system
Medical AI Inquiry: You were designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.
user
Regarding point sources epidemic, which is true?
assistant
The correct answer is  The main features The epidemic curve rises and falls rapidly with no secondary waves The epidemics tend to be explosive there is a clustering of disease within a narrow interval of time All cases develop within one incubation period (refer park pano:64 23rd edition)