India’s second Covid wave undermines herd immunity theory
Easing of lockdown restrictions, new variants and reinfections are cited as potential driving factors
India is experiencing a sharp rise in coronavirus infections, increasing pressure on New Delhi to accelerate its vaccine rollout and puzzling scientists after a retreat of the pandemic had buoyed hopes that parts of the country had reached herd immunity.
The nation has reported more than 40,000 daily Covid-19 infections since Friday, up from lows of about 11,000 last month. On Thursday, India reported 53,000 new infections in the past 24 hours, the highest since October...