Epidemiology - study of factors that determine the occurence and distribution of disease in a population
Epi - upon
Demos - population
Logos - study
Epidemiologists - deal with data from group of patients or even entire population
Classical Epidemiology
studies the distribution and determinants of disease in populations and the community origina of health problems
interested in discoveringrisk factor that might be altered in a population to prevent or delay disease, injury, and death
Clinical Epidemiology
application of principles of epidemiology to clinicalmedicine
clinical epidemiologists often study patients in health-caresettings rather than in the community at large
Etiology - cause or origin of a disease or abnormal condition
NaturalHistory - way a diseaseprogresses in the absence of medical or public health intervention
Predisease - before the disease process begins
Primary Prevention - preventing the disease process from starting
Latent - disease process has already begun but is still asymptomatic
Secondary Prevention - screening for the disease and providing appropriate treatment that may preventprogression to symptomatic disease
Symptomatic - disease manifestations are evident
Tertiary Prevention - disease manifestations are evident intervention may slow, arrest, or reverse the progression of disease
Agent
what of the triangle
whatever causes the disease
four categories ;
biologic agents
chemical agents
physical agents
social and psychologic stressors
Host
who of the triangle
the person or organism harboring the disease
resistance is influenced by; genotype,nutritionalstatus, bodymassindex,immune system and behaviour
Environment
where of the triangle
external factors that causes or allow disease transmission
Vectors
how of the triangle
serves as vehicles to transmit disease
include insects,arachnids, and mammals
to be an effective transmitter of disease, the vector must have a specific relationship to the agent, the environment, and the host
BEINGs Model - serve as mnemonic device for the major categories of risk factors for disease
Biologic factors and Behavioral factors
Environmental factors
Immunologic factors
Nutritional factors
Genetic factors
Services, Social factors, and Spiritual factors
Vaccination
herd immunity/population immunity - protects the immunized individual, but also prevents that person from transmitting the disease to others
indirect protection - from an infectious disease that happens when a population is immune either through vaccination or immunity developed through previous infection
Solution of Public Health Problems
vaccination
improved sanitation
vector control
erection of large river dams
Epidemiological Principles and methods are applied in
clinicalresearch
diseaseprevention
health promotion
health protection
health servicesresearch
ultimate aim of epidemiology aims and objectives of epidemiology
to eliminate or reduce the health problems of community
to promote the health and well-being of society as a whole
Distribution
time,place,person
pattern - hypothesis for causative/risk factor = etiologicalhypothesis
descriptive epidemiology
Determinants
causes, risk factors,mode of transmission
how and why of disease
identifying the causes and risk factors for diseases
testing the hypothesis - biostatistics
analytical epidemiology
Scope of Epidemiology
causation of the disease
natural history of the disease
health status of the population
evaluation of interventions
Applications of Epidemiology in Public Health
preventing the diseasw and promotinghealth
community health assessment (community diagnosis) and prioritysetting
improving diagnosis,treatment, and prognosis of clinical diseases
evaluating health interventions and programs
PublicHealth - refers to collective actions to improvepopulation health
Epidemiology - one of the tools for improving publichealth, is used in several ways
Epidemiology
unit of study - definedpopulation or population at risk
concerned with the disease pattern in entirepopulation
concerned with both sick and healthy
Clinical Medicine
unit of study - case
physician is concerned with the disease in the individualpatient
Epidemiology
epidemiologist is confronted with the relevant data derived from the particularepidemiologicalstudy (communitydiagnosis)
seek to identify the source of infection, mode of transmission, and an etiological factor to determine the future trends, prevention, and control measure
Clinical Medicine
physician seeks to diagnosis for which he derives prognosis and prescribes specifictreatment
Epidemiology
epidemiologists goes to the community to find out the diseasepattern and suspected causalfactors in the question
Clinical Medicine
patient comes to the doctor
Epidemiological Approach
asking questions
making comparisons
5 W’s
case definition - what
person - who
place - where
time - when
causes - why
Making Comparisons
find out the differences in the agents, host, and environment conditions between two groups
weighs, balances, and contrasts give clues to etiological hypothesis