The war against COVID-19 has changed because of the highly contagious delta variant, the U.S. Centers for Disease Control said, proposing a clearer message, mandatory vaccines for health workers and a return to universal masking.
An internal CDC document said the variant, first detected in India and now dominant across the globe, is as contagious as chickenpox and far more contagious than the common cold or flu. It can be passed on even by vaccinated people, and may cause more serious disease than earlier coronavirus strains.
The document, entitled "Improving communications around vaccine breakthrough and vaccine effectiveness," said the variant required a new approach to help the public understand the danger — including making clear that unvaccinated people were more than 10 times more likely than those who are vaccinated to become seriously ill or die.