On 29th September 2004,48 people enjoyed a feast in a
village in Udupi district.
The feast was a lunch served at 13:00 hrs.
At varying times subsequently,24 of the 48 people
developed G.I.symtoms which required treatment.
7 of the cases were reported on 29th
13 on the 30th and 4 on the 1st of October.
47 out of 48 villagers who attended the feast were traced.
If you were the part of out break investigation team
What will you do at this point?
List the steps in order of priority
►A plan for conducting an outbreak investigation
will be designed
► Itwill be conducted according to the following
Clinical cases + surv+
Comm.representatives Information regarding possible epidemic
Records & seasonal
Establish presence of epidemic incidence
component Confirm diagnosis Isolate & treat cases component
Conduct case finding Attack source & transmission
Trace contact prevention
Conduct environmental Continue
Process & analyse data
Health plans for prevention of recurrence
b.Construct a proforma / questionnaire with
which you can collect data .
C. Comment on the response rate of the survey.
Why is it important?
► Response rate = It is the percentage of total
number of people traced divided by the total no
of people exposed.
► Response rate = 47/48 x 100 = 97.91%
► Goodresponse rate ensures better description
of the magnitude and geographic extent of the
d. Construct an epidemic curve using the relevant data
comment on the shape of the curve and the type of
29th 30th 1st
► Thecurve rises and falls steep with peak
during the second day.
► Theepidemic curve shows it’s a point
► Because all the cases occur within one
incubation period of the disease