Surveillance

Establishing a surveillance system

1. establish goals 2. develop case definitions 3. select appropriate personnel 4. acquire tools and clearances for collection, analysis, and dissemination 5. implement surveillance system 6. evaluate surveillance system

Emerging methods of surveillance

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Types of Surveillance

Sentinel - prearranged sample of reporting sources - uses limited resources, enables prompt mointoring Periodic population-based surveys Lab-based surveillance Integrated disease surveillance and response - links epi and lab data in communicable disease surveillance systems at all levels of health sysem

Integrated surveillance

a combination of active and passive systems using a single infrastructure that gathers information about multiple diseases or behaviors of interest to several intervention programs (for example, a health facility-based system may gather information on multiple infectious diseases and injuries). Managers of disease-specific programs may be evaluated on the results of the integrated system and should be stakeholders. Even when an integrated system is functioning well, program managers may continue to maintain categorical systems to collect additional disease-specific data and Chapter 53Public Health Surveillance: A Tool for Targeting and Monitoring Interventions Nsubuga P, White ME, Thacker SB, et al. Publication Details Image ch53fu1.jpg "What gets measured gets done." —Anonymous Public health surveillance is the ongoing systematic collection, analysis, and interpretation of data, closely integrated with the timely dissemination of these data to those responsible for preventing and controlling disease and injury (Thacker and Berkelman 1988). Public health surveillance is a tool to estimate the health status and behavior of the populations served by ministries of health, ministries of finance, and donors. Because surveillance can directly measure what is going on in the population, it is useful both for measuring the need for interventions and for directly measuring the effects of interventions. The purpose of surveillance is to empower decision makers to lead and manage more effectively by providing timely, useful evidence. Increasingly, top managers in ministries of health and finance in developing countries and donor agencies are recognizing that data from effective surveillance systems are useful for targeting resources and evaluating programs. The HIV and severe acute respiratory syndrome (SARS) epidemics underscored the critical role of surveillance in protecting individual nations and the global community. For example, in 2005, China rapidly began to expand its surveillance and response capacity through its Field Epidemiology Training Program (FETP); Brazil and Argentina chose to use World Bank loans to develop surveillance capacity; and the U.S. Agency for International Development (USAID) redesigned its surveillance strategy to focus on the use of data to improve public health interventions (USAID 2005). Additionally, the guidelines for implementing the 2004 draft revised International Health Regulations require World Health Organization (WHO) member states to have key persons and core capacities in surveillance (http://www.who.int/csr/ihr/howtheywork/faq/en/#draft). Just as decision makers require competent, motivated economists to provide quality technical analyses, they also need competent staff members to provide scientifically valid surveillance information and communicate the results as information for action. Competent epidemiologists and surveillance staff members are not a luxury in developing countries; they are a necessity for rational planning, implementation, and intervention (Narasimhan and others 2004). Definitions and Basic Concepts In this chapter, we use the following definitions: Indicator: a measurable factor that allows decision makers to estimate objectively the size of a health problem and monitor the processes, the products, or the effects of an intervention on the population (for example, the number of new cases of diarrhea, the proportion of children fully immunized in a district, or the percentage of high school students who report that they smoke at least one cigarette a day). Active surveillance: a system employing staff members to regularly contact heath care providers or the population to seek information about health conditions. Active surveillance provides the most accurate and timely information, but it is also expensive. Passive surveillance: a system by which a health jurisdiction receives reports submitted from hospitals, clinics, public health units, or other sources. Passive surveillance is a relatively inexpensive strategy to cover large areas, and it provides critical information for monitoring a community's health. However, because passive surveillance depends on people in different institutions to provide data, data quality and timeliness are difficult to control. Routine health information system: a passive system in which regular reports about diseases and programs are completed by public health staff members, hospitals, and clinics. Health information and management system: a passive system by which routine reports about financial, logistic, and other processes involved in the administration of the public health and clinical systems can be used for surveillance. Categorical surveillance: an active or passive system that focuses on one or more diseases or behaviors of interest to an intervention program. These systems are useful for program managers. However, they may be inefficient at the district or local level, at which staff may need to fill out multiple forms on the same patient (that is, the HIV program, the tuberculosis program, the sexually transmitted infections program, and the Routine Health Information System). At higher levels, allocating the few competent surveillance experts to one program may leave other programs under-served, and reconciling the results of different systems to establish the nation's official estimates may be difficult. Integrated surveillance: a combination of active and passive systems using a single infrastructure that gathers information about multiple diseases or behaviors of interest to several intervention programs (for example, a health facility-based system may gather information on multiple infectious diseases and injuries). Managers of disease-specific programs may be evaluated on the results of the integrated system and should be stakeholders. Even when an integrated system is functioning well, program managers may continue to maintain categorical systems to collect additional disease-specific data and control the quality of the information on which they are evaluated. This practice may lead to duplication and inefficiency.

Indicator factor

a measurable factor that allows decision makers to estimate objectively the size of a health problem and monitor the processes, the products, or the effects of an intervention on the population (e.g. number of new diarrhoael cases)

Health information and management system

a passive system by which routine reports about financial, logistic, and other processes involved in the administration of the public health and clinical systems can be used for surveillance.

Routine Health Information System

a passive system in which regular reports about diseases and programs are completed by public health staff members, hospitals and clinics

Passive Surveillance

a system by which a health jurisdiction receives reports submitted from hospitals, clinics, public health units, or other sources. Passive surveillance is a relatively inexpensive strategy to cover large areas, and it provides critical information for monitoring a community's health. However, because passive surveillance depends on people in different institutions to provide data, data quality and timeliness are difficult to control.

Active Surveillance

a system employing staff members to regularly contact heath care providers or the population to seek information about health conditions. Active surveillance provides the most accurate and timely information, but it is also expensive.

Categorical surveillance

an active or passive system that focuses on one or more diseases or behaviors of interest to an intervention program. These systems are useful for program managers. However, they may be inefficient at the district or local level, at which staff may need to fill out multiple forms on the same patient (that is, the HIV program, the tuberculosis program, the sexually transmitted infections program, and the Routine Health Information System). At higher levels, allocating the few competent surveillance experts to one program may leave other programs under-served, and reconciling the results of different systems to establish the nation's official estimates may be difficult.

Syndromic Surveillance

an active or passive system that uses case definitions that are based entirely on clinical features without any clinical or laboratory diagnosis (for example, collecting the number of cases of diarrhea rather than cases of cholera, or "rash illness" rather than measles). Because syndromic surveillance is inexpensive and is faster than systems that require laboratory confirmation, it is often the first kind of surveillance begun in a developing country. However, because of the lack of specificity (for example, a "rash illness" could be anything from the relatively minor rubella to devastating hemorrhagic fevers), reports require more investigation from higher levels. Also an increase in one disease causing a syndrome may mask an epidemic of another (for example, rotavirus diarrhea decreases at the same time cholera increases).

Disaster Surveillance System

establish objectives; developing case definitions; determining data sources; developing simple data collection instruments, field testing the methods, developing and testing the analysis strategy, developing a dissemination plan for the report or results, and assessing the usefulness of the system. Surveillance needs are different in the preimpact, impact, and postimpact phases

MERS Mobile Surveillance

south Korea - tracking phones of potential contacts (2000 people under quarantine) - School closure -