DID LOCK DOWN REALLY LOCKED DOWN THE SPREAD OF COVID-19 SPREAD IN TAMIL NADU?

India had declared the longest lockdown of about 57 days in the nation to prevent the spread of COVID-19 spread. We analysed the efficiency of COVID-19 lockdown in Tamil Nadu with Autoregressive integrated moving average ARIMA (1,1,3)(0,0,0) model. We carried out the analysis with the assumption that, the COVID-19 cases reported till the 14^th day (April 8^th) after the declaration of lockdown would have been acquired before the lockdown period.

W used the data of cumulative cases until April 8th to forecast the cases till May 3rd. The hypothesis tested: If the forecasted cumulative cases were lesser then the real cumulative cases reported, it can be attributed that lockdown was efficient in preventing the spread of the pandemic. Statistical analysis: Moving average range was fixed as 3, Upper and lower confidence limit was also assessed with 95% CI.

Fig: ARIMA based forecasting with Cumulative cases in Tamil Nadu.

The cumulative cases on May 3^rd:3023 Forecasted cumulative case on May 3^rd:2018Forecasted upper confidence limit on May 3^rd: 3495The cumulative cases raised about 49.80% than the forecasted cumulative case by May 3^rd. In contrary the cumulative cases achieved about 86.49% of upper confidence limit by May 3^rd It’s also evident that the cumulative cases were in the range of forecasted range till April 20^th (26^th day of lockdown). 

This analysis proved that a long term lockdown, in a place where there was evidence of a community spread lockdown won’t be efficient in preventing the spread of the pandemic. Since most of the cases are reported from Chennai which is the most populated district in the state (26553 ppl/sq.Km) gives more insight about the impact of population density in the spread of COVID-19. Hence the state will have to research on more interventions to prevent the spread of disease in the state.

Thus in a state where there were prominent evidence of community spread associated with a socio-cultural event the lockdown wouldn’t yield a fruitful result. The lockdown might give a bridging period to develop the medical facilities including testing strategies to meet this highly demanding situation.

Mr. Aby Paul, Pharm.D Intern