An outbreak refers to the sudden increase in the number of cases of a disease in a specific area or among a particular group of people. This can occur with infectious diseases, such as influenza or COVID-19, and is often identified when the number of cases exceeds what is normally expected. Outbreaks can happen in communities, schools, or even larger regions. Outbreaks can be caused by various factors, including changes in the environment, increased human interaction, or the introduction of a new pathogen. Public health officials monitor outbreaks closely to implement control measures, such as vaccinations or quarantines, to prevent further spread and protect the health of the population.