Transcript ch03

Human Diseases
A Systemic Approach
Sixth Edition
Mary Lou Mulvihill
Mark Zelman
Paul Holdaway
Elaine Tompary
Jill Raymond
Chapter 3
Infectious Diseases
Mulvihill, Zelman, Holdaway, Tompary, and Raymond
Human Diseases: A Systemic Approach, 6e
Copyright ©2006 by Prentice-Hall, Inc.
Upper Saddle River, New Jersey 07458
All rights reserved.
Chapter 3
Infectious Diseases
Multimedia Asset Directory
Slide 12
Slide 27
Slide 34
Slide 35
Pneumonia
Penicillin
Specimen Collection
Sanitation, Disinfection, and Sterilization
Mulvihill, Zelman, Holdaway, Tompary, and Raymond
Human Diseases: A Systemic Approach, 6e
Copyright ©2006 by Prentice-Hall, Inc.
Upper Saddle River, New Jersey 07458
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Bacteria
 Small size, no nucleus or membranous
organelles
 Cell wall
–
–
–
–
Cocci
Bacilli
Spirilla
Vibrios
 Gram-positive
 Gram-negative
Mulvihill, Zelman, Holdaway, Tompary, and Raymond
Human Diseases: A Systemic Approach, 6e
Copyright ©2006 by Prentice-Hall, Inc.
Upper Saddle River, New Jersey 07458
All rights reserved.
Infectious Disease
 Contagious
 Communicable – transmitted from human
to human
 Noncommunicable – not transmitted
directly from humans
Mulvihill, Zelman, Holdaway, Tompary, and Raymond
Human Diseases: A Systemic Approach, 6e
Copyright ©2006 by Prentice-Hall, Inc.
Upper Saddle River, New Jersey 07458
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Figure 3-1: Types of pathogenic organisms include bacteria
(A), viruses (B), protozoa ( C ), and helminths, or worms
(D).
Mulvihill, Zelman, Holdaway, Tompary, and Raymond
Human Diseases: A Systemic Approach, 6e
Copyright ©2006 by Prentice-Hall, Inc.
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Bacterial Reproduction – Illness
 Binary fission
 Endospores – genetic material resistant to
dessication
 Endotoxin – causes life-threatening shock
 Bacteria are able to adapt and survive in a
number of different environments.
Mulvihill, Zelman, Holdaway, Tompary, and Raymond
Human Diseases: A Systemic Approach, 6e
Copyright ©2006 by Prentice-Hall, Inc.
Upper Saddle River, New Jersey 07458
All rights reserved.
Figure 3-2A: Gram-stained bacteria on microscope slide.
Pink rod-shaped cells are Escherichia coli. (Courtesy of the
CDC, 1979.)
Mulvihill, Zelman, Holdaway, Tompary, and Raymond
Human Diseases: A Systemic Approach, 6e
Copyright ©2006 by Prentice-Hall, Inc.
Upper Saddle River, New Jersey 07458
All rights reserved.
Figure 3-2B: Purple cocci are Staphylococus aureus.
(© SIU BioMed/Custom Medical Stock Photo.)
Mulvihill, Zelman, Holdaway, Tompary, and Raymond
Human Diseases: A Systemic Approach, 6e
Copyright ©2006 by Prentice-Hall, Inc.
Upper Saddle River, New Jersey 07458
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Table 3-1: Common Bacterial Pathogens and Associated
Diseases.
Mulvihill, Zelman, Holdaway, Tompary, and Raymond
Human Diseases: A Systemic Approach, 6e
Copyright ©2006 by Prentice-Hall, Inc.
Upper Saddle River, New Jersey 07458
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Normal chest x-ray of clear lungs.
(Courtesy of the CDC.)
Mulvihill, Zelman, Holdaway, Tompary, and Raymond
Human Diseases: A Systemic Approach, 6e
Copyright ©2006 by Prentice-Hall, Inc.
Upper Saddle River, New Jersey 07458
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Lung with bacterial pneumonia in lower right lobe. Bacterial
infection has caused the air space to fill with pus and fluid.
(Courtesy of the CDC.)
Mulvihill, Zelman, Holdaway, Tompary, and Raymond
Human Diseases: A Systemic Approach, 6e
Copyright ©2006 by Prentice-Hall, Inc.
Upper Saddle River, New Jersey 07458
All rights reserved.
Click on the screenshot to view a video on the topic of
pneumonia.
Mulvihill, Zelman, Holdaway, Tompary, and Raymond
Human Diseases: A Systemic Approach, 6e
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Copyright ©2006 by Prentice-Hall, Inc.
Upper Saddle River, New Jersey 07458
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Virus
 Core genetic material (RNA or DNA)
enclosed in a capsid
 Does not independently grow, metabolize
or reproduce
 Carries out life processes by entering cells
and directing energy, materials and
organelles or by causing cells to lyse
 Responsible for acute, and latent
infections
Mulvihill, Zelman, Holdaway, Tompary, and Raymond
Human Diseases: A Systemic Approach, 6e
Copyright ©2006 by Prentice-Hall, Inc.
Upper Saddle River, New Jersey 07458
All rights reserved.
Figure 3-3: Structure of an enveloped virus.
Mulvihill, Zelman, Holdaway, Tompary, and Raymond
Human Diseases: A Systemic Approach, 6e
Copyright ©2006 by Prentice-Hall, Inc.
Upper Saddle River, New Jersey 07458
All rights reserved.
Table 3-2: Viral Pathogens and their Diseases.
Mulvihill, Zelman, Holdaway, Tompary, and Raymond
Human Diseases: A Systemic Approach, 6e
Copyright ©2006 by Prentice-Hall, Inc.
Upper Saddle River, New Jersey 07458
All rights reserved.
Protozoa
 Eukaryotic microorganisms
 Larger than bacteria with complex internal
structures
 Classified as amoeboids, flagellates,
cilates, and sporozoans
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Human Diseases: A Systemic Approach, 6e
Copyright ©2006 by Prentice-Hall, Inc.
Upper Saddle River, New Jersey 07458
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Figure 3-4: The human hookworm lifecycle.
Mulvihill, Zelman, Holdaway, Tompary, and Raymond
Human Diseases: A Systemic Approach, 6e
Copyright ©2006 by Prentice-Hall, Inc.
Upper Saddle River, New Jersey 07458
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Fungi
 Multicelled organisms
 Contain polysaccharide – Chitin
 Reproductive structures – spores
 Cause disease by interfering with normal
organ structure and function or by
inflammation or allergy
Mulvihill, Zelman, Holdaway, Tompary, and Raymond
Human Diseases: A Systemic Approach, 6e
Copyright ©2006 by Prentice-Hall, Inc.
Upper Saddle River, New Jersey 07458
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Helminths
 Roundworms, flatworms
 Well developed reproductive systems
 Complex lifecycle
 Infections are called infestations
Mulvihill, Zelman, Holdaway, Tompary, and Raymond
Human Diseases: A Systemic Approach, 6e
Copyright ©2006 by Prentice-Hall, Inc.
Upper Saddle River, New Jersey 07458
All rights reserved.
Roundworms
 Round in cross section
 Include: filarial (infect lymphatics), large
(infect the intestines)
 Examples: Ascaris, Enerobius
Mulvihill, Zelman, Holdaway, Tompary, and Raymond
Human Diseases: A Systemic Approach, 6e
Copyright ©2006 by Prentice-Hall, Inc.
Upper Saddle River, New Jersey 07458
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Flatworms
 Flattened bodies examples: Schistosoma
Taenia
 Cause disease by using host nutrients or
by feeding on host blood causing anemia
and severe inflammatory responses
Mulvihill, Zelman, Holdaway, Tompary, and Raymond
Human Diseases: A Systemic Approach, 6e
Copyright ©2006 by Prentice-Hall, Inc.
Upper Saddle River, New Jersey 07458
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Arthropod Vectors
 Ticks, mites, lice, flies, mosquitoes, and
fleas
 Transmit pathogenic microorganisms to
humans
 Example: plasmodium
 Animals act as reservoirs – source of the
pathogen; example: rabies
Mulvihill, Zelman, Holdaway, Tompary, and Raymond
Human Diseases: A Systemic Approach, 6e
Copyright ©2006 by Prentice-Hall, Inc.
Upper Saddle River, New Jersey 07458
All rights reserved.
Epidemiology
and Transmission
 Epidemiology – study of transmission,
occurrence, distribution, and control of
disease
 Horizontal transmission – infected human
to susceptible human
 Vertical transmission – infection from one
generation to the next
Mulvihill, Zelman, Holdaway, Tompary, and Raymond
Human Diseases: A Systemic Approach, 6e
Copyright ©2006 by Prentice-Hall, Inc.
Upper Saddle River, New Jersey 07458
All rights reserved.
Distribution and Frequency
 Incidence – number of new cases
 Prevalence – number of existing cases
 Endemic – exists in low levels
 Pandemic – infection spreads to large
numbers
 Outbreak – sudden occurrence in
unexpected numbers within a limited area
Mulvihill, Zelman, Holdaway, Tompary, and Raymond
Human Diseases: A Systemic Approach, 6e
Copyright ©2006 by Prentice-Hall, Inc.
Upper Saddle River, New Jersey 07458
All rights reserved.
Treatment
 Antibacterials
 Antivirals
 Antifungals
 Supportive care for inflammation, pain,
and fever
Treatment must be targeted and
specific to avoid antimicrobial
resistance
Mulvihill, Zelman, Holdaway, Tompary, and Raymond
Human Diseases: A Systemic Approach, 6e
Copyright ©2006 by Prentice-Hall, Inc.
Upper Saddle River, New Jersey 07458
All rights reserved.
Antibiotics – Mechanism of Action
 Target bacterial cell wall
 Target cell membrane
 Inhibit protein synthesis targets in bacterial
machinery
 Interfere with bacterial metabolism, DNA,
and RNA synthesis
Mulvihill, Zelman, Holdaway, Tompary, and Raymond
Human Diseases: A Systemic Approach, 6e
Copyright ©2006 by Prentice-Hall, Inc.
Upper Saddle River, New Jersey 07458
All rights reserved.
Click on the screenshot to view an animation showing
penicillin.
Mulvihill, Zelman, Holdaway, Tompary, and Raymond
Human Diseases: A Systemic Approach, 6e
Return to Directory
Copyright ©2006 by Prentice-Hall, Inc.
Upper Saddle River, New Jersey 07458
All rights reserved.
Antivirals
 Nucleic acid analogues mimic correct DNA
or RNA bases.
 Interfere with assembly of new virus
particles within the cell or interfere with the
attachment of viruses to host cells
Reduces the number of viruses reproduced
Mulvihill, Zelman, Holdaway, Tompary, and Raymond
Human Diseases: A Systemic Approach, 6e
Copyright ©2006 by Prentice-Hall, Inc.
Upper Saddle River, New Jersey 07458
All rights reserved.
Antifungals
 Target cell walls and membranes
 Affect human cells, therefore may be toxic
Mulvihill, Zelman, Holdaway, Tompary, and Raymond
Human Diseases: A Systemic Approach, 6e
Copyright ©2006 by Prentice-Hall, Inc.
Upper Saddle River, New Jersey 07458
All rights reserved.
Antiprotozoals
 Interfere with protein synthesis and
metabolism
 Sensitive to medications that paralyze
protozoal muscles or interfere with
carbohydrate metabolism
 Resistant microorganisms evolve,
rendering existing treatments useless
Mulvihill, Zelman, Holdaway, Tompary, and Raymond
Human Diseases: A Systemic Approach, 6e
Copyright ©2006 by Prentice-Hall, Inc.
Upper Saddle River, New Jersey 07458
All rights reserved.
Vaccination
 The presentation of antigens from a
microorganism to provoke an immune
response
 Contain dead bacterial, extracted
antigens, inactivated toxins, viral particles,
or genetically engineered proteins
 Have been used to eliminate disease
Mulvihill, Zelman, Holdaway, Tompary, and Raymond
Human Diseases: A Systemic Approach, 6e
Copyright ©2006 by Prentice-Hall, Inc.
Upper Saddle River, New Jersey 07458
All rights reserved.
Table 3-3 Universally recommended vaccinations
Mulvihill, Zelman, Holdaway, Tompary, and Raymond
Human Diseases: A Systemic Approach, 6e
Copyright ©2006 by Prentice-Hall, Inc.
Upper Saddle River, New Jersey 07458
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Emerging Infectious Disease
 Tuberculosis
 Antibiotic resistance
 Changes in climate, urbanization,
crowding, increased incidence of chronic
disease, fast world travel, disruption of
social government structure
Mulvihill, Zelman, Holdaway, Tompary, and Raymond
Human Diseases: A Systemic Approach, 6e
Copyright ©2006 by Prentice-Hall, Inc.
Upper Saddle River, New Jersey 07458
All rights reserved.
Click on the screenshot to view a video showing how to
collect specimens.
Mulvihill, Zelman, Holdaway, Tompary, and Raymond
Human Diseases: A Systemic Approach, 6e
Return to Directory
Copyright ©2006 by Prentice-Hall, Inc.
Upper Saddle River, New Jersey 07458
All rights reserved.
Click on the screenshot to view a video on the topic of
sanitation, disinfection, and sterilization.
Mulvihill, Zelman, Holdaway, Tompary, and Raymond
Human Diseases: A Systemic Approach, 6e
Return to Directory
Copyright ©2006 by Prentice-Hall, Inc.
Upper Saddle River, New Jersey 07458
All rights reserved.