1. Chapter 5 Disease and Disease-Producing Organisms

2. Overview

3. Key Terms
acute etiology prion antibiotic fungus prognosis antiseptic helminth protozoa arthropod host sign asepsis infection sterilization bacteria microbiome symptom chronic microorganism syndrome diagnosis nosocomial infection systemic disease opportunistic infection therapy disinfectant pandemic toxin endemic parasite vector endospore pathogen virulence epidemic pathophysiology virus

4. Chapter 5 Key Ideas
Chapter 5 introduces the key idea of causation and correlation
Establishing causation is critical for preventing and treating diseases.
Confusing correlation with causation has significant societal impacts.

5. Studies of Disease #1 Learning Objectives
Define disease, and list seven categories of disease.
Explain the meaning of a predisposing cause of disease, and list seven such causes.
Describe the science of epidemiology, and cite some types of studies done in that field.

6. Disease Diagnosis, Treatment, and Prevention #1
Learning Objectives (cont.)
Define terms used in the diagnosis and treatment of disease.
Define complementary and alternative medicine; cite four alternative or complementary fields of practice.

7. Infectious Disease #1 Learning Objectives (cont.)
Explain methods by which microorganisms can be transmitted from one host to another.

8. Microbiology: The Study of Microorganisms #1
Learning Objectives (cont.)
Name four types of microorganisms, and give the characteristics of each.
Define microbiome, and explain its value.
List some diseases caused by each type of microorganism.

9. Multicellular Pathogens #1
Learning Objectives (cont.)
Name two categories of parasitic worms, and give examples of each.
Explain the role of parasitic arthropods in causing disease.

10. Microbial Control #1 Learning Objectives (cont.)
Give four reasons for the emergence and spread of microorganisms today.
Describe four public health measures taken to prevent the spread of disease.
Differentiate between sterilization and disinfection, and give three examples of each.
List the measures included as part of body substance precautions.
Name two types of antimicrobial agents, and give three examples of each.

11. Laboratory Identification of Pathogens #1
Learning Objectives (cont.)
Describe three methods used to identify microorganisms in the laboratory.

12. Learning Objectives (cont.)
Case Study #1
Learning Objectives (cont.)
Using the case study, describe a virus’s mechanism of infection and the host’s response.

13. Word Anatomy #1
Learning Objectives (cont.)
Show how word parts are used to build words related to disease.

14. Studies of Disease #2 Disease
Abnormality of structure or function of part, organ, or system
May be felt or observed by others.
May have a known or unknown cause.
Severity of effects may be variable.

15. Disease Categories Infection Degenerative diseases
Nutritional diseases
Metabolic disorders
Immune disorders
Neoplasms
Psychiatric disorders
FIGURE 5-1 Rheumatoid arthritis (autoimmune disorder).

16. Contributing Causes of Disease
Age
Gender
Heredity
Living conditions and lifestyles
Emotional disturbance
Physical and chemical damage
Preexisting illness

17. Epidemiology The study of the cause of disease in populations
Disease statistics
Incidence rate
Prevalence rate
Mortality rate
Disease categories
Epidemic
Endemic
Pandemic
FIGURE 5-2 The influenza pandemic.

18. Studies of Disease (Review)
Checkpoints
5-1 What is disease?
5-2 Name several categories of disease.
5-3 What is the definition of a predisposing cause of disease?
5-4 List several predisposing causes of disease.
5-5 Identify three types of statistics typically collected by epidemiologists. ✓

19. Disease Diagnosis, Treatment, and Prevention #2
Learning Objectives
Define terms used in the diagnosis and treatment of disease.
Define complementary and alternative medicine; cite four alternative or complementary fields of practice.

20. Important Terms Symptoms Signs Syndrome Disease classification Acute
Chronic
Subacute
Prognosis

21. Treatment Types Medication Surgery Physical therapy
Occupational therapy
Respiratory therapy
Nutritional therapy
Counseling and support groups
FIGURE 5-3 Physical therapy.

22. Complementary and Alternative Medicine
May be used with or instead of conventional medicine
Naturopathy
Chiropractic
Acupuncture
Biofeedback
Massage
Yoga
Meditation
Herbal remedies

23. Disease Prevention
Healthy lifestyle choices can reduce the incidence and severity of disease
Stop smoking.
Limit alcohol use.
Eat a healthy diet.
Maintain a healthy weight.
Get regular exercise.
Health promotion organizations
The WHO
The CDC

24. Disease Diagnosis, Treatment, and Prevention (Review)
Checkpoints
5-6 What is the identification of an illness called?
5-7 What is a symptom? A sign? ✓

25. Infectious Disease #2 Learning Objectives
Explain methods by which microorganisms can be transmitted from one host to another.

26. Infectious Disease Terms
Pathogens
Microorganisms
Parasites
Infection
Local
Systemic
Modes of transmission
Direct
Indirect

27. Portals of Entry Skin (especially if it is damaged) Respiratory tract
Digestive system
Urinary and reproductive systems

28. Infectious Disease (Review)✓
Checkpoints
5-8 What is the relationship between a parasite and a host?
5-9 What is a communicable disease?
5-10 What term describes any disease-causing organism?
5-11 What are some portals of entry and exit for microorganisms?

29. Microbiology: The Study of Microorganisms #2
Learning Objectives
Name four types of microorganisms, and give the characteristics of each.
Define microbiome, and explain its value.
List some diseases caused by each type of microorganism.

30. Medically Relevant Microorganisms
Type of Organisms
Name of Study
Characteristics of Organism
Representative Examples
Bacteria
Bacteriology
Simple, single-cell organisms.
Grow in many environments.
Lack a true nucleus and most organelles
Staphylococcus
Viruses
Virology
Composed of nucleic acid (DNA or RNA) and protein. Can reproduce only within living cells—obligate intracellular parasites
Ebola
Fungi
Mycology
Very simple, nongreen, plantlike organisms. Single-cell, globular forms are yeasts; multicellular filamentous forms are molds
Candida
Protozoa
Protozoology
Single-cell, animal-like organisms
Giardia

31. Microbiome
Population of beneficial microorganisms (bacteria, fungi) that normally grows on and within the human body
Advantages
Prevents infection by pathogenic microbes
Synthesizes nutrients
Promotes immune tolerance
Disruptions of microbiome cause disease

32. Bacteria Bacteria Single-celled organisms Lack a true nucleus
Found everywhere
Types
Anaerobic (live in oxygen-free environments)
Aerobic (oxygen necessary for life)
Facultative anaerobes (oxygen optional for life)

33. Bacterial Specializations
Endospores
Flagella
Pili: short flagella- like structures
FIGURE 5-4 Endospores.
FIGURE 5-5 Flagella.

34. Naming Bacteria Genus name: Capitalized and italic
Species name: Lowercase and italic
Example: Escherichia coli or E. coli

35. Types of Bacteria Cocci Bacilli Vibrios Spirilla Spirochetes
Rickettsia
Chlamydiae

36. Cocci

37. Bacilli

38. Curved Rods
What feature indicates that the cells in A are capable of movement?

39. ✓ Bacteria (Review) Checkpoints
5-12 What categories of organisms are studied in microbiology?
5-13 What term refers to microorganisms that normally live in or on the body?
5-14 What are resistant forms of bacteria called?
5-15 What are the three basic shapes of bacteria?
Bacteria (Review) ✓

40. Viruses
Composed of a core of nucleic acid surrounded by a coat of proteins
Grow only within living cells

41. Relative Size of Microorganisms
FIGURE 5-9 Virus size comparison.

42. Infectious Proteins: Prions
Composed solely of protein
Cause Creutzfeldt-Jakob disease (humans) and mad cow disease

43. Fungi Simple plantlike organisms; few are pathogenic
Yeasts: single-celled forms (e.g., Candida)
Molds: fuzzy, filamentous forms
Yeasts Molds Candida infection

44. Protozoa Animal-like, single-celled microbes found all over the world
Types
Amebas
Ciliates
Flagellates
Apicomplexans

45. Parasitic Protozoa

46. Microorganisms (Review)
Checkpoints
5-16 How do viruses differ from bacteria?
5-17 What type of organism causes a mycotic infection?
5-18 What group of microorganisms is most animal- like? ✓

47. Multicellular Pathogens #2
Learning Objectives
Name two categories of parasitic worms, and give examples of each.
Explain the role of parasitic arthropods in causing disease.

48. Parasitic Worms FIGURE 5-14 Filarial worm infestation (elephantiasis).
Multicellular parasite invasion is called an infestation
Helminthology: The study of parasitic worms
Types
Roundworms
Ascaris
Pinworms
Hookworms
Filarial worms
Flatworms
FIGURE 5-14 Filarial worm infestation (elephantiasis).

49. Parasitic Roundworms

50. Parasitic Flatworms Ribbon-like or leaf-shaped A. Tapeworm
B. Tapeworm segment
C. Fluke

51. Parasitic Arthropods Includes insects and spiders
Some arthropods serve as disease vectors
Few arthropods cause infestations
A. Young hair louse emerging from egg (nit)
B. Adult hair louse
C. Scabies mite

52. Multicellular Parasites (Review)
Checkpoints
5-19 What is the study of worms called?
5-20 Name two types of arthropods. ✓

53. Microbial Control #2 Learning Objectives
Give four reasons for the emergence and spread of microorganisms today.
Describe four public health measures taken to prevent the spread of disease.
Differentiate between sterilization and disinfection, and give three examples of each.
List the measures included as part of body substance precautions.
Name two types of antimicrobial agents and give three examples of each.

54. Factors Contributing to Increased Infections
Increase in world population
Disruption of animal habitats
Increased travel (SARS)
Opportunistic infections
Changes in food handling

55. Public Health Measures
Sewage and garbage disposal
Water purification
Prevention of food contamination
Pasteurization

56. Aseptic Methods
Kills every Kills most Disinfection of living organism living organisms living surfaces

57. Infection Control Techniques
Body substance precautions
Change gloves between patients
Wear protective coverings
Treat all waste as contaminated waste
Dispose sharps in puncture-proof containers
Do not recap needles
Handwashing is the MOST IMPORTANT MEASURE for preventing microbial spread

58. Antimicrobial Agents Antibiotics: treat bacterial infections
Must use sparingly to reduce the development of antibiotic-resistant strains
Antiviral agents
Block removal of protein coat of virus
Block production of viral nucleic acid
Block enzyme production needed to create new virus particles

59. Microbial Control (Review)
Checkpoints
5-21 What are the two levels of asepsis?
5-22 What is the single most important measure for preventing the spread of infection?
5-23 What is an antibiotic? ✓

60. Laboratory Identification of Pathogens #2
Learning Objectives
Describe three methods used to identify microorganisms in the laboratory.

61. Laboratory Identification of Pathogens #3
Obtain and label specimens from patients.
Grow out bacterial cells.
Isolate individual organisms.
Multiply to form colonies.
Stain cells so they can be seen.
Perform tests to identify organisms.
FIGURE 5-18 Bacterial colonies.
FIGURE 5-19 Gram staining.
Gram-positive Gram-negative
diplococci bacilli

62. Other Methods of Identification
Growth characteristics in liquid and solid media
Oxygen requirements
Ability of bacteria to utilize various carbohydrates
Reaction to various chemicals
Serologic (immunologic) tests

63. Laboratory Identification of Pathogens (Review)
Checkpoints
5-24 What are the dyes used to color microorganisms called? ✓

64. Case Study #2 Learning Objectives
Using the case study, describe a virus’s mechanism of infection and the host’s response.

65. Case Study #3 Virus’s Mechanism of Infection Enter host cell.
Trick host into transcribing viral mRNA.
Trick host into translating the mRNA into viral protein.
Make new virus.
Host’s Response
Increase body temperature to slow viral replication.
Activate the immune system to seek out and destroy virus.

66. Case Study: Review Casepoints
5-1 Why is the influenza infection that attacked Maria in the opening case study considered to be epidemic?
5-2 Which of the these classifications applies to Maria’s disease: acute, chronic, or subacute?
5-3 What evidence is there in Maria’s case study to show that her influenza infection was communicable?
5-4 What was the portal of entry for Maria’s infection?

67. Case Study: Review (Part 2)
Casepoints
5-5 What type of nucleic acid characterizes the virus that infected Maria?
5-6 What steps could Maria have taken to prevent her influenza infection?
5-7 Would antibiotics have helped Maria to overcome her infection? Why or why not?

68. Word Anatomy #2
Learning Objectives
Show how word parts are used to build words related to disease.

69. Word Anatomy #3 Word Part Meaning Example Studies of Disease iatro-
physician, medicine
An iatrogenic disease results from the adverse effects of treatment.
idio-
self, separate, distinct
An idiopathic disease has no known cause.
pan-
all
A pandemic disease is prevalent throughout an entire country, continent, or the world.
pre-
before
A predisposing cause enters into production of disease.
psych/o
mind
The medical field of psychiatry specializes in treatment of mental disorders.
Disease Diagnosis, Treatment, and Prevention
chir/o
hand
Chiropractic treatment involves use of the hands for manipulation to correct misalignment of the body.
syn-
Together
A syndrome is a group of symptoms and signs that together characterize a disease.

70. Word Anatomy #4 Word Part Meaning Example Infectious Disease aer/o
air, gas
An aerobic organism requires air (oxygen) to grow.
an-
absent, deficient, lack of
An anaerobic organism does not require air (oxygen) to grow.
diplo-
double
Diplococci are round bacteria arranged in pairs.
myc/o
fungus
Mycology is the study of fungi.
py/o
pus
The species name pyogenes indicates that an organism produces pus.
staphylo-
grapelike cluster
Staphylococci are bacteria in clusters.
strepto-
chain
Streptococci are arranged in chains.
tox/o
poison
Bacteria can harm the body by producing toxins.

71. Word Anatomy #5 Word Part Meaning Example Microbial Control -cide
kill or destroy
A bactericide is an agent that kills bacteria.
septic
poison, rot, decay
Aseptic methods are used to kill or prevent the growth of microorganisms.
circum-
around
Circumduction is movement around a joint in a circle.

72. Additional Information