Session 2 - Multicausality of Diseases Flashcards
Define Health
A state of complete physical, mental and social well-being and not merely the absence of disease or infirmity.
Define communicable disease.
It is caused by microorganisms and can be spread directly or indirectly from one person to another. Some are transmitted through vectors.
What is causation?
An event, condition, characteristic or a combination of these factors, which plays an important part in the development of disease.
What is a necessary cause?
A factor that must be present for a disease to occur
Explain direct causal associations.
This is where a causal factor leads straight to the outcome and there are no other factors intervening.
What is Dose?
The number of infectious agents needed to cause disease
What is virulence?
the ability to infect
What is pathogenicity?
the ability to cause disease
What is survival?
the ability to survive outside the host
What are causative agents not limited to?
Biological agents
What can causative agents include aside from biological agents?
Chemical agents and Physical agents
List 5 examples of biological agents.
- bacteria
- virus
- parasites
- protozoan
- fungus
List 4 examples of chemical agents.
- pesticides
- food additives
- pharmacologic
- industrial chemicals
List 6 examples of physical agents
- heat
- light
- radiation
- noise
- vibration
- speeding objects
Name the 4 types of host factors
- predisposing factors
- enabling factors
- precipitating factors
- reinforcing factors
What are predisposing factors?
factors that make the body more susceptible to disease
What are modulating factors?
factors that assist in the development of the disease
What are precipitating factors?
factors which are associated with immediate exposure to the disease agent.
What are reinforcing factors?
factors that aggravate an already existing disease
List 5 examples of predisposing factors.
- Gender
- Race
- Genes
- Ethnicity
- Blood group
List 8 examples of modulating factors.
- age
- marital status
- lifestyle
- medication
- nutrition
- immunity
- previous diseases
- socio-economic status
What does macro-environment entail?
- recreational
- transport
- residential
- work
What does micro-environment entail?
- biological
- psychological
- physical/chemical
Name the 5 determinants of health.
- biological
- cultural and behavioural
- environmental
- economic and political
- social
What are determinants of health?
A range of personal, social, economic and environmental factors that influence health status.
What does the epidemiological triad causality model entail?
It states that disease depends on the critical balance between environment, agent and host.
Define host.
Refers to the human who can get the disease
What does ‘environment’ entail in the epidemiological triad? List 6 points.
- climate
- living conditions
- work conditions
- access to healthcare
- air quality
- sanitation
What is a causal pathway?
A pathway where one factor leads to another until eventually the specific pathogenic agent becomes present in the organ that gets damaged.
List 4 examples of biological determinants of health.
- infective agent
- protozoa
- genetics
- gender
List 4 examples of cultural & behavioural determinants of health.
- gender culture
- gender-based violence
- xenophobia
- high risk behaviours
List 5 examples of environmental determinants of health.
- Rural vs urban
- air pollution
- water
- soil
5.climate change
List 3 examples of economic & political determinants of health.
- war
- political tensions
- poor economy
What are social determinants of health?
the conditions in which people are born, grow, live, work and age
List 7 examples of social determinants of health.
- agriculture and food production
- education
- work environment
- unemployment
- water and sanitation
- healthcare services
- housing
Name the 6 components of the infectious disease process.
- causative agent
- reservoir for the agent
- portal of exit of the agent from the host
- mode of transmission of the agent to a new host
- portal of entry into the new host
- host susceptibility
Explain the causation of disease using Koch’s postulate.
- agent must be present in every case of the disease
- agent must be able to be isolated and grown in pure culture
- once isolated, agent must be capable of reproducing disease in susceptible animal
- agent must be re-isolated from new host and shown to be the same as the originally inoculated agent
Explain the causation of disease using the web of causation model.
Several causes or contributing factors together give rise to disease and each of these factors is also influenced by a variety of other factors which can be known or unknown. These factors can activate the disease directly or indirectly.
What is the cause of ischemic heart disease?
- genetics
- hypertension
- obesity
What are the causes of HIV?
- unprotected sex with an infected person
- sharing needles
- transmission from mother to foetus during birth when blood mix
What are the causes of lung cancer?
- smoking
- exposure to asbestos
- exposure to radon gas
- genetics
What are the causes of diabetes?
- immune system destroying cells making insulin
- genetics
- being overweight
- lack of exercise
What are the causes of diarrhea?
- alcohol abuse
- bacterial infection
- allergies to certain foods
What are the causes of respiratory illness?
- influenza A or B
- respiratory syncytial virus
- adenovirus
What is an indirect cause?
A causal factor that indirectly causes a certain outcome by means of intervening factors
