Transcript The Sociology of Infectious Disease: Using Middle School

Introduction to Infectious Disease
Infectious Disease – Key Terms
• Infectious – can spread
• Disease – an abnormal condition affecting the
body of an organism
• Pathogens – “germs”; what causes disease
Germ Theory through the Ages
Germ Theory – states that diseases are caused by microorganisms
Before
Before Germ Theory…
• Theory of “Spontaneous Generation” – diseases were simply an
unfortunate occurrence due to chance & probability
Think about it….
Significant Historical Developments
in Infectious Disease & Germ
Theory
Anton van Leeuwenhoek
• First microbiologist; Dutch; 1670s
• Used microscopes to observe and
identify microscopic living organisms
Ignaz Semmelweis
• Vienna, 1840s
“Childbirth fever”
Louis Pasteur
• France, 1859 – Curved Flask Experiment
• Essentially the definitive demonstration negating
spontaneous generation
Joseph Lister
• Lister, 1860s: Antiseptics
• Washed wounds to
prevent infections during
surgery
Taxonomy and Infectious Disease
• What types of pathogens cause infectious diseases?
• In what taxonomic kingdoms are they classified?
Taxonomy and Infectious Disease
Archaebacteria
Prokarya
Eubacteria
Protista
Eukarya
Fungi
Autotrophic
Plantae
Animalia
Pathogen 1: Bacteria
• Living
– Kingdom Eubacteria (although only a small
fraction of this kingdom are pathogenic)
• Structure
Examples
– Prokaryotic cells
– Produce toxins that harm host (parasitic)
Pathogen 2: Viruses
• Non-living!!!!
– Infect host and take
over cellular
metabolism to
construct new
viruses
• Structure:
– DNA or RNA core
– Contained in protein
capsid
– Protein spikes to
attach to host cells
– Some have a
membranous
envelope
– Shape can vary but
all viruses are
typically symmetrical
Examples: HIV, Influenza, Ebola, Chickenpox
Pathogen 3: Fungi
• Living – Kingdom Fungi
• Structure:
– Eukaryotic
– Chitin cell wall
– Heterotrophic (by absorbing nutrients from host)
• Examples: Ringworm, Yeast Infections, Athlete’s Foot
Pathogen 4: Parasites
• Living – Kingdoms Protista & Animalia
• Structures:
– Protozoans – single celled organisms
– Helminthes – worms
– Animal structures – mosquitoes, fleas, ticks
• Transmitted through ingestion of eggs & insect
bites
• Examples: Malaria, Tapeworm, Bubonic Plague
Pathogen 5: Prions
• Non-living
• Structure
– Misfolded proteins
that cause brain and
neural damage,
eventually fatal
• Examples: Mad Cow
Disease, CreutzfeldtJakob Disease (CJD)
Classroom Activity:
“History-Altering” Infectious Diseases
1. Your group will be assigned 1 infectious disease that altered history.
2. Research that disease with your group on www.cdc.gov or other reliable
sources about one of the following diseases:
• Smallpox in Native American populations during Age of
Exploration/Colonialism
• Tuberculosis in Industrial Revolution age (“The Great White Plague”),
• Bubonic Plague in Europe (“Black Death”)
• Cholera in England (England 1800s),
• Yellow fever in the Panama Canal,
• Typhus (body lice) during the Thirty Years War
• Polio in late 19th-early 20th century;
• Biology/plant life extension: potato blight (cause of the Irish potato famine),
• 1918 influenza in America (“Great Influenza” “Spanish flu” “Flu of 1918”)
• H1N1 Bird flu
• Swine flu