A public health emergency has been declared in South Carolina and Tennessee in the wake of Helene, according to the Department of Health and Human Services, following the same declarations in Florida, Georgia and North Carolina.

"We will do all we can to help officials in South Carolina and Tennessee respond to the health impacts of Hurricane Helene," HHS Secretary Xavier Becerra said in a statement. "We are working closely with state and local health authorities, as well as with our partners across the federal government, and stand ready to provide additional public health and medical support."

The Administration for Strategic Preparedness and Response deployed about 200 personnel to assist local officials with the storm's impacts to hospitals, nursing homes and other health care facilities, according to HHS.

The government's National Disaster Medical System has already deployed 29 trucks filled with equipment to help patients in health care facilities, many of which were totally knocked off the grid.

There have been more than 6,300 members of the National Guard mobilized to "support ongoing disaster relief, rescue, and recovery efforts in the aftermath of Hurricane Helene," according to Secretary of Defense Lloyd Austin.

There will be guardsmen from 12 different states moving into the South to help, especially in North Carolina.

"We continue to stand by the people and communities of North Carolina and all those affected," Austin added.

North Carolina Gov. Roy Cooper called the impact of Hurricane Helene on the state "absolutely catastrophic" in a statement Monday.

"This is an unprecedented response and an absolutely enormous coordinated effort by the state, federal and local partners," Cooper said.

Cooper, who inspected the staging area at the Asheville airport Monday, said "Hundreds of thousands of pounds of supplies are being flown in, packed onto helicopters and flown into areas that can't be reached by vehicles."

The Federal Emergency Management Agency (FEMA) has delivered 1 million liters of water and 600,000 meals to people in North Carolina, Cooper said.

The governor added that there are 92 search and rescue teams working to help bring residents to safety.

President Joe Biden told reporters from the Oval Office he will travel to North Carolina on Wednesday to survey the damage.

He said he plans to land in Raleigh for a briefing and then do an aerial tour of Asheville to avoid straining on-the-ground resources.

He said he will visit Georgia and Florida "as soon as possible after that."

Asked by ABC News' Karen Travers how Americans can help out, Biden recommended people reach out to the Red Cross -- and gear up for a long recovery.

"There is a lot to do, and this is just beginning," Biden said. "We've been through this before, but not -- not like this. This is the worst ever."

-ABC News' Cheyenne Haslett