Which one of the following is a good index of the severity of an acute disease?: (A) Case fatality rate, (B) Cause specific death rate, (C) Standardized mortality ratio, (D) Five year survival
Answer is A. Case fatality rate measures the killing power of a disease, for acute infectious diseases like food poisoning, cholera, measles.
It is simply the ratio (it is not  a RATE) of deaths to cases.