The case for complacency over Covid-19 is clearly narrowing with India recording over 25,000 cases in the week ended Sunday, the highest weekly jump in three months. Though the bulk of the cases are concentrated in Kerala and Maharashtra and the death rate is low, the trajectory of the disease over the past two years suggests that the Centre and the state governments would do well to take preventive action earlier rather than later. The experience of China and Hong Kong points to the dangers of reacting late to the continuing threat of the virus, no matter how relatively non-lethal