Point source epidemic is:
Ans. (b) Sharp rise and sharp fall in number of casesRef: K. Park 23rd ed. / 64, 93Types of Epidemics* Point source or single exposure epidemics# Sharp rise and sharp fall in number of cases# Clustering of cases in narrow spectrum of time# All cases develop within one incubation period of disease.# Ex: Food poisoning, measles, chicken pox, Bhopal gas tragedy* Common source, continuous or repeated exposure epidemics:# Sharp rise in number of cases# Fall in number of cases is interrupted by secondary waves/peaks# Ex: Contaminated well in a village, Sex worker in a gonorrhea outbreak* Propagated epidemics:# Gradual rise and gradual fall over a long time (tail off)# Results from person to person transmission# Transmission continues till number of susceptible is depleted or they are no longer exposed to infected individuals# Ex: HIV, TuberculosisAlso Know* Endemic: constant presence of a disease in a defined geographical area* Pandemic: epidemic affecting a large population, occurring over a large geographical area.* Sporadic: scattered cases. They are widely separated in space and time and shows little or no connection.