Health Dictionary
Reliable, easy-to-read patient information on common medical conditions — written in plain language, free of jargon, and grounded in current evidence. Browse the most frequent diagnoses, understand what they mean for everyday life, and learn which steps and questions help you have a focused conversation with your doctor.
Outbreak
Introduction
Outbreak is a classification used in epidemiology to describe a small, localized group of people or organisms infected with a disease. Such groups are often confined to a village or a small area. Outbreaks may also refer to epidemics, which affect a region in a country or a group of countries, or pandemics, which describe global disease outbreaks.
Outbreak Investigation
Outbreak Investigation
When investigating disease outbreaks, the epidemiology profession has developed a number of widely accepted steps. As described by the Centers for Disease Control and Prevention, these include the following[1]:
- Identify the existence of the outbreak: is the group of ill persons normal for the time of year, geographic area, etc.?
- Verify the diagnosis related to the outbreak
- Create a case definition to define who/what is included as a case
- Complete descriptive epidemiology: describe outbreak with respect to time, place, and people
- Develop a hypothesis: what appears to be causing the outbreak?
- Study hypothesis: collect data and perform analysis
- Refine hypothesis and carry out further study
- Develop and implement control and prevention systems
- Release findings to greater community