6 - epidemiology Flashcards
Define epidemiology
The study of factors, implicated in disease progression, that determine its frequency distribution severity and cohorts of individuals
What are the three causal factors needed for disease
An external agent (such as a virus or poison)
a susceptible host
environmental that brings the agent and host together
What is an endemic disease?
A disease that occurs at a constant rate within a given population
What is an epidemic?
an outbreak that occurs when there is an increased incidence of a disease beyond that which is normally found in the population (the endemic rate)
Give two examples of how ethnic background impacts disease susceptibility
- people of African or Mediterranean heritage are more likely to have sickle cell anemia
- Tay-Sachs disease is more common in people of Ashkenazi Jewish or French Canadian ancestry
What percentage of deaths are caused by cancer?
Approximately 13%
What types of cells are more likely to develop cancer?
Those that divide more rapidly (like blood cells and skin cells)
What are some risk factors for cancer?
Age, tobacco, poor diet and physical inactivity
What are some other carcinogens?
Asbestos, benzene, viruses (such as HPV and RSV), aflatoxin B and radiation
Give some examples of cancers that can be caused by carcinogens
Lung, colon, breast, stomach, bladder, prostate and pancreas
What types of diseases are causing the most deaths now?
Chronic disease
What is the epidemiological transition?
A shift in the main cause of death from infectious diseases to non-infectious diseases
Describe the epidemiology of influenza A
- fatality rate usually less that 0.1%
- multiple epidemics and 4 pandemics
- caused by antigenic shift and drift
