Intro To Epidemiology Flashcards
What is epidemiology
Study of distribution and determinants of health related events in specific population and application of the study to control health outbreaks
-study of How disease are distributed and what factors influence the distribution and how the factors influence the distribution
Characteristics of epidemiology and describe frequency and pattern
- it’s is a science discipline
- branch of public health
- looks at frequency and pattern of health events in a population
- seeks to identify and evaluate causes and factors that influence health related events (determinants)
- Frequency is how often or how much does this happen
- pattern is when does this occur how does the disease spread and who is more affected
Fundamental assumptions
- Human disease does not occur at random in population he’s always a reason to the cause (determinants)
-These determinants which drive disease can be identified by systematic research two types of factors
1 risk increases risk of getting disease
2protective prevents chances of contracting diseases
- Modifying or influencing these factors it is possible to change disease occurrence
Evolution
1 Hippocrates ( 500 BC ) -In an easy “on air water and places “he described how occurrence of disease was influenced by a number of things
2 John Graunt ( 1662 )
- Recognized the value of routinely collected data
- quantified birth, death and disease using data collected by doctors
- noticed disparities in male-female ,seasonal variations and High infant mortality
3 William Farr ( 1807-1883 )
- Carried out more detail of analysis of collected data
- described of disease occurs in a population dynamics of epidemiology
4 John Snow ( Cholera outbreak 1853-54 London )
- Father of modern epidemiology
- His work illustrated the sequence from descriptive to hypothesis generation too hypothesis testing and to application
5 Ignaz Semmelems and child bed fever
- observed higher rates of sepsis in physician and student ward staff compared to midwife staff wards
- led to policy formation that is handwashing
6 Edward Jenner
- Father of modern immunology
- observed dairy maids to be unaffected by small box
- developed first vaccine cowpox inoculate small box
Cholera Outbreak in London and John Snow efforts
- Firstly he determined where people with cholera lived and worked
- Mapped the distribution of cases
- Noticed that areas with water supplied by Southwark and Vauxhall had eight Ford cases of cholera compared to Lambert areas
- Postulate that cholera is transmitted by contaminated water
- suggested to change what collection point to the companies
What is peupera sepsis
And infection when a woman gives birth and the reproductive tract is invaded bacteria
Pioneers of modern epidemiology
- Doll and Holl : Case control design to link smoking and lung cancer
- Cohort Design : Framingham heart study to link smoking by physicians to heart disease
- Clinical trials : in 1950 USA Treated a group of kids with a vaccine and gave placebos to others (used to evaluate treatment implementations)
5 Main aims of epidemiology
1 identify cause of disease ( etiology )
2 determine burden of disease found in population
3 study natural history and prognosis of disease
4 produce knowledge for prevention and care of disease
5 produce foundation for developing public health policy
Factors which change global health patterns
- urbanization
- aging
- medical developments
- changing lifestyle
- globalization
Two main branches of epidemiology
1 descriptive - characterize quantity ( how many people )in distribution ( were is it spread and at what times and who has it )of a disease in terms of a place at persons ( who is infected )in a population
2 analytical - Try to explain disparities in distribution between subgroups what are the drivers of the disease factors affecting the spread of the disease
Variation of disease can be real or an illusion due to
- chance
- observational error
- health care seeking behavior
- changes in clinical approach to diagnosis
- changes in data collection system
- change in underlying population
Causes of disease variation
Epidemiology triad - if one is affected then variation changes
- agent
- host
- environment
