As areas of the Gulf Coast remain mired in deplorable conditions, medical experts are concerned that if an outbreak of disease were to occur, the current lack of sanitation and communications would make it extremely difficult to contain.
The main worry at this point is intestinal and skin infections associated with contaminated water and food, said Dr. Herbert DuPont, former president of the Infectious Disease Society of America and a physician at St. Luke's Hospital in Houston.
Infectious diarrheas like dysentery, E.coli, shigella, bacteria, amoebas and hepatitis A all present a threat when there are sewage problems, he said. So do skin infections like staph and strep if people's scratches encounter contaminated water.
"The biggest fear is cholera, though that is very unlikely," DuPont said. "But (that) would be the most serious if it did occur … if it gets into the region, it spreads very quickly."
As standing water is a breeding ground for mosquitoes, another worry is the risk of mosquito-borne diseases, such as West Nile virus, dengue fever and malaria.
"We think it is really important for people to be keeping close track of these potential diseases," said Dr. Cynthia Sears of Johns Hopkins University, who is a member of the IDSA board. "We don't expect this right away … but it could emerge over the next few months."
The crowded living conditions of evacuees could cause acute respiratory infections, she said, while people with chronic medical problems also will be in danger following prolonged periods without medicines and treatments.
Should diseases emerge in the flooded regions, fighting them off might be a problem. "The lack of immunity is a major issue here in the U.S.," DuPont said. "Our bodies are simply not prepared to fight off all the germs that might start spreading around."
It is unclear how prepared the country is to deal with such outbreaks, Sears said. "What I see unfolding is not as swift or helpful as I had hoped. Considering the tsunami and 9/11 … we are not quite as geared up as I thought," she said, adding, "When you hear the word refugee applied to our own citizens, that is sobering and unbelievable."
The Environmental Protection Agency must regularly test the water to check for E. coli and coliform counts, which indicate there are feces in the water, DuPont said. Contaminated water can be treated with chlorine or by boiling it.
DuPont said it is crucial for communications in the region to be improved, including creating command posts to track what's happening in each hospital. "I do not know if they have anything organized at all," he said of officials in the region.
"Communication is key for controlling infectious disease from spreading," DuPont added. "For example, if you know in one clinic that cases of a certain disease are coming in, then you can isolate them and tell other clinics to be on the lookout for this problem -- then they can isolate, too.
"They all need to talk to each other to keep a grip on little outbreaks that pop up so they do not become big problems."
Amy Malick reported this story for ABC News' Medical Unit.