MIAMI (AP) — As coronavirus infections rise among young Americans, so too have deaths in a population once thought to be largely shielded from the worst of the pandemic.

It marks a sharp contrast to the elderly and frail, many living in nursing homes, who succumbed to the virus a year ago before states made seniors a priority to get inoculated first.

It’s still not clear whether the delta variant leads to more severe illness in younger people but health experts say one thing is certain: The more contagious strain is causing more cases among people age 50 and under.

Most of those who have died were unvaccinated.