HOUSTON - Glenda Oliver is feeling the strain. Since the hurricane, the 47-year-old New Orleans housekeeper has stayed in two shelters in Louisiana and is now living here in the Astrodome. She has little money and has lost contact with her stepbrother and uncle, who were last seen at the Superdome.
"I've been sick in my head since it happened," she said while waiting in line near the Astrodome to find out about housing. "My nerves are just totally gone. My stomach is in knots."
In Katrina's aftermath, there are hundreds of thousands in Oliver's shoes, struggling to cope with the disaster's emotional trauma. Some are overwhelmed by grief at the loss of loved ones; some are dealing with the stress of losing everything they had and facing an uncertain future; and some have underlying mental illness and have run out of medicine.
"They're intensely anguished," said Avrim Fishkind, who has been working 20-hour days helping people at the Astrodome. "Emergency psychiatrists have seen it all. But the level of anguish here is really, really, really intense."
Within a day, he and about 500 volunteers - psychologists, psychiatrists, nurses and medical technicians - had set up a mental health clinic in a cavernous conference hall at the Reliant Arena, next to the Astrodome. At its peak, the population inside "Astro City" approached 30,000. And every day, clinic staff have been seeing hundreds of patients in makeshift rooms separated by sheets.
Therapists have seen people with depression, anxiety, psychosis and disorientation caused by lack of food and water. Over the past few days, Fishkind, co-director of the clinic, has treated several mothers who had become so distraught they could no longer care for their children.
Annie Coe Toor, a family therapist from Los Angeles, has been counseling people on the Astrodome floor.
"There is a lot of anger because this happened to them, because they lost everything," Toor said. "They are horrified about the future; they are horrified about not seeing their loved ones again."
Dr. Kay Albrecht, a developmental psychologist who wears a badge reading, "Dr. Kay, Crisis Counselor," said hurricane survivors are frantic not just over their personal losses but over their loss of control as well.
"People are just falling apart. There's a lot of fear about where they are going to live," she said.
It might be years before the psychological toll of Hurricane Katrina can be accurately assessed. But scientists who have studied disasters ranging from the Armenian earthquake in 1988 to Hurricane Andrew four years later say the emotional effects will be both short- and long-term.
In the months and years to come, experts say, some people will likely exhibit signs of post-traumatic stress: nightmarish memories and images that can be triggered by stresses of daily life.
Robin Gurwitch, a psychologist at the University of Oklahoma Health and Science Center and a specialist in disaster-related psychological trauma, worries especially about the mental health of younger victims.
"Children are an incredibly vulnerable population after a disaster," she said. "And there are so many children involved in this."
In a study of Oklahoma City bombing victims, she found that 10 months after the event, a quarter of the children in the city still had significant emotional problems.
The chaos inside the Astrodome is particularly hard on children with autism, a disorder often characterized by an intense need for routine. Faced with upheaval, lack of sleep and constant noise, many unravel. When that happens, Fishkind tries to put them in quiet rooms. In one case, he simply held a child quietly for a half-hour, calming the boy.
Some of Katrina's victims say they are coping well but wonder whether they are merely staving off an inevitable collapse.
Tiara Brown, 17, lived in a two-story home with her mother, father, sister, brother and grandmother. When New Orleans flooded, she waded in chin-high water in search of survivors. She saw dead babies floating in the water. Later, in the convention center, she saw more corpses and heard shooting and screaming.
Now at Houston's Reliant Arena, Brown said she doesn't need counseling.
"I'm all right," she said with a touch of bravado. "It will probably catch up to me later, but I'm all right now."
It remains to be seen how those with mental problems will get treatment as they are resettled in months to come. Most cities and towns dealing with evacuees are focused on immediate needs, though some, including Houston, are working on long-term plans.
Across the region, Katrina has taxed resilience. In Slidell, La., the storm thrashed Ella Batiste's home, flooding the first floor and filling it with mud, mildew and an incredible stench. Since last week, she and her husband have been trying to clean up.
Batiste, 52, can't sleep for more than a few hours because her mind races with all she must do.