Host-Parasite Relationship

1
Host-Parasite Relationship

• Normal Flora
• Pathogens
• Infections
• Opportunistic
• pathogens

2
Skin Flora

• 180 species
• Streptococcus
• Staphylococcus
• Propionibacterium
• Body Odor
• Acne

3
Oral Cavity Flora

• Plaque
• Anaerobes
• Biofilms
• Dental Caries
• Streptococcus mutans, sobrinus
• Sucrose

4
Tongue
5
Intestinal Tract

• Small Intestine
• Enterococci,
• Lactobacilli

• Stomach pH
• Helicobacter pylori

6
Large intestine

• 1010-1011 cells/gm
• Bacteroides
• Enterobacteria

• Escherichia coli
• Enterococcus

7
Large Intestine Flora

• Methanogens
• Food passage 24 hrs
• Excrete 1013/day
• Probiotics
• Fecal transplant

8
Respiratory Tract

• Staphylococcus aureus
• Streptococcus pneumoniae
• S. pyogenes
• Corynebacterium diphtheriae
• Carrier

9
Urogenital Tract
Opportunistic Pathogens E. coli Virulence Invasive
ness Toxicity Lactobacillus acidophilus
10
Adherence

• Specific Adherence
• Capsule
• Slime Layer
• Glycocalyx
• Fimbriae
• Pili - longer

11
Invasiveness

• Colonization Factor Antigen
• Invasion
• Colonization
• Iron- Siderophore
• Bacteremia vs. Septicemia

12
Enzymes Toxins

• Coagulase
• Collagenase
• Exotoxins
• Cytolytic Toxins
• Hemolysins, Leukocidins
• Diphtheria Toxin
• Botulism Toxin
• Tetanus Toxin

Tetanus
13
Other Toxins
Enterotoxin Cholera toxin Endotoxin
Pyrogen LD50 Virulence Factors Attenuated Strains
Pyrogen free Products
14
Virulence Factors
15
Nonspecific Host Defense

• Natural Resistance
• Age
• Stress
• Diet
• Anatomical Defenses
• Skin, Stomach, Tears

16
Compromised Hosts Inflammation Fever Nosocomial
Infections
17
Host-Parasite Word List
Stomach pH2 Helicobacter pylori Small
Intestine Enterococci, Lactobacilli Large
Intestine 1010- 1011 cells/gram
Normal Flora Pathogens Infection Skin
Flora Staphylococcus, Propionibacterium
Oral Cavity Flora Plaque Streptococcus
spp Dental Caries Streptococcus mutans Intestinal
Tract
18
Host-Parasite Word List 2
1010- 1011 cells/gram Bacteroides,
Enterobacteria, Escherichia coli,
Enterococcus Respiratory Tract Staphylococcus
aureus,
Streptococcus pneumoniae, S. pyogenes,
Corynebacterium diphtheriae Carrier Urogenital
Tract
Opportunistic Pathogens Virulence Invasiveness,
Toxicity Specific Adherence
19
Host-Parasite Word List 3
Capsule, Glycocalyx, Slime Layer Fimbriae,
Pili Colonization Factor Antigen
Enzymes Toxins Coagulase, Collagenase Exotoxins
Cytolytic Toxins Hemolysins, Leukocidins
Invasion Colonization Iron Siderophore Bacteremi
a Septicemia
20
Host-Parasite Word List 4
Endotoxin LD50 Attenuated Nonspecific Host
Defenses Natural Resistance
Natural Resistance Age, Stress, Diet Anatomical
Defenses Skin, Stomach, Tears
Diphtheria Toxin Botulism Toxin Tetanus
Toxin Enterotoxin Cholera Toxin
21
Host-Parasite Word List 5
Compromised Host Inflammation Fever