HOUSTON (AP) - The muddy floodwaters now soaking through dry wall, carpeting, mattresses and furniture in Houston will pose a massive cleanup challenge with potential public health consequences.
It's not known yet what kinds or how much sewage, chemicals and waterborne germs are mixed in the water. For now, health officials are more concerned about drownings, carbon monoxide poisoning from generators and hygiene at shelters. In the months and years to come, their worries will turn to the effects of trauma from Hurricane Harvey on mental health.
At a shelter set up inside Houston's George R. Brown Convention Center, Dr. David Persse is building a clinic of doctors and nurses and trying to prevent the spread of viruses or having to send people to hospitals already stretched thin.
"This is rapidly evolving," said Persse, Houston Director of Emergency Medical Services. "I always worry in these large congregations of people about viral outbreaks that cause nausea, vomiting and diarrhea. And we are just getting started."
Medics have been at the convention center since it started taking in evacuees, along with police and other first responders. Over the last 24 hours, doctors and nurses arrived at the convention center to volunteer.
- FEMA insurance chief: Harvey losses could top $11 billion
- Harvey's flooding blamed in major gasoline spill in Texas
- Harvey and Irma to slow U.S. economy but rebound should follow
- U.S. House to vote on $7.9 billion Harvey relief bill
- Immigrants are sought for labor shortage in Harvey recovery
- Shelter dogs displaced by Hurricane Harvey arrive in Chattanooga [photos]
- Mnuchin: Congress must tie Harvey aid to raising debt limit
- Harvey's floodwaters mix a foul brew of sewage, chemicals
- Houston's homeless shrug off riding out Harvey on streets
- As Harvey finally fizzles, a look at what made it so nasty
- 3 tornadoes in Tennessee blamed on Harvey
- Upbeat Trump pitches in at shelter for Harvey victims
- Trump asks for $7.9 billion down payment for Harvey relief
- As floodwaters recede, Houston officials look to recovery [photos, interactives]
- 'Don't touch me. I'm dying.' Harrowing Harvey stories emerge [photos, interactives]
- Local animal shelters open doors for furry flood victims from Texas, Louisiana
- Likely tornado damages homes as Harvey hits Deep South [photos, interactives]
- Gas prices rise after Harvey reduces flow from refineries, pipeline [photos, interactives]
- Forecasters predict sunny Labor Day after Harvey's remnants blow through
- Grim reality in the aftermath of Hurricane Harvey: More dead [photos, interactives]
- Harvey horror: Shivering girl, 3, clinging to her drowned mom
- Team made up of local emergency responders heads to Houston
- Texas chemical plant poised to explode amid Harvey flood
- Floodwaters drop across much of Houston; death toll at 20
- Western Louisiana in crosshairs as Harvey moves back to land [photos, interactives]
- Forecast brings hope as new shelters open, death toll rises [photos]
- Trump reassures those in Harvey's path that he will help [photos]
- Here are some ways to help victims of Hurricane Harvey
- Bracing for Harvey's return, worry renews: Is worst to come? [photos, interactives]
- Sohn: What lessons will we learn from Harvey?
- Chattanooga medical teams, volunteers aid Hurricane Harvey relief efforts
- More rain, more deaths: Harvey floods keeps Houston paralyzed
- Harvey slams region's economy, with damages in the billions
- Trump issues emergency declaration for Harvey in Louisiana
- Tennessee organization starts Harvey relief fund
- Desperate Harvey victims turn to social media to get rescued
- $3 billion disaster balance enough for immediate Harvey response
- A Houston family endured Harvey until the house was swamped
- Scientists say Harvey may be the soggy sign of future storms
- Residents in photo of flooded nursing home are 'doing fine'
- Photo of mother and baby's rescue becomes symbol of storm
- Public health dangers loom in Harvey-hit areas
- Officials act to protect downtown Houston from Harvey floods
- Harvey dilemma: Stay as water rises or risk flooded roads?
- Harvey spins deeper inland; full scope of damage is unknown
- Hurricane Harvey closes key oil, gas operations in Texas
- Houston roads start to flood as Harvey stalls
- Expert: Harvey weakened fast, but destruction just beginning
- Fearsome Hurricane Harvey slams into Texas Gulf Coast
- Menacing Harvey knocking on Texas coast as Category 4 storm
- Texas prepares as Harvey strengthens to Category 2 storm [interactive]
- Sandbags, plywood, generators: Texas coast braces for Harvey
Fewer than 20 people have been hospitalized so far from the convention center.
"One of our goals is to appropriately treat people here with minor things so we don't send everybody off to the hospital," Persse.
Many of the around 3,000 people who fled from Harvey's flooding waited hours in water mixed with sewage, oil and gasoline. Some weren't able to grab their medications or medical devices. Police officers on Monday afternoon were looking for more wheelchairs.
Donors have brought diapers, baby formula and other basic necessities to the convention center. Officials are working with local pharmacies to replace lost medicines and dialysis clinics to serve patients in need of treatment. The Red Cross is arranging to bring in portable showers. A shipment of 50 wheelchairs was on the way Monday afternoon.
The U.S. Environmental Protection Agency will begin sampling the floodwaters as soon as possible, said EPA spokeswoman Liz Bowman in an email Monday. EPA teams will also be visiting water and sewage plants to offer help, she said.
EPA helped secure Superfund pollution cleanup sites last week ahead of the storm and is continuing to check with site operators.
Floodwater can be dangerous for people with open wounds, particularly if they have other health conditions. After Hurricane Katrina, five people with infected wounds died and health officials believe that exposure to brackish floodwater contributed to the deaths.
Katrina taught other lessons.
"In Katrina, a lot of people were concerned about illnesses from contact with the floodwater, but more infectious disease was associated with poor hygiene in overcrowded shelter facilities," said Karen Levy, associate professor of environmental health at Emory University in Atlanta.
At Houston-area shelters, access to clean water or hand sanitizer and proper disposal of human waste should be stressed, she said.
Any health problems will be more dangerous for the most vulnerable - people with immune disorders, the elderly and the poor, Levy said.
Katrina left a wake of post-traumatic stress disorder and depression, said Dr. Pierre Buekens, dean of Tulane University's School of Public Health and Tropical Medicine. He said their surveys showed roughly 10 percent had PTSD, but also that people were resilient.
"I'm sure this will happen in Houston," he said.
The most common flood-related deaths occur when people try to drive through flooded areas, according to the Centers for Disease Control and Prevention. Carbon monoxide may kill more as people return to homes without electricity and hook up generators, said the CDC's Renee Funk.
"Any sort of roof over a generator is actually a problem," Funk said. "When people go in and out to refill the generator they can be overcome. If a structure is attached to the house, the house can fill with fumes.
Best advice: Use a battery-operated carbon monoxide detector in the house if you're using a generator for power, she said.
Mold is also a health hazard. The CDC recommends removing and disposing of drywall and insulation that was tainted by floodwater or sewage. Mattresses, pillows, carpeting - even stuffed toys - should be tossed out. Hard surfaces can be disinfected with a solution of one cup of bleach to five gallons of water.
"That little spot of mold can grow in the home especially in the heat of the South," said Dr. Parham Jaberi of the Louisiana Department of Health.
If mold covers more than 100 square feet, a trained mold remover is recommended, he said.