STAT reports:

In some respects, the Delta variant has changed everything in the Covid-19 pandemic. In others, the same rules still apply.

Before the variant of SARS-CoV-2 began spreading rapidly in the United States, Covid-19 vaccines were drastically cutting the number of cases. They were preventing people from being infected. And vaccinated people who got infected were unlikely to infect others.

That’s all still true, even with Delta — if just to a lesser extent.

Despite the threat of Delta, people who are vaccinated are still less likely to get Covid-19 than those who aren’t vaccinated.

But the variant appears to be causing breakthrough infections — infections in people who have been vaccinated — at higher rates than other variants, with vaccinated people also reporting higher rates of symptomatic illness. And some vaccinated people who get infected, the Centers for Disease Control and Prevention said this week, seem to carry roughly the same level of virus in their upper airways — their noses and throats — as unvaccinated people. [Continue reading…]