This document discusses surveillance in healthcare. It defines surveillance as the ongoing collection and analysis of health-related data for public health purposes. The document outlines different types of surveillance including passive, active, and sentinel surveillance. Passive surveillance relies on voluntary reporting while active surveillance stimulates more regular reporting. Sentinel surveillance monitors specific sites. The advantages and disadvantages of each type are provided. The document also discusses important qualities of an effective surveillance system such as simplicity, flexibility, acceptability, sensitivity, predictive value, representativeness, and timeliness.

1. SURVEILLANCE IN HEALTHCARE
BY
KWIZERA DENIS (MBChB)

2. OUTLINE
 WHAT IS SURVEILLANCE
 DIFFERENT TYPES OF SURVEILLANCE
 ADVANTAGES AND DISADVANTAGES OF SURVEILLANCE
 QUALITIES OF A GOOD SURVEILLANCE SYSTEM

3. SURVEILLANCE
 Refers to ongoing, systematic collection, analysis, interpretation and
dissemination of data regarding a health related event for use in
public health action to reduce morbidity and mortality and to improve
health.
 Surveillance provides the information for descriptive epidemiology,
which is
 Person (age, sex, description)
 Place (where)
 Time (dates, hours, days, months, years)

4. IMPORTANCE OF SURVEILLANCE
 Identifying public health emergencies.
 Guide public health policy and strategies.
 Document impact of intervention or progress towards specified public health
targets/goals.
 Understand and monitor the epidemiology of a condition to set priorities and
guide public health policy and strategies
 Detection and notification of health events collection and consolidation of
pertinent data investigation and confirmation(epidemiological clinical and/or
laboratory) of cases or outbreaks routine analysis and creation of reports.

5. CONT,,,,
 Provides feedback of information to those providing the data
 Important in monitoring progress for programs that aim at specific
goals for example polio eradication, measles control or elimination
and maternal and neonatal tetanus elimination.
 Surveillance networks have also been established to provide support
to surveillance sites for specific diseases.

6. TYPES OF SURVEILLANCE
 Passive surveillance
 Passive surveillance is responsible for gathering disease data from all potential
reporting health care workers. Under this type, health authorities do not stimulate
reporting by reminding health care workers to report disease nor providing
feedback to individual health workers.
 Passive surveillance is the most common type of surveillance humanitarian
emergencies. Most surveillance for communicable diseases is passive. The
surveillance coordinator may provide training to health workers in how to
complete the surveillance forms, and may even send someone to periodically
collect forms from health facilities.

7. ADVANTAGES OF PASSIVE SURVEILLANCE
 Little attention is given to individual health workers who report the
information.
 It is inexpensive

8. DISADVANTAGES OF PASSIVE SURVEILLANCE
 There is little access to health facilities and many people fall ill or die at home
without visiting a healthy facilities
 Under recognition of diseases, particularly those that are new to an area or those
with non-specific symptoms.
 Inadequate level of laboratory support in various parts of the world.
 Lack of motivation for reporting when no feedback is provided and a need for
further training.
 There is considerable variation in the quality of reporting system from country to
country, reflecting economic, social, cultural and epidemiological differences.

9. TYPES OF SURVEILLANCE
 Active surveillance
 Refers to regular periodic collection of case reports by telephone or personal visits
to the reporting individual to obtain the data about health.
 An active surveillance system provides stimulus to health care workers in the
form of individual feedback or other incentives. Often reporting frequency by
individual health workers is monitored, health workers who consistently fail to
report or complete the forms incorrectly are provided specific feedback to
improve their performance. Active surveillance requires substantially more time
and resources and is therefore less commonly used in emergencies. But it is often
more complete than passive surveillance. It is often used if an outbreak has begun
or is suspected to keep close track of the number of cases. Community health
workers may be asked to do active case finding in the community in order to
detect those patients who may not come to health facilities for treatment.

10. ADVANTAGES AND DISADVANTAGES OF ACTIVE
SURVEILLANCE
 Advantages of Active surveillance
 More accurate because it is conducted by individuals specifically
employed to carry out responsibility.
 Complete information is given
 Disadvantages of Active surveillance
 Expensive
 Time consuming.

11. TYPES OF SURVEILLANCE
 Sentinel surveillance
 Refers to monitoring key health events through sentinel sites,
events, providers, vectors/animals case report indicates failure of the
health care system or indicates the special problems are emerging.
 A sentinel surveillance system involves selecting either randomly or
intentionally, a small group of health workers from whom to gather
data. These health workers then receive greater attention from health
authorities than would be possible with universal surveillance.
 Sentinel surveillance also requires more time and resources, but can
often produce moe detailed data on cases of illness because the
health care workers have agreed to participate and may receive
incentives.

12. ADVANTAGES AND DISADVANTAGES OF SENTINEL SURVEILLANCE
 Advantages of Sentinel surveillance
 Very cheap
 Disadvantages of Sentinel surveillance
 Applicable only for a select group of diseases.

13. SOURCES OF DATA SURVEILLANCE
 Notifiable diseases
 Laboratory specimens
 Vital records
 Sentinel surveillance
 Registries
 Surveys
 Administrative data systems

14. QUALITIES OF A GOOD SURVEILLANCE
SYSTEM
 Simplicity
 Flexibility
 Acceptability
 Sensitivity
 Predictive value positive
 Representativeness
 Timeliness

15. SIMPLICITY DEFINITION
The simplicity of a surveillance system refers to both its
structure and ease of operation. Surveillance systems should
be as simple as possible while still meeting their objectives.
Methods
A chart describing the flow of information and the lines of
response in a surveillance system can help assess the
simplicity or complexity of a surveillance system.

16. FLEXIBILITY DEFINITION
 A flexible surveillance system can adapt to changing information needs or
operating conditions with little additional cost in time, personnel, or allocated
funds. Flexible systems can accommodate, for example, new diseases and health
conditions, changes in case definitions, and variations in reporting sources.
Methods
 Flexibility is probably best judged retrospectively, by observing how a system
responded to a new demand. For example, when acquired immunodeficiency
syndrome (AIDS) emerged in 1981, the existing notifiable disease reporting
system of state health departments was used to report cases, and AIDS
surveillance has adapted to rapidly advancing knowledge about the disease, its
diagnosis, and its risk factors. Another example is the capacity of the gonorrhea
surveillance system to accommodate special surveillance for penicillinase-
producing Neisseria gonor- rhoeae.

17. ACCEPTABILITY DEFINITION
 Acceptability reflects the willingness of individuals and organizations to
participate in the surveillance system. Methods
 In terms of evaluating a surveillance system, acceptability refers to the
willingness to use the system by:
 a) persons outside the sponsoring agency, e.g., those who are asked to do
something for the system and
 b) persons in the sponsoring agency that operates the system. To assess
acceptability, one must consider the points of interaction between the system and
its participants, including persons with the condition and those reporting cases.

18. SENSITIVITY DEFINITION
The sensitivity of a surveillance system can be considered
on two levels. First, at the level of case reporting, the
proportion of cases of a disease or health condition
detected by the surveillance system can be evaluated. In
Table 1 this is represented by A/(A+C). Second, the
system can be evaluated for its ability to detect epidemics.

19. PREDICTIVE VALUE POSITIVE DEFINITION
 Predictive value positive (PVP) is the proportion of persons identified as having
cases who actually do have the condition under surveillance. In Table 1 this is
represented by A/(A+B). Methods
 In assessing PVP, primary emphasis is placed on the confirmation of cases
reported through the surveillance system. Its effect on the use of public health
resources can be considered on two levels. At the level of an individual case, PVP
affects the amount of resources used for case investigations. For example, in
some states every reported case of type A hepatitis is promptly investigated by a
public health nurse, and family members at risk are referred for prophylactic
treatment with immune globulin. A surveillance system with low PVP--and
therefore frequent "false-positive" case reports--would lead to wasted resources.

20. REPRESENTATIVENESS DEFINITION
 A surveillance system that is representative accurately describes a)
the occurrence of a health event over time and b) its distribution in
the population by place and person. Methods
 Representativeness is assessed by comparing the characteristics of
reported events to all such actual events. Although the latter
information is generally not known, some judgment of the
representativeness of surveillance data is possible, based on
knowledge of:

21. TIMELINESS DEFINITION
 Timeliness reflects the speed or delay between steps in a surveillance system.
Methods
 The major steps in a surveillance system are shown in Figure 2. The time interval
linking any two of the steps in this figure can be examined. The interval usually
considered first is the amount of time between the onset of an adverse health
event and the report of the event to the public health agency responsible for
instituting control and prevention measures. Another aspect of timeliness is the
time required for the identification of trends, outbreaks, or the effect of control
measures. With acute diseases, the onset of symptoms is usually used. Sometimes
the date of exposure is used. With chronic diseases, it may be more useful to look
at elapsed time from diagnosis rather than to estimate an onset date.

22. REFERENCES
 McNabb S et al. Conceptual framework of public health surveillance and action
and its application in health sector reform. Biomed Central Public Health, 2002,
2:2.
 Kimball AM, Thacker SB, Levy ME. Shigella surveillance in a large metropolitan
area: assessment of a passive reporting system. Am J Public Health 1980;70:164-
6.
 CDC, https://www.cdc.com/surveillance/
 WHO, https://www.who.int/search?query=advantages+od+passive+surveillance/