A couple has 4 children, all unvaccinated for Measles. A child got Measles on 5 August 2015. Two other children developed Measles by 15 August 2015. Secondary attack rate is:
In the given question, One primary case given rise to two secondary cases Total susceptible = 3 (4 children minus primary case) SAR = No. of secondary cases/ Total susceptibles X 100 So, SAR = 2/3 X 100= 66.6%
0%
33%
66%
75%
Disease Causation, Measurements, Milestones