As the coronavirus sweeps across the globe in relentless waves, a succession of more-infectious strains has washed up. So far delta, the variant first reported in India in October, is the most worrisome. About twice as transmissible as the original virus that emerged in late 2019, delta combines a multitude of genetic features that have enabled it to pierce public-health defenses to stoke severe epidemics and trigger fresh rounds of movement restrictions or delay planned easings of them.
Coronavirus
Bloomberg: What makes Delta the most disruptive virus variant
People wait for admission outside the emergency ward of a hospital tending to Covid-19 coronavirus patients in Surabaya on July 11, 2021, as Indonesia faces its most serious outbreak driven by the highly infectious Delta variant.
