Regarding point source epidemic, false statement (s) is/are:a) Rapid rise & fallb) Only infectious disease can causec) Explosived) Cases occur even after incubation periode) No secondary wave

Features of point source (single exposure) epidemics The exposure to the disease agent is brief and essentially simultaneous → single exposure. Because disease agent enters into all exposed persons at same time → the resultant cases all develop within one incubation period of the disease. The epidemic curve rises and falls rapidly. Because exposure is single (simultaneous) with no further exposure → No secondary wave (no secondary case). Epidemic tends to be explosive, there is clustering of cases within a narrow interval of time. Point source epidemics are mostly (not always) due to exposure to an infectious agent. Examples → Food poisoning, Bhopal gas tragedy, Minamata disease in Japan, Chernobyl tragedy.