SUSAN DENTZER: National Guard troops are on patrol all over New Orleans and vicinity. But even as they enforce security, they can't do much about other threats: The ones to the public health.
For starters, there's the contaminated floodwater. Already, tests have shown extremely high levels of chloroform bacteria and lead in this noxious mix of storm surge and sewage. These images show how dirty it is, but they can't convey how much it smells. Add in rotting garbage and shuttered restaurant with decaying food, and it's a veritable public health crisis. Tackling it requires a specially armed force all its own.
This building just blocks from the New Orleans flood zone was a hospital until Hurricane Katrina. Now it's being turned into a well guarded command center, for a constellation of federal, state and city agencies. They'll be monitoring and battling all the threats to the public health.
Carol Rubin is a leading expert on emergency responses following hurricanes. She and other colleagues from the Centers for Disease Control and Prevention have been assessing the health threats, and drawing up plans to overcome them.
CAROL RUBIN: Until I got here, I did not appreciate the scope of this disaster and just how much rebuilding there is to do.
SUSAN DENTZER: During the tour of a neighbor near the flood zone, she told us that the most important public health step was nearing completion, evacuating residents of New Orleans and many other flooded areas. Rubin said getting people out would protect them from a number of harms, like downed power lines, or the absence of potable water, even in the scattered parts of the city where the taps were still running.
CAROL RUBIN: The message that I want to give to the community is don't drink it, just because it's coming out of your tap doesn't mean can you drink it, because you can't.
SUSAN DENTZER: We asked Rubin about a risk that some public officials had cited, that the corpses of flood victims -- a few still floating about in the water -- posed a health risk to the living.
SUSAN DENTZER: Are the bodies really a risk?
CAROL RUBIN: Actually no. They really do not pose a public health risk.
SUSAN DENTZER: In fact, scientists have learned that when a person dies, the body cools, and loses fluids. As that occurs, the bacteria and viruses present in it die as well.
CAROL RUBIN: There are certain steps that people who are recovering the bodies should take in terms of personal protective equipment. But the people that are doing that are very well aware of those steps that they should take.
ALI KHAN: (talking to people) How are you and what are you doing here?
SUSAN DENTZER: Rubin's CDC colleague, Ali Khan, is a captain in the U.S. Public Health Service and an infectious disease specialist.
SUSAN DENTZER: How worried are you, how worried should the public be about a major infectious disease outbreak?
ALI KHAN: We're very fortunate that despite the concern of major infectious disease outbreaks, they're not very common after these types of disasters, so that's fortunate. Based on our experience with previous disasters, we have recommendations in place, such as immunization recommendations.
SUSAN DENTZER: Specifically Khan told us, that means making sure all rescue workers and others operating in the area get shots for tetanus and hepatitis.
Today military planes sprayed pesticides to control mosquitoes, and avert spread of potentially deadly diseases like West Nile Virus.
Meanwhile, Rubin and Khan have begun touring hospitals in and around New Orleans, to see how long it will take to get the local healthcare system fully back up and running. They started last week at the well-known Ochsner Clinic Foundation Hospital in Jefferson Parish.
PERSON ON PHONE: We have a patient that was evacuated from her house today, obviously not voluntarily.
SUSAN DENTZER: It's one of only three area hospitals that remained open after the hurricane and flooding.
Dr. Frances Smith is an Ochsner emergency department physician. Like most of the other workers here, she's been living in the hospital since Katrina hit. She described the patients who've been coming in since the storm.
DR. FRANCES SMITH: People with infections, from being contaminated with the water; people with dehydration, or heat exposure illnesses or heat cramps related to the heat; and a large number of patients who have chronic medical conditions who have not had access to their physician or their medications.
SUSAN DENTZER: Thirteen other hospitals and many smaller clinics in the region are still closed. And some have suffered serious damage.
ALI KHAN: We're working with the city and state health department to try to figure out how to reestablish public health here. As you look around in many of these sites, that infrastructure is really gone, and many of the employees here obviously also lost their homes and also gone.
SPOKESPERSON: The hospitals are so ready to rebuild and they want public health to be not just as good as it was before, they want it to be the best ever, and this can be an opportunity to do that.
SUSAN DENTZER: And an opportunity, she says, to reap at least some benefit for New Orleans and the rest of the stricken region.