Epidemiology Lecture Notes PDF

EPIDEMIOLOGY EPI 2004 LECTURER: MRS. BECKFORD HARVEY PHN, MPH, THM, ( PHD CANDIDATE) OBJECTIVES AT THE END OF THE UNIT, THE STUDENT SHOULD: DEFINE THE TERMS EPIDEMIOLOGY AND THE EPIDEMIOLOGIC APPROACH. DISCUSS THE AIMS, USES AND VARIABLES IN EPIDEMIOLOGY. ...

EPIDEMIOLOGY EPI 2004 LECTURER: MRS. BECKFORD HARVEY PHN, MPH, THM, ( PHD CANDIDATE) OBJECTIVES AT THE END OF THE UNIT, THE STUDENT SHOULD: DEFINE THE TERMS EPIDEMIOLOGY AND THE EPIDEMIOLOGIC APPROACH. DISCUSS THE AIMS, USES AND VARIABLES IN EPIDEMIOLOGY.  HISTORICAL FIGURES AND EVENTS FATHER OF EPIDEMIOLOGY -JOHN SNOW CONDUCTED PIONEERING INVESTIGATIONS ON CHOLERA EPIDEMICS IN ENGLAND AND PARTICULARLY IN LONDON IN 1854 IN WHICH HE DEMONSTRATED THAT CONTAMINATED WATER WAS THE KEY SOURCE OF THE EPIDEMICS. EDWARD JENNER FOUND IN 1798 THAT SMALLPOX COULD BE PREVENTED BY INOCULATION WITH SUBSTANCE FROM COWPOX LESIONS- 1ST DOCUMENTED CASE OF PREVENTING DISEASE THROUGH VACCINATION  HISTORICAL FIGURES AND EVENTS JAKOB HENLE, LOUIS PASTEUR AND ROBERT KOCH ARE KEY FIGURES CREDITED WITH DEVELOPING THE GERM THEORY OF DISEASE. THE THEORY WAS 1ST EXPLAINED IN 1840 JOHN GRAUNT FURTHER ADVANCED THE USE OF VITAL STATISTICS IN 17TH CENTURY ( TALLYING OF POPULATION –BASED VITAL STATISTICS DATES BACK TO THE BUBONIC PLAGUE THAT KILLED ¼ OF EUROPE’S POPULATION BETWEEN 1346 AND 1352 USE OF LIFE TABLES TO SUMMARIZE MORTALITY EXPERIENCE NOTING URBAN-RURAL DIFFERENCES, HIGH MORTALITY RATES IN CHILDREN AND DIFFERENCES IN MORTALITY AND MORBIDITY IN MEN AND WOMEN  HISTORICAL FIGURES AND EVENTS PETER LUDWIG PANUM IN 1846 STUDIED THE VIOLENT OUTBREAK OF MEASLES USED INFECTIOUS DISEASE PRINCIPLES TO DETERMINE HOST SUSCEPTIBILITY AND AGENT INFECTIVITY CALCULATED THE INCUBATION PERIOD FOR MEASLES CONCEPTS OF EPIDEMIOLOGY UNIT 1 DEFINE THE TERM EPIDEMIOLOGY EPI-: DERIVED FROM THE GREEK WORD "EPI," MEANING "UPON" OR "AMONG." IT INDICATES SOMETHING THAT IS RELATED TO A POPULATION OR A COMMUNITY.- DEMOS-: COMES FROM THE GREEK WORD "DEMOS," MEANING "PEOPLE" OR "POPULATION." THIS PART OF THE TERM FOCUSES ON THE PEOPLE OR POPULATION GROUPS BEING STUDIED. -LOGY: FROM THE GREEK "LOGOS," MEANING "STUDY" OR "SCIENCE." THIS SUFFIX INDICATES THAT EPIDEMIOLOGY IS A FIELD OF STUDY OR A BRANCH OF SCIENCE. THE STUDY OF SOMETHING THAT AFFLICTS/AFFECTS A POPULATION. EPIDEMIOLOGY IS THE STUDY OF FACTORS THAT DETERMINE THE OCCURRENCE AND DISTRIBUTION OF DISEASE IN HUMAN POPULATIONS. DEFINE THE TERM EPIDEMIOLOGY CONT’D EPIDEMIOLOGY IS CONCERNED WITH THE DISTRIBUTION AND DETERMINANTS OF HEALTH AND DISEASE, MORBIDITY, INJURIES, DISABILITY, AND MORTALITY IN POPULATIONS. ( FRIIS & SELLERS 2009) A WIDELY ACCEPTED FEATURE OF EPIDEMIOLOGY IS THAT IT EXAMINES DISEASE OCCURRENCE AMONG POPULATIONS RATHER THAT AMONG INDIVIDUALS. HENCE, EPIDEMIOLOGY IS OFTEN REFERED TO AS “ POPULATION MEDICINE” THE EPIDEMIOLOGIC AND CLINICAL DESCRIPTION OF A DISEASE ARE QUITE DIFFERENT CLINICAL DESCRIPTION WOULD LIST SPECIFIC SIGNS AND SYMPTOMS- (MI) CHEST PAIN, HEART RATE, NAUSEA, ETC EPIDEMIOLOGIC DESCRIPTION WOULD INDICATE WHICH AGE GROUP WOULD MOST LIKELY BE AFFECTED , SEASONAL TRENDS IN HEART ATTACK RATES, GEOGRAPHIC VARIATIONS IN FREQUENCY ETC  DEFINE THE TERM EPIDEMIOLOGIC APPROACH. THE EPIDEMIOLOGIC APPROACH REFERS TO THE METHOD USED IN PUBLIC HEALTH AND MEDICINE TO INVESTIGATE, UNDERSTAND, AND MANAGE HEALTH-RELATED EVENTS, DISEASES, AND CONDITIONS WITHIN POPULATIONS. DISCUSS THE AIMS, USES AND VARIABLES IN EPIDEMIOLOGY. AIMS- TO DESCRIBE, TO EXPLAIN ,TO PREDICT AND TO CONTROL. DESCRIBE- THE HEALTH STATUS OF POPULATIONS EXPLAIN -THE ETIOLOGY OF DISEASE PREDICT -THE OCCURRENCE OF DISEASE CONTROL THE DISTRIBUTION OF DISEASE  DISCUSS THE AIMS, USES AND VARIABLES IN EPIDEMIOLOGY CONT’D USES TO STUDY THE HISTORY OF THE HEALTH OF POPULATIONS PUBLIC HEALTH SURVEILLANCE: CONTINUOUS MONITORING OF DISEASE OCCURRENCE TO DETECT AND CONTROL OUTBREAKS, IDENTIFY HEALTH TRENDS, AND GUIDE PUBLIC HEALTH INTERVENTIONS. DISCUSS THE AIMS, USES AND VARIABLES IN EPIDEMIOLOGY CONT’D USES CONT’D TO DIAGNOSE THE HEALTH OF THE COMMUNITY COMMUNITY DIAGNOSIS INVOLVES IDENTIFYING THE HEALTH PROBLEMS AND RISK FACTORS PREVALENT IN A COMMUNITY TO PRIORITIZE AND ADDRESS PUBLIC HEALTH NEEDS. TO STUDY THE WORKING OF HEALTH SERVICES DISCUSS THE AIMS, USES AND VARIABLES IN EPIDEMIOLOGY CONT’D USES CONT’D TO IDENTIFY SYNDROMES TO COMPLETE THE CLINICAL PICTURE TO SEARCH FOR CAUSES OF HEALTH AND DISEASE TO ESTIMATE FROM THE GROUP EXPERIENCE WHAT ARE INDIVIDUAL RISK ON AVERAGE OF DISEASE, ACCIDENT, AND DEFECTS , AND THE CHANCES OF AVOIDING THEM