Robert Bazell, NBC News' chief science correspondent, responds to questions about the health risks in the region and how people can protect themselves.
What kinds of specific health risks does the sewage and lead in the flood waters pose?
The sewage poses the risk of getting gastro-intestinal illness that causes vomiting and diarrhea.
Early on (in the hurricane disaster), the Secretary of Health and Human Services, Mike Leavitt, said that there was a risk of cholera and typhoid. But, in fact there is not. That is a misstatement that has been subsequently corrected by the Department of Health and Human Services.
There is no cholera or typhoid in the United States. So, even when sewage spreads, as it is in New Orleans, there is no risk of (cholera or typhoid), because the bacteria has to be there.
The major organism that is in the water is E. coli, which is a very common intestinal bacteria. Ingesting it can cause dysentery or gastroenteritis, which can be severe if it is not treated and someone gets dehydrated. But if people are properly treated and given a lot of fluids, it is usually a limited illness.
In terms of the lead or the oil and other toxic chemicals in the water, unless someone ingests a massive amount, the danger there is more of a long-term risk of cancer and other diseases having an increased risk.
That risk is a very difficult thing to quantify. You just don’t know down the line how many extra cases of cancer or other diseases there are going to be because of exposure to those compounds.
It is an unprecedented situation, of course, in many ways. But one of the unprecedented things is that there are going to be long-term side effects that no one can really predict at the moment.
What about the drinking water?
There is a huge awareness of the dangers of drinking water ... and I think most people in the region have gotten that message. There has been an enormous amount of distribution of bottled water throughout the area.
Of course, a lot of people still take showers from water systems that may be contaminated with sewage. So, you see these people in the emergency rooms. There is not a huge amount of it, but there are people constantly coming in who do have gastroenteritis. Often they are not drinking the water, but they are taking a shower and they are not careful about water splashing into their mouth or they are not washing their hands enough.
Those are things you need to be hyper-aware of in these situations. That message is certainly out there among all the people working in New Orleans. You have to obsessively wash your hands with soap and water or use an anti-bacterial cleaner of some kind.
It sounds silly, but it’s the single most important thing that anyone who is around this water can do to protect themselves from any of these risks. Wash your hands constantly.
What precautions should rescue workers operating in the flood zones take to protect themselves?
Everybody should have a tetanus shot in case they step on something. The military certainly requires that and most people have it.
If you are working in this area and you haven’t had a tetanus shot within the last two years, you should get one. They are widely available at all the medical centers that have been set up throughout the hurricane zone
Another thing is that since the New Orleans water is contaminated with fecal material, there is a risk of Hepatitis A. There is a vaccine for that and it is widely available as well.
What are some of the most common injuries and illnesses that you’ve seen?
I’ve gone into a lot of clinics, hospitals, and FEMA emergency clinics. The initial injuries from the storm have mostly been treated.
What you have now is a lot of people are injuring themselves while they are trying to do repairs to their homes. They step on a nail or something will fall on their head. That’s pretty much the most common thing.
What sort of disease-tracking efforts are being implemented?
We’ve been talking about water, but the biggest fear is the crowding at these shelters. There is a massive surveillance under way to see if there is any evidence of an unusual outbreak at one of these shelters where so many people are living in such close quarters.
There is a fear of a viral infection or something like the Norwalk virus spreading.
Hopefully people won’t be in these shelters for too long because they are really making an effort to get people out of there. But if people are living in those kinds of conditions and kids start going back to school, and then it becomes cold and flu season, some viral infection could sweep through those shelters instantly.
That is the big concern. We all talk about the water because the water in New Orleans is a dramatic story. But, in fact, the big story is the fear of a virus spreading among people rapidly in these shelters.
What methods are being used in terms of disease-tracking?
The methods of disease tracking are that teams, composed from state health departments and officials from the CDC, go daily to every medical facility that they know of and they check the medical records to see if there is any evidence of any kind of outbreak.
Disease surveillance is really key here, because you need to monitor what’s going on at all times. Obviously things can get out of hand, but so far there is no evidence of anything getting out of hand.
There have been four deaths reported that were attributed to Vibrio vulnificus, a common marine bacteria. But that is not a big cause for concern. Four deaths are of course serious, but that bacteria lives in sea water.
Most of those people were probably exposed with open cuts during the storm surge, so that is not a New Orleans issue or a problem with drinking water.
If they have any evidence of someone getting something infectious in any of these shelters, they now have the ability to send things to laboratories. There are laboratories on the Navy ships that are off shore, in the state health departments, and the CDC has people in the area as well.
So, it is very important to know what people have all the time, so that if there is an unusual spike in something, it can be dealt with.
What are the biggest health concerns moving forward?
The shelters, the shelters, the shelters. But also the other concerns would be contaminated water, as well as contaminated food.
What are the top two or three steps people can take to protect themselves now and in the weeks ahead?
Number one: Be scrupulous about getting clean drinking water. It should be available everywhere by now.
Number two: Wash your hands all the time.
Number three: If you do get sick, go to a clinic, especially if you are vomiting or have diarrhea or a fever. It can happen at any time, but if it happens during this period, go to a clinic and get medical attention. You want to make sure that you don’t have anything terribly serious or something that can spread. Don’t be a hero, go get medical care.