Novel coronavirus (COVID 19) rapidly spread from China to other parts of the world. Knowledge of incubation period and reproduction number is important in controlling any epidemic. The distribution of these parameters helps estimate the epidemic size and transmission potential of the disease. We estimated incubation period and reproduction number of COVID 19 for India utilizing data reported by Ministry of Health and Family Welfare (MoHFW), Government of India (GOI) and data in public domain. The mean incubation period seems to be larger at 6.93 (SD=5.87, 95% CI: 6.11, 7.75). and 95th percentile estimate for best fit normal distribution is 17.8 days. Weibull distribution, the best fit for the reproduction number estimated pre lockdown reproduction number as 2.6 (95% CI=2.34, 2.86) and post lockdown reduced to 1.57 (95% CI=1.3 , 1.84) implying effectiveness of the epidemic response strategies. The herd immunity is estimated between 36 to 61% for R0 of 1.57 and 2.6 respectively.

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