What is the difference between epidemiology and surveillance

During a public health emergency response, additional monitoring and surveillance activities may include:. Maintaining close links with epidemiologists in agricultural and veterinary disease surveillance is important in promoting awareness of potential environmental hazards and supporting effective exchange of information during outbreaks of zoonotic disease.

You may be trying to access this site from a secured browser on the server. Please enable scripts and reload this page. This is accomplished through the systematic collection and evaluation of morbidity and mortality reports and other relevant health information, and the dissemination of these data and their interpretation to those involved in disease control and public health decision making.

Image Description. Morbidity and mortality reports are common sources of surveillance data for local and state health departments. These reports generally are submitted by health-care providers, infection control practitioners, or laboratories that are required to notify the health department of any patient with a reportable disease such as pertussis, meningococcal meningitis, or AIDS.

Other sources of health-related data that are used for surveillance include reports from investigations of individual cases and disease clusters, public health program data such as immunization coverage in a community, disease registries, and health surveys.

Most often, surveillance relies on simple systems to collect a limited amount of information about each case. Although not every case of disease is reported, health officials regularly review the case reports they do receive and look for patterns among them. These practices have proven invaluable in detecting problems, evaluating programs, and guiding public health action.

While public health surveillance traditionally has focused on communicable diseases, surveillance systems now exist that target injuries, chronic diseases, genetic and birth defects, occupational and potentially environmentally-related diseases, and health behaviors. Since September 11, , a variety of systems that rely on electronic reporting have been developed, including those that report daily emergency department visits, sales of over-the-counter medicines, and worker absenteeism.

As noted above, surveillance provides information for action. One of the first actions that results from a surveillance case report or report of a cluster is investigation by the public health department. The investigation may be as limited as a phone call to the health-care provider to confirm or clarify the circumstances of the reported case, or it may involve a field investigation requiring the coordinated efforts of dozens of people to characterize the extent of an epidemic and to identify its cause.

The objectives of such investigations also vary. Investigations often lead to the identification of additional unreported or unrecognized ill persons who might otherwise continue to spread infection to others. For example, one of the hallmarks of investigations of persons with sexually transmitted disease is the identification of sexual partners or contacts of patients.

When interviewed, many of these contacts are found to be infected without knowing it, and are given treatment they did not realize they needed. Identification and treatment of these contacts prevents further spread. For some diseases, investigations may identify a source or vehicle of infection that can be controlled or eliminated.

For example, the investigation of a case of Escherichia coli OH7 infection usually focuses on trying to identify the vehicle, often ground beef but sometimes something more unusual such as fruit juice.

By identifying the vehicle, investigators may be able to determine how many other persons might have already been exposed and how many continue to be at risk. When a commercial product turns out to be the culprit, public announcements and recalling the product may prevent many additional cases.

Occasionally, the objective of an investigation may simply be to learn more about the natural history, clinical spectrum, descriptive epidemiology, and risk factors of the disease before determining what disease intervention methods might be appropriate. Early investigations of the epidemic of SARS in were needed to establish a case definition based on the clinical presentation, and to characterize the populations at risk by time, place, and person.

As more was learned about the epidemiology of the disease and communicability of the virus, appropriate recommendations regarding isolation and quarantine were issued.

Public health departments at the federal, state, and local levels use different types of surveillance systems to promote health and prevent disease. These systems can be used to monitor disease trends and plan public health programs.

There are two primary types of disease surveillance: passive and active. Passive disease surveillance begins with healthcare providers or laboratories initiating the reporting to state or local officials. Reportable diseases are submitted on a case-by-case basis, based on a published list of conditions.

In Massachusetts, there are approximately 90 reportable conditions ranging from common infections i. Most of the disease surveillance in Massachusetts is passive. Active disease surveillance is when state or local officials actively search for information by contacting healthcare providers, laboratories, schools, nursing homes, work places, etc. For example, during a cluster investigation of E.