Epidemic curve

From WikiMD's Wellness Encyclopedia

Epidemic curve is a statistical chart used in epidemiology to visualize the onset of a disease outbreak. It can help to identify the mode of spread of the disease, its time trend, and the population group most affected.

Definition[edit | edit source]

An Epidemic curve or "epi curve" is a histogram that displays the course of an epidemic by plotting the number of cases in a population over time. The horizontal axis represents the date or time of illness onset among cases, while the vertical axis represents the number of cases. Each bar in the graph represents the number of people who developed the disease at each point in time.

Purpose[edit | edit source]

The main purpose of an epidemic curve is to depict the distribution of cases over time. This can help to identify the mode of spread of the disease (whether it is person-to-person, common source, or vector-borne), the time trend (whether the disease is increasing, decreasing, or stable), and the population group most affected (by age, sex, or location).

Construction[edit | edit source]

To construct an epidemic curve, the following steps are typically followed:

  1. Collect data on the number of cases and the date of onset of symptoms.
  2. Plot the number of cases on the vertical axis and the date of onset on the horizontal axis.
  3. Draw bars to represent the number of cases at each point in time.

Interpretation[edit | edit source]

The shape of the epidemic curve can provide clues about the nature of the epidemic. For example, a sharp upward slope followed by a gradual decline often indicates a common source outbreak, while a series of progressively taller peaks may suggest a propagated outbreak.

Limitations[edit | edit source]

While epidemic curves can be a useful tool in epidemiology, they also have limitations. They can only show the number of cases over time, not the severity or duration of the disease. They also cannot show the spatial distribution of cases, which can be important in understanding the spread of the disease.

See also[edit | edit source]

Epidemic curve Resources
Wikipedia
WikiMD
Navigation: Wellness - Encyclopedia - Health topics - Disease Index‏‎ - Drugs - World Directory - Gray's Anatomy - Keto diet - Recipes

Search WikiMD

Ad.Tired of being Overweight? Try W8MD's physician weight loss program.
Semaglutide (Ozempic / Wegovy and Tirzepatide (Mounjaro / Zepbound) available.
Advertise on WikiMD

WikiMD's Wellness Encyclopedia

Let Food Be Thy Medicine
Medicine Thy Food - Hippocrates

Medical Disclaimer: WikiMD is not a substitute for professional medical advice. The information on WikiMD is provided as an information resource only, may be incorrect, outdated or misleading, and is not to be used or relied on for any diagnostic or treatment purposes. Please consult your health care provider before making any healthcare decisions or for guidance about a specific medical condition. WikiMD expressly disclaims responsibility, and shall have no liability, for any damages, loss, injury, or liability whatsoever suffered as a result of your reliance on the information contained in this site. By visiting this site you agree to the foregoing terms and conditions, which may from time to time be changed or supplemented by WikiMD. If you do not agree to the foregoing terms and conditions, you should not enter or use this site. See full disclaimer.
Credits:Most images are courtesy of Wikimedia commons, and templates Wikipedia, licensed under CC BY SA or similar.

Contributors: Prab R. Tumpati, MD