere on Earth
 Most bacteria are harmless and help with bodily functions
 Bacteria in mouth, intestines
 Harmful bacteria make you sick when they grow on or in your body
 Example:
 Some give off poisons (tetanus/toxins) that damage cells
 Sinus infections
 Most harmful bacteria are killed by our immune system, others need
antibiotics to treat and cure infections
Pathogens
 Viruses
 Smaller than bacteria
 Disease-causing particles made up of genetic material
surrounded by a coat of protein
 the virus finds a living “host cell” and forces it to reproduce and
“attack” more cells
 Colds, flu, measles, AIDS
Pathogens
 Fungi (fungus)
 Organisms that absorb and use nutrients from other living or dead organisms
 Mushrooms
 Athlete’s foot, ringworm
 Protists
 Larger and more complex than bacteria
 Malaria
 Parasites
 Animals—get their energy and nutrients by feeding on other living organisms
 Lice, tape worms, etc.
 Rickettsia
 Pathogens that resemble bacteria
 Invade cells of other organisms
 Enter humans through bites from fleas, ticks, or lice
 typhus
How are they transmitted?
 Person to person
 Airborne (sneezing, coughing, touching anything drops landed on) kissing, drinking
from same glass, direct contact (tetanus)
Dirty Hands Suck
 Food and water
 Contaminated food (from humans, from infected animal)
 Examples?
 Water from streams or lakes, sewage,
 Typhoid, cholera, dysentery
 Environment
 Pathogens are all around you—few can cause disease
 Tetanus present in soil
 Animals
 Pathogens live on/in animals
 Ringworm from pets, mosquitos carry malaria, yellow fever, encephalitis, ticks carry
Lyme disease
How are they treated?
 Bacterial diseases
 Antibiotics-medicines used to kill or slow the growth of bacteria
 Penicillin
 CANNOT be used to treat colds or viral diseases
 Antibiotic resistance: bacteria are no longer killed by a particular
antibiotic
 Improper use=build up of antibiotic resistant bacteria
 Viral Diseases
 Not much is known, so most concentrate on relieving symptoms and
stopping production of viruses inside cells
 Fungal Infections
 Over-the-counter or prescription medicine
 Protistan, parasitic Infections
 Prevention—good hygiene, sanitation
Vaccines
Substances made of killed or weakened pathogens or
from genetic material introduced into the body to
create immunity
The body begins to make WBCs called memory cells
If the specific pathogen enters the body , the memory
cells and their antibodies fight the pathogen before it
can cause disease
May need boosters for vaccines
Flu?
Common Bacterial Infections
 Tetanus
 Symptoms- Severe muscle spasms
 Transmission- Tetanus causing bacteria found in soil
 Prevention- vaccine and boosters
 Treatment- antibiotics
 Strep Throat
 Symptoms- sore throat, fever, yellow or white specks on tonsils
 Transmission- contact with mucus from infected person
 Prevention- avoid contact
 Treatment- antibiotics
 Meningitis-inflammation of membranes covering brain and spinal
chord
 Symptoms- severe headache, fever, stiff neck, sensitivity to light, nausea
 Transmission- contact with saliva or mucus from infected person
 Prevention- vaccine, avoid contact
 Treatment- antibiotics—if caught early enough
Common Bacterial Infections
 Sinus Infection
 Symptoms- headache, tenderness of sinuses, thick greenish
mucus, pressure in head
 Transmission- contact with mucus
 Prevention- avoid contact and allergens
 Treatment- ??
 Salmonellosis- an infection of the digestive system
 Symptoms- headache, cramps, diarrhea, nausea, vomiting
 Transmission- eating contaminated food
 Prevention- thorough cooking, hand washing, refrigeration
 Treatment- OTC meds for symptoms, sometimes antibiotics
Common Viral Infections
 Flu
 Symptoms- headache, sore muscles and throat, fever, vomiting, ect.
 Transmission- contact with saliva or mucus
 Prevention- vaccine and avoid contact
 Treatment- rest, fluids
 Cold
 Symptoms- sore throat, sneezing, runny nose, mild cough
 Transmission- contact with saliva or mucus
 Prevention- wash hands, avoid contact
 Treatment- rest, fluids
 Mumps
 Symptoms- pain and swelling of glands in throat, fever, headache
 Transmission- contact with infected airborne droplets and infected person
 Prevention- vaccine
 Treatment- see doc. Rest, fluids
Common Viral Infections
 Measles
 Symptoms- fatigue, runny nose, cough, fever, small white dots in mouth, rash
on body
 Transmission- contact with saliva or mucus
 Prevention- vaccine
 Treatment- see doc. Rest, fluids
 Mononucleosis
 Symptoms- fever, swollen lymph nodes, sore throat, weakness
 Transmission- contact with saliva or mucus
 Prevention- avoid eating/drinking after infected person
 Treatment- see doc. Rest, fluids
 Hepatitis
 Symptoms- inflammation of liver, jaundice, fever, darkening of urine
 Transmission- contact with bodily fluids, contaminated food or water
 Prevention- vaccine for A and B, wash hands, avoid contact
 Treatment- see doc. Rest, meds, no cure for Hep. B and C
What is a disease outbreak?
 Occurs when a disease spreads in greater numbers
than expected in a community or region or during a
season
 1 community or extend to several countries
 Example?
 Even 1 case could be considered an outbreak
 Unknown disease, new to community, absent for a long
period of time
 Ex. Whooping cough
Epidemic vs Pandemic
 PAIR AND SHARE
 Talk to a partner and find out what you each know about
an epidemic and a pandemic.
 What are they?
 What is the difference?
 Examples of each?
Epidemic
 Occurs when an infectious disease spreads rapidly to
many people
 Ex. SARS (2003) killed nearly 800 people worldwide
Pandemic
 GLOBAL disease outbreak
 When an epidemic gets out of hand, it becomes a
pandemic
 HIV/AIDS—one of the most destructive global pandemics
in history
 Influenza
 Spanish: 40-50 million people in 1918
 Asian: 2 million in 1957
 Hong Kong: 1 million in 1968
Who is responsible when an
outbreak occurs?
 World Health Organization (WHO)
 Directing and coordinating authority for health within the
UN system.
 Responsible for providing leadership on global health
matters, research, setting norms and standards,
evidence-based policies, support in assessing health
trends
 “In the 21st century, health is a shared responsibility,
involving equitable access to essential care and collective
defense against transnational threats
 WHO WebQuest
WHO WebQuest Questions
1. Who is the director-general of WHO at the moment?
2. How many countries are involved in WHO?
3. List the 6 regional office locations and the location of WHO
headquarters.
4. What year what WHO formed?
5. List 3 big achievements of WHO and the dates.
6. Explain what “International Health Regulations” is.
7. WHO is funded mainly through what source?
Who is responsible?
 Centers for Disease Control and Prevention (CDC)
 Major operating component of Department of Health and
Human Services
 Protects Americans from all types of diseases
 Explore the CDC website and write a brief summary of the
mission, role, history and accomplishments of the CDC
 Then, find what vaccines are required of all travelers, most
travelers, and some travelers if you and your children are
traveling to India to visit friends/family.
 http://www.cdc.gov/
Then, with a partner, complete the CDC Simulation
 CDC Simulation
Who is responsible?
 Food and Drug Administration (FDA—U.S.)
 Agency within the US Department of Health and
Human Services
 Responsible for:
 Protecting public health through food sources and drug
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safety
Protecting against electronic product radiation
Assuring cosmetics and supplements are safe and properly
labeled
Regulating tobacco products
Advancing public health by helping to speed product
innovations