Health Issues After Hurricane Matthew Could Include Increased Zika

— -- As the remnants of Hurricane Matthew return to the Atlantic Ocean, millions of residents in Florida, South Carolina and North Carolina are grappling with the damage left in the wake of massive storm.

At least 22 people have died in the U.S. and at least three million coastal residents were evacuated. Flooding remains a concern in North Carolina, according to Governor Pat McCrory.

Although the skies have cleared, health experts warn that related injuries and illnesses can still occur while people start to rebuild.

"The major health effects of hurricane are injuries -- acute injuries and then injuries that are sustained during the clean-up phase," Dr. William Schaffner, an infectious disease expert at Vanderbilt University Medical Center, told ABC News. These injuries are commonly sustained as people clear debris or "cut down trees and work on restoring on what's wrong on their house."

Rainfall and debris could also intensify the ongoing Zika virus outbreak, which is spread by mosquitoes.

"The secondary issue to worry about in this particular season is that now we have standing water everywhere and standing water is a place for mosquito breeding and introduction and transmission of Zika," said Schaffner.

The storm's disruption of mosquito-control efforts in the Miami area could also provide an opportunity for the Aedes aegypties mosquito population, which spreads the Zika virus, to multiply.

For areas still grappling with flooding, standing water can be a concern, especially if sewers start to overflow. Debris and bacteria can hide in floodwaters, raising the risk of health infections for those who wade in.

Health experts advise that people in flooded areas take extra precautions.

"If you have to walk in floodwaters because you're trying to clean up your home, wear boots or closed-toe shoes," Mary Casey-Lockyear, senior associate for Disaster Health Services at National Headquarters of the American Red Cross, told ABC News. "If there is sewer water involved you can always have E.coli in there. [Wash] your hands or take a really good shower if you're in the water."

The U.S. Food and Drug Administration also advises residents to avoid food that has been in flood waters and either drink bottled water or boil water for at least one minute before drinking.

ABC News' Emily Shapiro and J.J. Gallagher contributed to this report.