Surveillance system type, steps in planning a system.ppt

Premises of Reinventing
Government
• What gets measured gets done.
• If you don't measure results, you can't tell success
from failure.
• If you can't see success, you can't reward it.
• If you can't reward success, you're probably
rewarding failure.
• If you can't see success, you can't learn from it.
• If you can't recognize failure, you can't correct it.
• If you can demonstrate success, you can win public
support.

SCHEME OF PRESENTATION
• DEFINITION
• TYPES
• ELEMENTS
• USES
• STEPS IN PLG
• ATTRIBUTES
• EVALUATION

Surveillance
“Surveillance, when applied to a disease, means the
continued watchfulness over the distribution, and trends
of the incidence, through the systematic collection,
consolidation and evaluation of morbidity, mortality and
other health relevant data, as well as regular
dissemination of interpretations to all who have
contributed and to all those who are in a position to take
action”.
“information for action”.
(Suggested by Alexander Langmuir and adopted by WHO in 1968)

Surveillance Vs Monitoring
Surveillance
Is the ongoing systematic
collection, collation, analysis and
interpretation of data; and the
dissemination of information to
those who need to know in order
that action may be taken
• Concerns mostly general
populations
• Req professional Analysis &
judgement
Monitoring
Refers to ongoing measurements
of health services or a health
programme with a view to
‘evaluate’ the particular
programme / service or
intervention, with constant
adjustment of performance in
relation to the results.
• Applies to specific target gps
(e.g. Vaccinated infants)
• Can be carried out by technicians
& Instrumentation
• A part of surveillance

HISTORY
• Late 1600s: von Leibnitz – mortality report analysis
• 1680s- John Graunt: ‘Natural and Political Observations
made Upon Bills of Mortality’ – defines disease specific
death counts and rates
• 1700s: Vital Stats used in Europe
• 1741--Rhode Island--Tavern keepers reporting contagious
diseases
• 1840-1850: Chadwik – demonstrates relationship between
poverty, env conditions and diseases
• Late 1800s: Notifiable disease concept
• 1850--Lemuel Shattuck--Report of the Massachusetts
Sanitary Commission.

HISTORY
• 1925: All US states - national morbidity reporting
• 1935: First national health Survey – US
• 1943: cancer registry – Denmark
• 1940s: Case definition concept implemented
• 1955: Active surv for polio
• 1963: Langmuir – modern concept of Surv in Pub Hlth
• 1960s: Network of ‘Sentinel’ GPs in UK; Surv used
for Small Pox eradication
• 1980s: IT in Surv – Decentralization, Dissemination
• 1990: Internet – transit & report; Inc concern reg
Privacy, confidentiality
• 2001: Syndromic Surveillance - Anthrax

PURPOSE
• Three generic purposes
– Identify public health problems
– May stimulate public health intervention
– May suggest hypotheses for research

Types of Surveillance
• Passive surveillance – a system in which data
generated without solicitation, intervention or
contact by the health agency carrying out the
surveillance. Other agencies initiate reporting.
• Active surveillance – the organization
conducting surveillance initiates procedures to
obtain reports

Types of Surveillance contd.
• Enhanced passive surveillance – active follow
up of cases to pursue other possible
causes/cases
– e.g. contact tracing in STD
• Sentinel Surveillance - Surveillance system in
which reports are obtained from certain facilities
or populations

11
Syndromic Surveillance
• Syndromic surveillance systems face inherent
trade- offs (among sensitivity, and the number
of false positives) timeliness, that limit their
effectiveness
• The benefits of any Syndromic surveillance
system will depend on how effectively it is
integrated into the public health system
• Syndromic surveillance is useful: (suspected
outbreaks and during outbreaks; depends on case definitions)

12
Surveillance of Disease vs. Persons
• Surveillance of Disease:
“ The continuing scrutiny of all aspects of
occurrence and spread of disease that are
pertinent to its effective control”
• Surveillance of Persons:
“ The continuing scrutiny of disease contacts,
high risk groups in order to promote prompt
recognition of infection or illness”

13
Surveillance various levels
• Individual Surveillance
• Local population Surveillance
• National Population Surveillance
• International Surveillance

14
• Immidiate
• Epidemics
• Newly emerging health problems
• Changes in health practices
• Changes in antibiotic resistance
• Annual
• Estimating magnitude of health problems
• Assessing control activities
• setting research priorities
• Testing hypothesis
• Facilitate plg
• Archival
• Describing natural history of a disease
• Facilitate epidemiolgic research
• Validating use of preliminary data
• Documenting dist of spread
SURVEILLANCE ACCORDING TO
TIMELINESS

15
• Natural and man-made disasters
(emergencies)
• During Special events of mass gatherings
– Pilgrims to Makkah
– Olympics
• Laboratory-based surveillance:
– Emerging pathogens
– Antimicrobial resistance
• Infection control
• Behavioural risk factors
• Others
Special Surveillance Programs

16
Exposed
Clinical specimen
Disease
+ve specimen
Infected
Seek medical attention
Reported
Laboratory-based
surveillance
Syndromic
Surveillance
Serological surveys
We see only
reported
cases

Simplified Diagram of Surveillance for a Health Problem

Information Loops
• A surveillance system is an information loop or
cycle that involves:
– healthcare providers
– public health agencies
– the public
# 1-4-5

Flow of
Surveillance Data
Collection
Analysis and
Interpretation
Dissemination, Utilisation
Collation
# 1-4-6

•Surveillance is systematic ongoing
collection, collation, and analysis of data, and
the timely dissemination of information to
those who need to know so that action can
be taken
•A survey is a one data collection episode
•Registries are not for immediate action
•Health Management Information Systems
(HMIS) for annual reports
Surveillance, surveys, registries and HMIS:

21
• Registers are archival health information
• Surveillance is dynamic as compared with
surveys: Interplay between epidemiologic
studies and control activities
• Surveillance is not mere:
– Reporting
– Monitoring
– Data collection
Note the Differences:

ELEMENTS OF SURVEILLANCE
• Cycle of Surveillance
• Confidentiality
• Incentives to Participation
• Surveillance Ethics
• legitimate desire to protect privacy
• Stigma

Avian Flu, EU
$500m
1996 1997 1998 1999 2000 2001 2002 2003
$50bn
$40bn
$30bn
$20bn
$10bn
Estimated
costs
BSE, UK
$10-13bn Foot&Mouth Disease
Taiwan, $5-8bn
1992 1993 1994 1995
Foot-and-Mouth Disease
UK
$30bn
Avian Flu
Asia, US, Canada
$10bn
2004
BSE, US
$3.5bn
BSE, Canada
$1.5bn
Lyme disease
US, $2.5bn
SARS
China, Hong Kong,
Singapore, Canada,…
$50bn+
Nipah, Malaysia
$350-400m
Swine Flu,
Netherlands
$2.3bn
BSE,
Japan
1.5bn
Economic Impact of
Recent Epidemics

24
• “ Ultimately a single
element, a single addition to
the strategy of the
[eradication] program was
responsible [for its success]
.. that change was the
incorpotation of the principle
of surveillance”
D. A. Henendersen
Smallpox Eradication

Rationale for Disease Surveillance
The disease is of public health importance
• Caution!
– Is it worth the effort (money, human
resources)?
– Are relevant data easily available?
– Can action be taken?

Objectives of surveillance
DESCRIPTIVE EPID OF HEALTH PROBLEMS
• Monitoring trends (Time):
Measles in US
• Person Distribution:
Groups at highest risk of disease
Insight into etiologies, modes of spread
Guide Prev activities before etiology known
e.g. Surv AIDS – sexual, drug and medical
history

• Epidemic / outbreak detection and prediction:
Syndromic surveillance – bioterrorism related
epidemics
non specific syndromes (resp, GI..),
other measures (purchase of drugs,
absenteeism..)
• Place Distribution: Maps

• Estimate magnitude of health problem
• Changes in health practices
– e.g. Caesarian deliveries
• Distribution and spread in time & Place
• Natural history

LINKS TO SERVICES
Integral part of delivery of prev & therapeutic
services
Receipt of a case report triggers specific response
e.g. TB case – to cure, minimize transmission,
prevent resistance, contact identification
LINKS TO RESEARCH
Insufficient details for probing in-depth hypothesis,
Hypothesis generating
e.g. studies assoc TSS with tampon

EVALUATION OF INTERVENTIONS
Trends, Rates
Monitor programme performance e.g. TSS cases
fell after removal of tampon from market.
PLANNING & PROJECTIONS
Planners need future demands for health services
Epidemiological models
Applying current disease rates to future
population projectons

EDUCATION & POLICY
Alert physicians to community health problems
Inform policy makers about
prevention or care resources requirement

Uses of Public Health Surveillance
• Estimate magnitude of the problem
• Portray the natural history of a disease
• Determine distribution and spread of illness
• Detect outbreaks
• Generate hypotheses, stimulate research
• Evaluate control and prevention measures
• Monitor changes in infectious agents
• Detect changes in health practices
• Facilitate planning

Uses of Public Health Surveillance
• Estimate magnitude of the problem
• Portray the natural history of a disease
• Determine distribution and spread of illness
• Detect outbreaks
• Generate hypotheses, stimulate research
• Evaluate control measures
• Monitor changes in infectious agents
• Detect changes in health practices
• Facilitate planning

Shigellosis
1968-1998
0
5
10
15
Year
1968 1973
197
8 1983 1988 1993 1998
Reported
cases
per
100,000
population
Source: CDC. Summary of notifiable diseases. 1998.

TOXIC SHOCK SYNDROME (TSS)
United States, 1983-1998
*Includes cases meeting the CDC definition for confirmed and probable cases for staphylococcal TSS.
1983 1984 1985 1986 1987 1988 1989 1990 1991 1992 1993 1994 1995 1996 1997 1998
National Center for Infectious Diseases (NCID) data*
National Electronic Telecommunications System for
Surveillance (NETSS) data
0
2
0
4
0
6
0
8
0
10
0
12
0
14
0
16
0
Year (Quarter)
Reported
cases

Evolution of an Epidemic
Estimated AIDS incidence* through 2000, United States
*Estimated from data reported to CDC through June 2001, adjusted for reporting delays.
0
10000
20000
30000
40000
50000
60000
70000
80000
90000 1
9
8
2
1
9
8
4
1
9
8
6
1
9
8
8
1
9
9
0
1
9
9
2
1
9
9
4
1
9
9
6
1
9
9
8
2
0
0
0
Year of Diagnostics
Number
of
Cases
Serologic assay for HIV
antibody available
HIV identified
AIDS case definition
expanded
AZT shown to reduce risk
of perinatal transmission
Protease inhibitors
licensed for use in US
100,000 AIDS cases reported
to CDC as of July 1989.
500,000 AIDS cases
reported to CDC as
of October 1995
An estimated 798,500
AIDS cases diagnosed
through 2000
Use of HAART becomes
widespread.
AZT monotherapy
becomes available
AIDS case definition modified
First AIDS case definition published

Rate of Hepatitis A
United States, 1998
< 5.0 5.0–9.9 10.0–19.9 >20.0
NA
NA
NA
NYC
DC
PR
VI
GUAM
AM SAMOA
CNMI

Botulism (Foodborne)
*Data from survey of state epidemiologists and directors of state public health laboratories.
Not yet available for 1998.
Outbreak caused by
potato salad, NM Outbreak caused by
sautéed onions, IL
Outbreak caused by
fermented fish/sea
products, AK
Outbreak caused by
baked potatoes, TX
Laboratory-confirmed
cases*
NETSS data
0
10
20
30
40
50
60
70
80
90
100
110
Year
1978 1983 1988 1993 1998
Reported
cases

Year
Reported
cases
(thousands)
Vaccine licensed
0
50
100
150
200
250
300
350
400
450
500
1963 1968 1973 1978 1983 1988 1993 1998
MEASLES — by year, United States, 1983–
1998
0
5
10
15
20
25
30
Year
1983 1988 1993 1998
Reported
Cases
(Thousands)
MEASLES (Rubeola)

Poliomyelitis (Paralytic)
NOTE: Inactivated vaccine was licensed in 1955. Oral vaccine was licensed in 1961.
Year
0
5
10
15
20
25
30
35
40
45
50
55
60
1968 1973 1978 1983 1988 1993 1998
Reported
cases
Rate/100,000
Population
Year
Inactivated
Vaccine
Oral
Vaccine
0.001
0.01
0.1
1
10
100
1000
1951 1956 1961 1966 1971 1976 1981 1986 1991 1996

Trends in Plasmid-Mediated Resistance to
Penicillin and Tetracycline
Source:
Gonococcal Isolate
Surveillance Project
(GISP)
Percent
0
2
4
6
8
10
12
1988 1989 1990 1991 1992 1993 1994 1995 1996 1997
PPNG
TRNG
PPNG & TRNG
Note: "PPNG" (penicillinase-producing ) and "TRNG" (tetracycline-resistant) N. gonorrhoeae refer to plasmid-
mediated resistance to penicillin and tetracycline, respectively.
Year

Foreign-born
Year
U.S.-born
1986 1987 1988 1989 1990 1991 1992 1993 1994 1995 1996 1997 1998
0
4,000
8,000
12,000
16,000
20,000
Reported
cases
Tuberculosis
(U.S.- and foreign-born persons)

53
Early Warning (EWARN):
An important Component of Surveillance Systems
• Rumour verification
• EWARNs
 Detect clusters in time, place or persons
 Change in trend
• Programme monitoring
 Programme indicators
• Surveillance system monitoring
 Operation indicators
 Support indicators
 Output indicators
Requiring
immediate
investigation
Requiring
programme
adjustment
Requiring
system
improvement
Requiring
verification

Early Warning Signals
Clustering of cases or deaths in time & /or space
Unusual increase in cases/ deaths
• Ac. hemorrhagic fever
• Ac. fever with altered sensorium/ renal
involvement/ painful lymph node/ unknown
aetiology
• Severe dehydration following diarrhoea in
patients
> 5 year of age
• Ac. flaccid paralysis in a child

Early Warning Signals - II
2 or more linked cases
• Even a single case of epidemic prone
diseases in tribal/poorly accessible area
• Unusual isolate in laboratory
• Shift in age distribution of a disease
• High vector density in local area
• Natural disasters

Surveillance for Outbreak Detection
• Convergence of technology, volumes of
electronic data, and new priority for early
detection
• Increase timeliness and completeness of
routine data
• Capture nontraditional data that signify a
condition before a diagnosis is made
• Analytic methods to detect smaller signals

Surveillance for Outbreak Detection:
Experience
• Laboratory specificity to detect clusters
• Sentinel systems with resources to monitor
and investigate
• Syndrome surveillance where outbreaks are
substantial and predictable
• Case reports trigger outbreak investigation

Exploration
• Enhanced reporting from clinical sites (ED,
EMS, 911, offices)
• Health care transaction warehouses
(pharmacy, patient encounters, lab orders)
• Novel data sources (retail sales, veterinary
encounters, environmental indicators,
absenteeism)
• Signal detection methods

Reality
• Human “technology” is key
– Single case detection depends on clinical
acumen and reporting relationships
– Epidemiologic judgment in evaluating
volumes of data
– Follow-up of system signals
• Tolerance for false alarms will vary

Surveillance functions
Core function
• Reporting
• Detection
• Investigation & confirmation
• Analysis & interpretation
• Action / response
Support function
• Training
• Supervision
• Resources
• Standards / guidelines

Steps in planning a
surveillance system
Decide if justifiable
Establish objectives
Specify organization and structure
Develop case definition
Specify the details of collection of information
Organization and procedures of data analysis
Making scientific interpretations
Ensure proper feedback
Evaluation
Assure use of analysis and interpretation

• Frequency of occurrence
• Severity of condition
– sequel, disabilities
• Cost of surveillance
• Preventability of condition
• Communicability of condition
– potential for an outbreak
• Public interest
– public perception and concern
• International requirements.
Determine Priority/Importance
Steps in planning

Ability to prevent, control, or treat the health problem
• preventability and
• control measures and treatment.
Capacity of health system to implement control
measures for the health problem —
• speed of response,
• economics,
• availability of resources, and
• what surveillance of this event requires.
Determine Priority/Importance
contd..
Steps in planning

Case definition
• Clinical versus laboratory
– Balance competing needs of
• Sensitivity
• Specificity and
• feasibility
• Level of case definition (suspected, probable, confirmed)
Example Influenza:
– Suspected: A person with sudden onset of fever > 39C, respiratory symptoms,
myalgias, headaches
– Probable: A suspected case , epidemiologically linked to laboratory-confirmed
case
– Confirmed: A suspected case with virus isolation or direct antigen detection
Steps in planning

Collection of information
Data source
• Disease notifications and Notifiable diseases
• vital statistics
• Vital record linkages
• Health reports
• Hospital records/ health centers
• Laboratory
• Disease registries
• Health surveys
• Studies on animals & vectors
Steps in planning

Data source contd
• Member of the public, media
• Socio-demographic & environmental data
• Co-operating Physicians
• Absenteeism from workplace & School
• Administrative actions
• Financial transactions
– Sales of goods & services
– Taxation
• Legal actions
• Law and regulations
Steps in planning

72
• Method of data collection
–Active Surveillance:
–Passive Surveillance:
–Sentinel surveillance
–Volunteer providers
–Special surveillance team
Steps in planning

73
• Forms used – simple & brief
• What time/ place of diagnosis entered
• Frequency of reporting
– Daily ( cholera, food poisoning)
–Weekly ( Malaria)
–Monthly ( HIV)
• Method of transmission of reports
• Central collection of data
Steps in planning

TYPES OF NOTIFICATIONS
1. Disease or hazard-specific notifications
a. Communicable diseases
i. World Health Organization: International health regulations require
reporting of Smallpox, Poliomyelitis ,Human influenza, SARS etc.
ii. National: United States and Canada specify diseases that require
notification by all states and provinces, respectively
iii. Provincial, state, or subnational: for example, coccidiomycosis in
California
b. Chemical and physical hazards in the environment
i. Childhood lead poisoning
ii. Occupational hazards
iii. Firearm-related injury
iv. Consumer product-related injury
Adapted from: Koo D, Wingo P, Rothwell C. Health Statistics from Notifications, Registration Systems, and Registries.

TYPES OF NOTIFICATIONS contd.
2. Notifications related to treatment administration
a. Adverse effect of drugs or medical products
b. Adverse effect from vaccines
3. Notifications related to persons at risk
a. Elevated blood lead among adults
b. Elevated blood lead among children
Adapted from: Koo D, Wingo P, Rothwell C. Health Statistics from Notifications, Registration
Systems, and Registries. In: Friedman D, Parrish RG, Hunter E (editors). Health Statistics:
Shaping Policy and Practice to Improve the Population’s Health. New York: Oxford University
Press; 2005, p. 82.

TYPESOF REGISTRIES
1. Vital event registration
a. Birth registration
b. Marriage and divorce registration
c. Death registration
2. Registries used in preventive medicine
a. Immunization registries
b. Registries of persons at risk for selected conditions
c. Registries of persons positive for genetic conditions
3. Disease-specific registries
a. Blind registries
b. Birth defects registries
c. Cancer registries
d. Psychiatric case registries
e. Ischemic heart disease registries
Adapted from: Koo D, Wingo P, Rothwell C. Health Statistics from Notifications, Registration Systems, and Registries.
In: Friedman D, Parrish RG, Hunter E (editors). Health Statistics: Shaping Policy and Practice to Improve the
Population’s Health. New York: Oxford University Press; 2005, p. 91

TYPESOF REGISTRIES contd.
4. Treatment registries
a. Radiotherapy registries
b. Follow-up registries for detection of iatrogenic thyroid disease
5. After-treatment registries
a. Handicapped children
b. Disabled persons
6. Registries of persons at risk or exposed
a. Children at high risk for developing a health problem
b. Occupational hazards registries
c. Medical hazards registries
d. Older persons or chronically ill registries
e. Atomic bomb survivors (Japan)
f. World Trade Center survivors (New York City)
7. Skills and resources registries
8. Prospective research studies

79
• Weekly? Appropriate most times
• Monthly? Less sensitive
• Quarterly? At national level
• Daily?
– Daily reporting could be cumbersome
– Daily reporting may be required during emergencies,
disasters
• Avoid inconsistencies in case definitions
• Reporting suspected vs. confirmed cases
Frequency of Reporting Diseases

Analysis, Interpretation & Presentation of
Surveillance data
• Attribution of Time
• Attribution of Place; use of GIS
• Attribution of persons
• Detection of change in trends
• Assessing Completeness of surveillance
Capture-Recapture
Steps in planning

Surveillance data
Inferential statistics :
Analytic procedures usually are based on
comparing the current incidence against the
“Upper and Lower Control Limits”
Steps in planning

Surveillance data
• Smoothing
• Protection of confidentiality
Presentation
• Wide range of Users
• Mode of presentation – intended audience
Steps in planning

Common causes of artifactual changes
• Changes in local reporting procedures or policies
(e.g., a change from passive to active surveillance).
• Changes in case definition
(e.g., AIDS in 1993).
• Increased health-seeking behavior
(e.g., media publicity prompts persons with symptoms
to seek medical care).
• Increase in diagnosis.
• New laboratory test or diagnostic procedure.

Common causes of artifactual changes
contd.
• Increased physician awareness of the condition,
or a new physician is in town.
• Increase in reporting
(i.e., improved awareness of requirement to report).
• Outbreak of similar disease, misdiagnosed as
disease of interest.
• Laboratory error.
• Batch reporting in which reports from previous
periods are held and reported all at once during
another reporting period
(e.g. reporting all cases received during December and
the 1st week of January during the second week of

Dissemination mechanism
Directly to all who need to know
• Press release to the public
• Reports, bulletins
• Others
Steps in planning

Assure use of analysis and
interpretation
Control measures
– rapid response
– case management
– prevention programme (immunisation)
Planning/ policy making
– epidemic preparedness
– policy modification
– prediction and future planning
Feedback to the system
Steps in planning

Periodically evaluate/review the
surveillance system
For
• Completeness
• Accuracy
• Process and
• Adequacy
To See
Whether the case definitions need a change?
Problems in the timely and accurate reporting and how
can it be improved?
Defects and reorient the methodology.
Steps in planning

Public Health Surveillance
System Attributes
• Simplicity
• Flexibility
• Data Quality
• Acceptability
• Sensitivity
• Predictive Value
Positive
• Representativeness
• Timeliness
• Stability

Check List for Assessing an
Established Surveillance
System
1. Broad goals & objectives
2. Adequate Staffing
Adequate training
3. The diseases under surveillance
Sensitivity & specificity of the diagnostic criteria and
case – definitions
Are facilities for diagnosing available?

System
4. The sources of information
Are the persons proficient in recording the
case definitions?
Feasibility of forms used by the peripheral workers
5. Timely reporting
6. How much is the under - or over - reporting?
7. Maintenance of manual and automated files

System
8. The time lag between receipt of reports and
generation of analysed feedback reports.
9. Are the reports generated simple and presentable ?
Are they forwarded to all concerned
10. Has the information been actually used
11. Is the surveillance system periodically evaluated

The International Health Regulations (IHR):
A global framework
• Legally-binding global agreement to protect public health
• The international commitment for shared responsibilities
and collective defence against disease spread
• Collective effort based on agreed rules
Smallpox,
1950s

International public health security is the
goal
Ensuring maximum public health
security
while minimizing interference with
international transport and trade
Come into force on 15 June 2007*
Legally binding for WHO and the world’s countries that have
agreed to play by the same rules to secure international health.
Legally binding upon 194 States Parties around the world
(including all WHO Member States)

From control of borders to (also) containment at source
From diseases list to all threats
From preset measures to adapted and real time response
IHR(2005): a paradigm shift

Strategic framework
• Communication and exchange of
information
• Coordination
• Joint cross-boarder surveillance and
outbreak investigation
• Resources sharing and mobilization
• Standardization and sharing surveillance
tools
• Laboratory network
• Preparedness and response to outbreaks
• Capacity building
• Social mobilization
• Monitoring and evaluation

99
• Vary from one country to another
– Differences within countries
– Changes over time
• Adding one single disease to the list could
cost a lot: Money, time, avoidable
confusion
• Variables collected should be indicators of
potential or arising problems rather than
identifying risk factors
• Report only confirmed cases?
Reportable Diseases

Past Approaches
• Duplication of efforts and resources
Delays in reporting and identification of
outbreaks
Lack of dissemination and feedback to the
local level
Lack of integration of training and
surveillance activities
# 1-4-13

Common Problems with Past
Surveillance Systems, Cont.
Limited evaluation of programmes
Inadequate involvement of laboratories
Incomplete reporting and lack of supervisory
support
# 1-4-14

Surveillance system type, steps in planning a system.ppt

Surveillance system type, steps in planning a system.ppt

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