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Principles of Medical Microbiology
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Principles of Infectious Disease:
The Host-Parasite Relationship
Colonization, Normal Microbiota & Symbiotic
Relationships
Pathogenicity and Virulence
Mechanisms of Pathogenicity
Epidemiology
Mechanisms of Immunity
Beneficial
Harmful
Manipulated
Antimicrobial Chemotherapy
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Principles of Infectious Disease
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The Host-Parasite Relationship
Colonization and Normal Microbiota
Permanent residents, transients and opportunists
Symbiotic Relationships
Mutualism, Commensalism, Parasitism
Pathogenicity and Virulence
Evolution of parasitism
Attenuation of virulence
The Infectious Process:
1) Exposure: Oral, respiratory, parenteral, etc
2) Attachment: Pili, capsules, proteins, etc
3) Colonization: Metabolism, replication, avoid clearance
4) Tissue Damage: Toxins, invasiveness, immune response
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Principles of Infectious Disease





The Host-Parasite Relationship
Colonization and Normal Microbiota
Permanent residents, transients and opportunists
Symbiotic Relationships
Mutualism, Commensalism, Parasitism
Pathogenicity and Virulence
Evolution of parasitism
Attenuation of virulence
The Infectious Process:
1) Exposure: Oral, respiratory, parenteral, etc
2) Attachment: Pili, capsules, proteins, etc
3) Colonization: Metabolism, replication, avoid clearance
4) Tissue Damage: Toxins, invasiveness, immune response
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Colonization
Normal
Microbiota
Principles of Infectious Disease
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The Host-Parasite Relationship
Colonization and Normal Microbiota
Permanent residents, transients and opportunists
Symbiotic Relationships
Mutualism, Commensalism, Parasitism
Pathogenicity and Virulence
-Evolution of parasitism
-Attenuation of virulence
The Infectious Process:
1) Exposure: Oral, respiratory, parenteral, etc
2) Attachment: Pili, capsules, proteins, etc
3) Colonization: Metabolism, replication,
avoidance of immune clearance
4) Tissue Damage: Toxins, invasiveness,
adverse immune response
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Routes of
Exposure
Attachment
Colonization
Avoiding the
Immune
Response
Avoiding the
Immune
Response
Tissue Damage:
Invasiveness
Tissue
Damage:
Invasion
Tissue
Damage:
The Action
of Exotoxins
Epidemiology
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Reservoirs of Agents
Humans, Animals, Inanimate, Nosocomial
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Transmission of Agents
Contact, Vectors, Vehicles
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Disease Categories
Infectious vs contagious; Chronological sequence;
Geographical distribution; Incidence rates;
Extent of involvement; Agents; Clinical nature
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Nosocomial
Infections
Transmission:
How the
Microorganisms
Spread
Portals of Entry:
How the agents
enter the body
Incidence
Emerging Diseases
The Immune System
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Functions of the Immune System
Types of Immune Responses
Organization of the Immune System
Innate Defense Mechanisms
Acquired Defense Mechanisms
Applied Immunology
A macrophage
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The Immune System
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Functions of the Immune System
Defense – Recognition of…
Homeostasis – Recognition of…
Surveillance – Recognition of…
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Types of Immune Responses
Humoral – Transferred by…
Cellular – Transferred by…
Innate – First and second line defenses
Acquired – “Antigen driven” third line defenses
Recognition, Specificity, Memory
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Organization of the Immune System
Innate Defense Mechanisms
Acquired Defense Mechanisms
Applied Immunology
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Epithelial Barriers
Chemical
Barriers
The Immune System
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Functions of the Immune System
Types of Immune Responses
Organization of the Immune System
Cells:
Phagocytes: Neutrophils, macrophages, APC’s
Antigen responsive cells: B and T cells
Tissues:
Primary: Bone marrow, thymus
Secondary: Lymph nodes, spleen, diffuse lymphoid tissue
Molecules:
Enzymes, interferons, complement, interleukins, antibody
Innate Defense Mechanisms
Acquired Defense Mechanisms
Applied Immunology
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Hematopoiesis
Tissues
The Immune System
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Functions of the Immune System
Types of Immune Responses
Organization of the Immune System
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Innate Defense Mechanisms
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Phagocytosis
Inflammation
Interferon
Complement
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Acquired Defense Mechanisms
Applied Immunology
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Distribution of
Phagocytic
Cells
Phagocytosis
Inflammation
Interferon
C’
The Immune System
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Functions of the Immune System
Types of Immune Responses
Organization of the Immune System
Innate Defense Mechanisms
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Acquired Defense Mechanisms
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-Humoral vs cellular specific immunity
-The nature of antigens
-The nature of antibodies
-The functions of antibodies
-Clonal selection
-Humoral (antibody) immune responses
-Cellular immune responses
-Natural killer cells
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Applied Immunology
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Antigens
Antibodies
Functions of
Antibodies
Passive Transfer of Antibody
Clonal
Selection
Antibody Production
Immunity:
-APC’s
-Ag Processing
-Il-1 Production
-Ag Presentation
-Th Activation
-Il-2 Production
-Th Development
-Th1 and CMI
-Th2 and Antibody
-Tc Developement
-Tc Killing
The Immune System
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Functions of the Immune System
Types of Immune Responses
Organization of the Immune System
Innate Defense Mechanisms
Acquired Defense Mechanisms
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Applied Immunology
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-Methods of acquiring immunity
-Vaccination
-Immunological-based testing:
ELISA assays
-Clinical immunology
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Figure 17.1
Antimicrobial Chemotherapy
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History
Ancient, Ehrlich, Domagck
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Terminology
Antibiotics, Synthetic antibiotics, Semi-synthetic antibiotics
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Properties of Antibiotics
Selective toxicity, Therapeutic index, Spectrum of activity
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Adverse Reactions
Toxicity, Allergy, Disrupt normal microbiota, Resistance
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The Ideal Antibiotic
Mechanism of Action
Bacteria, Viruses, Fungi, Protozoa, Helminths
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