Transcript Getting to the essential

What have we learned in the last
two weeks
Key take home messages from the Integrated Disease
Surveillance Programme (IDSP) district surveillance
officers (DSO) course
Surveillance:
A role of the public health system
The systematic process of collection,
transmission, analysis and feedback of public
health data for decision making
Data
Information
Analysis
Action
Interpretation
Surveillance
A dynamic vision of surveillance
Collect and
transmit
Make
decisions
data
All levels use
information
to make
decisions
Feedback
information
Analyze
data
The private sector can treat patients but
only the public sector can coordinate surveillance
Surveillance
Type of data: Summary
Qualitative
Quantitative
Binary
Nominal
Ordinal
Discrete Continuous
Sex
M
M
F
M
F
F
M
M
F
M
F
F
M
M
M
F
M
F
M
Nationality
Yemen
Jordan
Yemen
Jordan
Sudan
Yemen
Sudan
Iran
Jordan
Iran
Yemen
Sudan
Iran
Yemen
Jordan
Jordan
Iran
Sudan
Yemen
Status
Mild
Moderate
Severe
Mild
Moderate
Mild
Moderate
Severe
Severe
Mild
Moderate
Moderate
Mild
Severe
Severe
Moderate
Mild
Mild
Mild
Children
1
1
2
3
1
1
2
3
2
2
1
1
1
2
2
3
2
3
1
Weight
56.4
47.8
59.9
13.1
25.7
23.0
30.0
13.7
15.4
52.5
26.6
38.2
59.0
57.9
19.6
31.7
15.1
33.9
45.6
Quick definitions of
measures of central tendency
• Mode
 The most frequently occuring observation
• Median
 The mid-point of a set of ordered observations
• Arithmetic mean
 Aggregate / sum of the given observations
divided by the number of observation
Prevalence – (P)
• Number of existing cases (old and new) in a
defined population at a specified point of
time
Number pf people with disease at a specified time
P = ---------------------------------------------------- x 10n
Population at risk at the specified time
• In some studies the total population is used
as an approximation if data on population at
risk is not available
Prevalence
Incidence – (I)
• Number of new cases in a given period in a
specified population
 Time, (i.e., day, month, year) must be specified
• Measures the rapidity with which new cases
are occurring in a population
• Not influenced by the duration of the disease
Incidence
Reporting units for disease surveillance
Public sector
(Exhaustive)
Private
(Sentinel)
Rural
•Sub-centres (SCs)
•Primary health centres
(PHCs) and block PHCs
•Community health
centres (CHCs)
•Sub-district/district
hospitals
•Indian medicine units
•Practitioners
•Hospitals
Urban
•Dispensaries
•Urban hospitals
•Public health labs
•ESI/Railways/Defence
facilities
•Medical colleges
•Nursing homes
•Hospitals
•Medical colleges
•Laboratories
Reporting units
Types of case definitions in use
Case definition Criteria
Users
Syndromic
(suspect)
Clinical pattern
Paramedical personnel and
members of community
Presumptive
(Probable)
Typical history and
clinical examination
Medical officers of primary
and community health
centres
Confirmed
Clinical diagnosis by a Medical officer and
medical officer and
Laboratory staff
positive laboratory
identification
Case definitions
Information flow of the weekly
surveillance system
Sub-centres
Programme
officers
S.S.U.
P.H.C.s
C.H.C.s
Dist. hosp.
D.S.U.
Pvt. practitioners
Nursing homes
Private hospitals
Med. col.
P.H. lab.
C.S.U.
Private labs.
Other Hospitals:
ESI, Municipal
Rly., Army etc.
Corporate
hospitals
District surveillance committee
CMO
(Co. Chair)
Representative
Water Board
District Program Manager
Polio, Malaria, TB, HIV - AIDS
Superintendent
Of Police
Chief District PH
Laboratory
IMA
Representative
District Data Manager
(IDSP)
Chairperson*
District surveillance committee
NGO
Representative
Representative
Pollution Board
Superintendent
of hospitals
District Training Officer
(IDSP)
District Panchayat
Chairperson
* District collector or
district magistrate
District Surveillance Officer
(Member Secretary)
Medical College
Representative
if any
Case
Feedback
Reporting unit
Immediately
Lab slip
Outpatient
register
Inpatient
slip
Weekly
Lab register
+ve slides +
sample -ves
Form L
Common
reporting
form P
Weekly
Inpatient
register
Weekly
District
public
health
laboratory
Computer
(District)
District
surveillance
officer
Functions of the district surveillance unit
• Managerial
 Implement and monitor all project activities
 Coordinate with laboratories, medical colleges, non governmental
organizations and private sector
 Organize training and communication activities
 Organize district surveillance committee meetings
• Data handling
 Centralize data
 Analyze data
 Send regular feedback
• Outbreak response
 Constitute rapid response teams
 Investigate
Distribution of cases by sex
REC SEX
--- ---1 M
2 M
3 M
4 F
Data
5 M
6 F
7 F
8 M
9 M
10 M
11 F
12 M
13 M
14 M
Information
15 F
16 F
17 F
18 M
19 M
20 M
21 F
22 M
23 M
Data analysis is
24 F
25 M about data reduction
26 M
27 M
28 F
29 M
30 M
Table
Sex
Frequency
Proportion
Female
10
33.3%
Male
20
66.7%
Total
30
100.0%
Graph
Female
Male
Why analyze?
1. Count, Divide and Compare (CDC): An
epidemiologist calculates rates and
compare them
• Direct comparisons of absolute numbers of cases are
not possible in the absence of rates
• CDC
 Count
• Count (compile) cases that meet the case definition
 Divide
• Divide cases by the corresponding population denominator
 Compare
• Compare rates across age groups, districts etc.
CDC for TPP
2. Time, place and person
descriptive analysis
A. Time

Incidence over time
B. Place

Map
C. Person

Breakdown by age, sex or personal
characteristics
CDC for TPP
0
2000
2001
2002
2003
May
June
July
August
September
October
November
December
30
February
March
April
May
June
July
August
September
October
November
December
January
February
March
April
May
June
July
August
September
October
November
December
January
February
March
April
35
January
February
March
April
May
June
July
August
September
October
November
December
January
February
March
April
May
June
July
August
September
October
November
December
January
Incidence of malaria per 10,000
TIME: Incidence graph
Malaria in Kurseong block, Darjeeling
District, West Bengal, India, 2000-2004
45
40
Incidence of malaria
Incidence of Pf malaria
25
20
15
10
5
2004
Months
Interpretation: There is a seasonality in the end of the year and a
trend towards increasing incidence year after year
Reports
PLACE: Map
Incidence of acute hepatitis (E) by block,
Hyderabad, AP, India, March-June 2005
Attack rate per
100,000
population
0
1-19
20-49
50-99
100+
Open drain
Pipeline crossing
open sewage drain
Interpretation: Blocks with hepatitis
are those supplied by pipelines
crossing open sewage drains
PERSON: Incidence by age and sex
Probable cases of cholera by age and
sex, Parbatia, Orissa, India, 2003
Age group
(In years)
Sex
Tot al
0 to4
5 to14
15 to24
25 to34
35 to44
45 to54
55 to64
> 65
Male
Female
Total
Number of cases Population Incidence
6
113
5.3%
4
190
2.1%
5
128
3.9%
5
144
3.5%
6
129
4.7%
4
88
4.5%
8
67
11.9%
3
87
3.4%
17
481
3.5%
24
465
5.2%
41
946
4.3%
Interpretation: Older adults and women are
at increased risk of cholera
CDC for TPP
Components of early warning surveillance
Surveillance:
Case-based surveillance
Event-based surveillance
Data
Reports
Analyze
Filter
Signal
Signal
Validate
Verify
Alert
Response
Assess
Public health alert
Investigate
Control measures
Post-outbreak
strengthening
Evaluate
Early warning
Progressive response
• Levels of alert are progressively increasing
• Unusual signals require filtering / validation
• The best chance of detection is to:
 Analyze regularly
 Be familiar with the time, place and person
characteristics of the diseases in your area
Triggers
Objectives of an outbreak investigation
Host
1. Verify
2. Recognize the
magnitude
3. Diagnose the agent
4. Identify the source
and mode of
Environment
Agent
transmission
An outbreak comes from a change
5. Formulate prevention in the way the host, the environment
and control measures
and the agent interact:
This interaction needs to be understood
to propose recommendations
Investigations
Working well with the laboratory
• Develop rapport with the laboratory
• Collect specimen according to the guidelines
and access on-line resources if needed
• Protect the patient, yourself and others with
biosafety
• You can contribute to quality assurance!
Investigating an outbreak
Unusual event:
Is this an outbreak?
Yes
-> Are the source and
modes of transmission
known?
Yes
-> Control measures
No
No
-> Clinical, microbiological
and epidemiological investigation
Time, place person description
Formulation of hypothesis
Hypothesis fit the facts:
-> Control measures
Hypothesis does not fit the facts:
-> Analytical investigations
Steps of a full outbreak investigation
using analytical epidemiology to identify
the source of infection
1.
2.
3.
4.
5.
Determine the existence of an outbreak
Confirm the diagnosis
Define a case
Search for cases
Generate hypotheses using descriptive findings
•
6.
Test hypotheses based upon an analytical study

7.
8.
9.
10.
Time, place and person information
Compare cases with non cases
Draw conclusions
Compare the hypothesis with established facts
Communicate findings
Execute prevention measures
Maximizing the chances that results of an
investigation is used for action
• Appreciate the point of view of the manager
 Don’t flag problems
 Provide solutions
• Understand that your recommendations have implications for
resources allocation
• Deliver useful recommendations






Evidence based
Specific
Feasible
Cost effective
Acceptable
Ethical
Decision makers
Communicating results effectively
•
•
•
•
Communicate WITH and not TO the audience
Keep in mind what is needed out of people
Pilot test communication material
Have your oral presentations guided by a
clear SOCO
The six “S” of technical writing
1.
2.
3.
4.
5.
6.
Simple
Short
Structured
Sequential
Strong
Specific
The six “S”
Using high-level outlines to
prepare a report
• Skeleton of the report in bullet points
• Outline of various sections
 Spell out all titles
 Use outline format of word processors
 Summarize each paragraph with a bullet point
• List of tables and figures
 Spell out titles
• Reach consensus on the outline
• Expand
The six “S”
Always add summary to your reports
• The audience of your report may be too busy
to read it completely
• Summary:
 < one page
 < 300 words
• Structure your summary with subheadings
"I'm sorry to write you a long letter.
I had no time to write a shorter one”
Mark Twain
The six “S”
Rationale for feedback
of surveillance data
 Motivation
• Those who collected data see how they fit in the bigger
picture
 Reliability
• Identifies errors
 Reactivity
• Places everyone on the same page
 Quality
• Increases transparency
 Education
• Demonstrates how the system works
Data flow and feedback: Level by level
Centre
State
Data
District
Primary / Community
health centre
Community
Feedback
Content of feedback
• Information on diseases under surveillance
 Summary data tables
 Analyzed epidemiological information
• Time (Graphs with trends)
• Place (Maps)
• Persons (Tables)
• Information on quality of data collected
Content of feedback
• Information on diseases under surveillance
• Information on quality of data collected
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
Regularity of reporting
Timeliness of reporting
Completeness of reporting
Responses initiated by the unit
Validity of data
Integrated disease surveillance
programme activities to be monitored
•
•
•
•
•
Collection and compilation of data
Laboratory
Analysis and interpretation
Follow-up action
Feedback
Monitoring
The supervision visit
• Activities during the visit




Use checklist
Observe
Review records
Conduct focus group discussions with staff
• Provide feedback
 Underline achievements
 Mention opportunities for improvement
• Recommend actions with a time frame
Supervision
Go back to your district and be an active
District Surveillance officer
Systematically, collect, transmit, analyze and
feedback public health data for decision
making
Data
Information
Analysis
Action
Interpretation
Surveillance
Your assignment for the next two weeks
•
•
•
•
Go back to your district
Pick up one disease of public health interest
Analyze the data by time, place and person
Produce a report with:
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
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1 page of text, with conclusions and recommendations
1 graph of incidence over time
1 map
1 table of incidence by age and sex
• Share locally and send us a copy within 2 weeks!
 We will give you feedback!
• Use the data for action and make it a habit!
Supervision