WASHINGTON (NEXSTAR) — Federal officials say they will send more resources to communities that are seeing a resurgence of COVID-19 to try to get more people vaccinated.

During a Thursday briefing, U.S. Centers for Disease Control and Prevention Director Rochelle Walensky pointed to “new and concerning trends,” saying hospitalizations and deaths are rising in communities with low vaccination rates. She said 99.5% of new cases are among unvaccinated Americans.

She blamed the highly transmissible delta variant. It now accounts for more than half of all cases nationwide and up to 80% in some places, including the Midwest.

“This rapid rise is troubling,” Walensky said.

The White House is now surging resources to those hot spots, partnering with local doctors and faith leaders to urge more people to get vaccinated soon.

Rep. Emanuel Cleaver, D-Mo., said he’s working a large-scale event to encourage the most hesitant Missourians in rural and Black and brown communities to get vaccinated.

“If we don’t (get more people vaccinated), we’re going to have a problem,” Cleaver said. “Our numbers are horrible. … People are dying.”

But Missouri Gov. Mike Parson said he doesn’t want government officials going door-to-door providing vaccine information in his state.

White House COVID-19 Response coordinator Jeffrey Zients said discouraging the work will cost lives.

“I believe you are doing a disservice to the country,” he said of Parson.