As the floodwaters left behind by Hurricane Ike recede, residents of Galveston, Texas, and other areas affected by the storm will likely return home. But for many, an unwelcome visitor will await: mold.
And if the aftermath of Katrina is any indication, this mold will likely leave some gasping for air and others with a new allergy to contend with.
"There's going to be lots and lots of mold," said Harriet Burge, a former professor at Harvard University and the University of Michigan who now serves as director of aerobiology for EMLab P&K, an indoor air quality testing facility.
"Based on the New Orleans experience, houses were filled with water and the water sat there for so long that parts that weren't wet became moldy," owing to the condensation and humidity of the air, she said.
And that mold created a problem for people with asthma and mold allergies.
"The airborne mold levels in those places were very high because of the places that were moldy," Burge said.
While some suffer from mold allergies, many more people suffer from asthma, the symptoms of which can be set off by mold spores.
"[Mold] is a trigger to asthma. Airways narrow, and then you have a shortage of breath," Dr. Maureen Lichtveld said.
Lichtveld, who chairs the department of environmental health sciences at the Tulane University School of Public Health and Tropical Medicine, has served as the primary investigator of HEAL (Head-off Environmental Asthma in Louisiana), which looks at childhood asthma in post-Katrina New Orleans.
She said that, following a storm like this, many asthmatic children face the dual problem of a lack of medical care due to the storm and a lack of care because they come from poor families.
"In Katrina, the clinical evaluation that we are conducting ... was, for many of the children, the first access to clinical care they had post the storm," Lichtveld said.
As part of her study, Lichtveld is looking at the four or five most prevalent of 72 species of mold and their effects, but she noted that people should not waste time considering whether the mold in their homes is harmful.
"The general advice from the public health perspective is if there's mold in your home, remove it," she said.
Burge noted that some non-asthmatics may develop a new problem after Ike.
"Adults can develop allergies to mold, and that's likely to happen in this case," she said.
Some of the mistakes made by people returning to New Orleans after Katrina can be avoided after Ike, experts said.
Following Katrina, some families returned to their homes, living in one part of the home while other parts that were infected with mold were still being renovated.
"If you have mold in part of your house, you have mold spores everywhere," said Burge.
"I wouldn't recommend living in a house and sleeping in a house, where, for example, there was mold on the first floor."
Burge said that people worried about becoming ill may want to wait a while before returning, although she noted that that would be a personal decision.
However, she said people in the affected areas were likely to be resilient about their condition, given the generally humid climate.
"It must be difficult for asthmatics to live in Galveston anyway," said Burge.
But for those hoping to return, she said it can be done.
"You can actually remove mold -- you can get rid of it," she said.
"Know first what you're doing before you start cleaning up," Lichtveld said. "In the process of stripping and getting rid of carpet, those who are doing it are exposed, and so it's very important to have personal protective equipment.
"The important thing is to aerate the building as best as possible and as quickly as possible."
Lichtveld said that a chlorine solution could effectively kill mold, but for a bigger job, homeowners should consult a professional.
Also, cleaning should only be done on surfaces that can't be discarded.
"It's much better to get rid of the material affected with it than to get rid of it," said Lichtveld.
Lichtveld stressed that three precautions needed to be taken as people return to the areas affected by Hurricane Ike.
She said people with asthma should not be exposed to the mold, people who were cleaning mold needed proper protection, such as masks and gloves, and people with asthma, especially children, need to stay on their medications.
"There is no need to panic," Lichtveld said. "There is an absolute need, though, for very clear and concise communication of the risk."