Investigation Of An Outbreak In A School

INVESTIGATION OF AN OUTBREAK IN A SCHOOL

OBJECTIVES OF AN EPIDEMIC INVESTIGATION TO DEFINE THE MAGNITUDE OF THE EPIDEMIC OUTBREAK TO DETERMINE THE FACTORS RESPONSIBLE TO IDENTIFY CAUSE,SOURCE OF INFECTION,MODES OF TRANSMISSION,CONTROL MEASURES

INVESTIGATION IS MAINLY RETROSPECTIVE

STEPS 1.

VERIFICATION OF DIAGNOSIS: CLINICAL EXAMINATION OF CHILDREN

2.

CONFIRMATION OF THE EXISTENCE OF AN EPIDEMIC: BY COMPARING DISEASE FREQUENCIES DURING SAME PERIOD OF PREVIOUS YEARS

STEPS 3. DEFINING THE POPULATION AT RISK: COUNTING THE NO. OF CHILDREN IN THE SCHOOL

4. RAPID SEARCH FOR ALL CASES & THEIR CHARACTERISTICS: *MEDICAL SURVEY- SCREENING EACH CHILD IN SCHOOL *EPIDEMIOLOGICAL CASE SHEET- EG. FOOD H/0 *SEARCHING FOR MORE CASES-UPTO TWICE INCUBATION PERIOD OF DISEASE

STEPS 5. DATA ANALYSIS: *TIME - COLLECT DATES OF ONSET & CONSTRUCT EPIDEMIC CURVE *PLACE – PREPARE A SPOT MAP & RELATION TO POSSIBLE SOURCES OF INFECTION *PERSON – eg. FOOD BORNE OUTBREAKS-FOOD SPECIFIC ATTACK RATES CALCULATED FOR EACH FOOD EATEN TO DETERMINE SOURCE OF INFECTION

6. FORMULATION OF HYPOTHESES SOURCE CAUSATIVE AGENT POSSIBLE MODE OF SPREAD ENVIRONMENTAL FACTORS

STEPS 7. TESTING OF HYPOTHESES: BY COMPARING ATTACK RATES IN VARIOUV GROUPS OF THOSE EXPOSED & NOT EXPOSED TO EACH SUSPECTED FACTOR

8. EVALUATION OF ECOLOGICAL FACTORS: SANITARY STATUS, WATER, MILK SUPPLY,

9. FURTHER INV. OF POPULATION AT RISK:

10.WRITING THE REPORT BACKGROUND HISTORICAL DATA METHODOLOGY OF INVGS. ANALYSIS OF DATA CONTROL MEASURES