i
i
Up-to-date Information
Up-to-Date Info: To find the latest CDC information on this topic go to: cdc:35632
Manual for the surveillance of vaccine-preventable diseases. Chapter 18: Surveillance indicators
Details:
-
Alternative Title:Surveillance indicators
-
Personal Author:
-
Corporate Authors:
-
Description:Chapter 18 of: Manual for the surveillance of vaccine-preventable diseases. 5th edition, 2011.
In routine disease control programs, traditional, passive disease surveillance systems are usually adequate to meet program demands despite their limitations. In contrast, in disease elimination or eradication programs, routine surveillance activities are inadequate once the goal is near. In advanced disease elimination and eradication programs, every case counts. Without adequate surveillance, elimination of vaccine-preventable diseases cannot be achieved and sustained. This chapter describes the surveillance needs for diseases in various stages of prevention and control and discusses surveillance indicators that have been developed to evaluate the appropriateness, completeness, accuracy, and timeliness of surveillance systems.
Traditionally, communicable disease surveillance programs have relied on passive reporting, in which reports are received from physicians and other providers. For diseases and conditions for which laboratory confirmation is routinely obtained, laboratory-based reporting has virtually replaced traditional provider-based reporting in many jurisdictions, because case ascertainment is far more complete. However, even when supplemented by laboratory-based reports, reporting in traditional passive surveillance systems remains incomplete. Despite this limitation, these data remain useful because they are used primarily for monitoring trends in disease occurrence rather than for initiating public health action in response to each individual case.
In disease elimination programs, the role of surveillance is different. To achieve a goal of zero cases of a disease, aggressive efforts must be made to identify factors that allow cases to continue to occur despite the low incidence of disease. The occurrence of these cases may indicate the need for new prevention strategies, but in order to track the impact of any such strategies, surveillance data are essential. In addition, timely notification is necessary so that public health action can be taken to limit spread of disease.
This was illustrated during the global smallpox eradication program. The continued occurrence of cases of smallpox despite high vaccination coverage led to the development of a new strategy for smallpox eradication; i.e., a wide circle of contacts around each case-patient was identified and vaccinated, creating a wall of immunity around the remaining patients. This led ultimately to the global eradication of smallpox. It could not have been achieved without recognition of the need for an additional strategy and without the ability to rapidly identify and respond to individual cases. Andrews and Langmuir wrote in 1963, “To achieve and maintain the eradication status of a specific disease within an area, it is necessary 1) to obstruct transmission until endemicity ceases, and 2) to prevent or nullify the reestablishment of the disease from carriers, relapsing cases, or imported sources of infection. Accordingly, an adequate surveillance organization must be developed to identify and cope with these threats to the achievement of disease eradication.”
chpt18-surv-indicators.pdf
-
Subject:
-
Document Type:
-
Genre:
-
Collection(s):
-
Main Document Checksum:
-
File Type:
Supporting Files
-
No Additional Files
More +