Normally this time of year, many allergy and asthma sufferers along the Gulf Coast would be struggling to cope with the ragweed that's now in full bloom. This year, they'll likely face even more breathing difficulties in the wake of hurricane Katrina, doctors say.
And many other people may be at risk for developing respiratory problems because of the mold that's expected to flourish, particularly in flooded areas, plus the stress of enduring one of the worst natural disasters to ever hit the United States.
At the University of Mississippi Medical Center in Jackson, Dr. Gailen Marshall says he's seeing and hearing about Katrina survivors who are having allergy and asthma attacks brought on by the emotional toll of the hurricane.
"These are people who are winding up in urgent care clinics and hospitals," says Marshall, director of clinical immunology and allergy at the hospital.
Under normal circumstances, though, many of these patients say they typically would experience little more than a case of pollen-induced sniffles and perhaps some mild wheezing, he says.
Some studies, including one published last week in the Proceedings of the National Academy of Sciences, support a connection between stress and the worsening of allergies and asthma.
Compounding problems for allergy and asthma patients along the Gulf, many do not have their proper medications, Marshall says, nor do they have access to air conditioning to filter out the pollen.
Marshall also says he expects that some people who don't currently have breathing troubles could develop them down the line because of stress that weakens their immunity.
'Ideal' conditions for mold
In addition, people could become sensitized to mold, which will be widespread especially in flooded areas of New Orleans. People with compromised immunity because of disease or organ transplantation will be at particular risk.
People refusing to evacuate New Orleans could quickly face health problems because of mold growth, experts say.
The smells from polluted water also could trigger asthma symptoms, says Dr. Richard Wasserman, medical director of allergy and immunology at Medical City Children's Hospital in Dallas and a spokesperson for the American Academy of Allergy, Asthma and Immunology.
But long after the floodwaters are gone, the mold problem will persist for months, making it a risky proposition for people to eventually return to their homes, according to Wasserman.
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"Everything that is water-damaged will grow mold," he says.
And hot, humid weather will make it difficult for the area to dry out. "The conditions now are ideal" for mold to grow, Wasserman says. "The mold problems will be very significant."
Advice for returning home
Before people settle back into their homes, the buildings should be inspected by health officials and proper steps should be taken to deal with the mold, says Dr. Dorsett Smith, a respiratory specialist at the University of Washington in Seattle and a member of the disaster response committee for the American College of Chest Physicians.
Damp wallboards should be removed and the studs behind them inspected. Mold grows on the cellulose in wood, and as long as moisture remains the mold will flourish, Smith says.
"With moisture, heat and food it can survive for years," he says.
Airing out the house and spraying wood with fungicide can help, but in some cases walls will have to be completely torn down to properly get rid of the mold, experts say.
Marshall says that in severe cases of mold infestation, relying on a fungicide is "like trying to put out a fire with a squirt gun."
Covering up the mold with fresh paint and carpets is only a cosmetic solution that will worsen the problem in the long run, Smith and others say. Eventually, mold that's black, pink, reddish or brown can peek through the walls.
"The key word is 'drying,'" says Anu Dixit, a public health researcher at St. Louis University, who studied the after-effects of the Missouri floods in 1993, in which some buildings were refurbished before the mold was properly controlled. "It should be dry enough before you start putting walls and carpets back."
People who are cleaning up and are sensitive to mold should consider wearing a face mask that filters the air, Marshall says.
Smith says he's particularly worried about families living in apartment buildings where the landlord just "slaps some paint" on the walls.
"What we really are concerned about is the poor," he says. Black children, in particular, have been shown to be at higher risk of death from asthma.
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