Pathogens and pathogenesis Flashcards
Candida Albicans Mortality rate
40%
Candida Albicans systemic infections/year
400,000
Aspergillus Mortality rate
80%
Aspergillus Systemic infections/year
200,000
Cryptococcus Mortality rate
40%
Cryptococcus Systemic infections
1,000,000
Why are fungal infections increasing?
Medical Advances
Ageing Population
Scientific Advances
Increased antifungal resistance
Dimorphism
Changing of shape.
e.g Yeast to hyphae
Polymorphic
Many different forms
What sort of infection do Opportunistic Fungi cause?
Secondary
What sort of individuals do Primary Fungi infect?
Healthy
What are primary fungi catergorised as?
CAT3
Examples of CAT3 Fungi
Blastomyces dermatitidis
Histoplasma Capsulatum
Coccidioides Immitis
Cryptococcus Gattii
What is an example of a fungi that causes solely a superficial infection?
Malassezia Furfur
What is an example of a fungi that causes superficial, subcutaneous and Systemic infections?
Candida Albicans
What is an example of a fungi that causes solely systemic infections?
Mucormycetes
Virulence
Intensity of Pathogenicity, the more virulence = the faster it will kill you.
Virulence factor
A factor that functions to increase virulence
Virulence
The intensity of Pathogenicity, the more virulence = the faster it will kill you.
Fitness Attributes
Function is required for growth. Gene required for growth of the pathogen.
What happens if you knock out a virulence gene?
Virulence decreases and deaths caused by the virus decrease also.
What is the difference between fitness attributes and virulence factors?
Virulence factors affect pathogenicity, and fitness attributes are essential for the growth of the pathogen.
What causes Seborrhoeic Dermatitis?
Malassezia Furfur
What is Malassezia Furfur dependent on for growth?
Exogenous lipids use natural oils and sebum.
Metabolises sebum into fatty acids.
How does Malassezia Furfur use fatty acids?
Saturated is used for metabolism.
Doesn’t use unsaturated.
What happens to the unused unsaturated fat?
Accumulates on the skin and irritates it which leads to itching and flaking of the skin.
What is ringworm caused by?
Trichophyton Mentagrophytes
How is ringworm transmitted?
It is dependent on human and animal infection for survival and dissemination of species.
What does candida Albicans cause?
Skin infections, genital and oral thrush as well as systemic disease
Where are candida Albicans infections primarily acquired?
Hospitals
- Biofilms in catheters / infected lines
What is aspergillosis known as?
Farmers lung
How do you acquire farmers lung?
Fungi grows in hay/fields, spores are then inhaled and a fungal ball forms in the lungs.
This damages the lungs and respiratory epithelium.
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