Which term best describes a disease that occurs rarely and without a regular pattern?

• A. Epidemic
• B. Sporadic
• C. Endemic
• D. Pandemic

Answer: (B)

Sporadic describes disease occurrences that happen irregularly and infrequently, with no predictable pattern or clustering. In this pattern, cases appear scattered in time and place and there isn’t sustained transmission in the population. This contrasts with endemic, where a disease is continually present at a baseline level in a region; epidemic, where there is a sudden increase above the expected number of cases in a defined population over a period; and pandemic, where the increase spans large geographic areas or the entire world. So, a disease that occurs rarely and without a regular pattern is best described as sporadic.