Epidemiological Surveillance & Outbreak Investigation Study Points

Epidemiological Surveillance & Outbreak Investigation study points

Surveillance of disease

- Surveillance is the entire process of collecting, analyzing, interpreting, and reporting data

concerning the incidence of death, diseases, injuries, the prevalence of certain conditions whose knowledge is considered important for promoting the health of the public.

- Feds have jurisdiction over disease outbreaks with interstate implications.

- States have jurisdiction over disease outbreaks with intrastate implications.

Creating a surveillance system

- system requires clear objectives, and the purposes for which the surveillance is to be done.

- Standardization of reporting procedures and forms

-requires the criteria for defining a case of the reportable disease/condition be known.

-The kinds of analyses needed (incidence, prevalence, case fatality ratios, etc) should be stated in advance, and there should be plans for dissemination.

- should be subjected to continual evaluations.

Methods for the surveillance of disease

Passive surveillance: expectation of/from medical community that they will report all cases of reportable diseases.

Active surveillance: requires periodic (usually weekly) contact with reporting individuals/institutions to obtain required data.

1. Establishment of baseline data: usual rates and patterns of disease can be known only if there is a regular reporting and surveillance system.

2. Evaluation of time trends

a) implications of long-term secular/time trends of disease are usually different from those of outbreaks/epidemics, and are often of greater significance.

b) seasonal variation may impact the expected number of cases or rate of disease.

1) infectious dz spread by respiratory route have higher incidence in winter months.

2) infectious dz spread by insect or arthropod vectors have predilection for summer or early fall

3) fecal-oral route are most common in summer

c) because different patterns peak at different times of the year, CDC may show “epidemiologic year”; for a given disease runs from time of lowest incidence in one year to same month next year.

d) other variations: more people