Do as your neighbours do? Assessing the impact of lockdown and reopening on the active COVID-19 cases in Nigeria

This paper employs Autoregressive Integrated Moving Average (ARIMA) modelling and doubling time to assess the effect of lockdown and reopening on the active COVID-19 cases (ACC) based on a sample from 29 February to July 3, 2020. Two models are estimated: one with a sample covering post-lockdown period only and another spanning both post-lockdown and post-reopening periods. The first model reveals that the lockdown caused an immediate fall in the daily growth rate of the ACC by 14.30% and 33.26% fall in the long run. The parameters of the second model show that the lockdown had an impact effect of 8.56% and steady state effect of 20.88% reduction in the growth rate of the ACC. The effect of reopening on the ACC is insignificant. However, the doubling time of the ACC has increased after reopening. The study warns against complete reopening until sufficient post-reopening data series is available for exact estimation. The findings in this study can be useful in determining the hospitalisation needs and effectiveness of similar health-related policies.