Determinants and Causation - Part 1 Flashcards
What is disease ecology paradigm?
The incidence, spatial distribution and timing of diseases refelect the interactions of populations with each other, in the environment
What is a disease determinant?
Any factor or variable that can affect the frequency of disease occurence in a population
Difference between primary and secondary disease determinant?
Primary: necessary for disease to occur, such as the pathogen itself
Secondary: not necessary but can influence the process, compromized immune system
Four Host determinants?
Genotype
Breed/Subspecies
Age
Sex
Example of host determinant - genotyp
Hereditary Equine Regional Dermal Asthenia
- Autosomal recessive trait in Quarter Horses
- G to A substitution in the sequence of cyclophilin B
Example of host determinant - breed, subspecies
The N’Dama Cattle is tolerant to trypanosoma congolese while the Zebu is sensitive
What is the W shaped curve?
Shows the susceptibilty of people to the flu 1918 flu epidemic based upon age, you midleage and old affected
2 examples of host determinant - sex
Canine Hemophilia - sex-linked genetic disease
Schistosoma mansoni infections are more common and more intesne in male baboons than female baboons
How can sex play a role in host determinant?
Sex -linked diseases
Behaviour, ie, the male baboons are frequent the water more than females and therefore are more susceptible to the pathogen which resides in the body of water
2 Agent determinants
Genetic differences between strains
Gene content and virulence factors
3 general things that affect disease potential?
Agent
Host
Environment
What are some examples of host variables that can change disease potential?
Species
Age
Sex
Breed
Genotyp
What are some things with in environment that can affect disease potential
Weather
Housing
Geography
Management
Food
What are some parts of agent that can affect disease potential
Infectivity
Pathogenicity
Immunogenicity
Atigenic stability
