1.1 Infectious Disease Flashcards
Infectious disease
- AKA Communicable disease
- An illness caused by a specific infectious agent or its toxic product
Factors Affecting the Immune System
- Pregnancy
- Pre-existing conditions
- Malignancies or immunosuppressive diseases (cancer, HIV)
- Stress (emotional or surgical)
- Malnutrition
- Age
- Chronic diseases
- Lymph node dissection
- Immunosuppressive treatment (corticosteroids, chemo, radiation, anti-rejection drugs)
- Indwelling lines and tubes
- Presence of implanted medical devices
- Obesity
Specific Infectious Agents
- Viruses
- Bacteria
- Fungi
- Parasites
- Prions
Virus definition
Subcellular organism made up only of a ribonucleic acid (RNA) or a deoxyribonucleic acid (DNA) covered w/proteins
Characteristics of viruses
- Rapid replication
- High mutation rates
- Self-limiting
Are antibiotics effective on viruses?
No, only on bacteria
What viral infections have antiviral drugs available for treatment?
- Herpes
- Hepatitis
- Influenza
- HIV
Are antiviral drugs subject to resistance?
Yes
Bacteria definition
Single-celled microorganism with well defined cell walls that can grow independently on artificial media without the need for other cells
How are bacteria classified?
- Shape
- Need for oxygen
Bacteria classification by shape
- spherical
- rod
- spiral
- comma
- corkscrew
spherical
cocci
rod
bacilli
spiral
spirilla
comma
vibrios
corkscrew
spirochaetes
Bacteria classification by need for oxygen
- Aerobic
- Anaerobic
Bacteria constitute what percentage of human pathogens
38%
Are bacterial infections treatable by antibiotics?
Yes, but…
- Occasionally need labs to determine specificity of antibiotic resistance (gram stain)
- High emergence of antibiotic-resistant bacterial strains
Fungi definition
Single-celled or multicellular organism
Forms of fungi
- True pathogen
- Opportunistic pathogen
True pathogen
causes infections in healthy persons
Opportunistic pathogen
causes infections in
immunocompromised persons
Yeast
a common fungus causing thrush, diaper rash, & athlete’s foot
Uses of fungi
development of antibiotics, antitoxins, & other drugs
Treatment of fungal infection
antifungals or antivirals applied directly to the skin or injected in the
case of serious infection