By Robert Bazell, NBC's chief science and health correspondent

PORT-AU-PRINCE – The medical situation in Haiti is improving vastly almost by the minute – more hospitals, more doctors, and more relief supplies coming in. Although it's clearly too late for a lot of people who got infections from wounds that progressed too far to be saved.  

But overall, more and more people's lives are being saved and the situation has gotten much more organized. For instance, Port-au-Prince General, the public hospital and the biggest hospital in the city, has a very efficient system now.  U.S. soldiers from the 82nd Airborne are helping out. They have implemented a very orderly admissions process – a triage system – so that the sickest get treated right away. And the hospital now has at least 10 operating rooms functioning full time.  

SLIDESHOW: Haitians grapple with earthquake's aftermath

In terms of supplies, there has been some improvement in terms of distributing goods on the ground, but there is still a constant shortage of supplies. The U.S. Marines are dropping supplies at the Presidential Palace via helicopter drop and those supplies can be brought to the hospital. 

One of the many bottlenecks has been the lack of functioning vehicles and the short supply of gasoline.  As a result, getting supplies to the airport is just the first step in a long process of trying to get it to where it is needed. If water or food just gets dropped into a group of people, it can create a mini-riot. So it has to be given out in an orderly way.  The same rule applies to medical supplies.  If you can get it very close to where you want it to be, you've made the process much faster.

These hospitals are still doing an awful lot of amputations because wounds are getting gangrenous. And because of the nature of crush injuries, which break down the blood cells and can damage kidneys, a lot of people need dialysis. Some of the hospitals, as well as the USS Comfort, are beginning to have the capability to help people who need dialysis, so that's an improvement.

Making best of bad situation
But the long-term question in terms of health is that you can't untie sanitation, housing and health. They all go together in a big way. They are enormous challenges and it's not clear what's going to happen with them in the next few weeks and months.

VIDEO: Saving lives in a world of ruin

I spent a lot of time at GHESKIO, an acronym for a Haitian group who were among the first to treat AIDS here, and saw how they were making the best of a bad situation.

They immediately turned the grounds of their clinic into a shelter. Dr. Jean Pape, the doctor in charge of the clinic, said that he really had no choice because the people who lived nearby had no place to go.  He managed to get food and he couldn't get more water delivered, but he was able to throw chlorine into the water he had so he could to purify it and distribute it. By the time I saw it, the make-shift camp probably had about 10,000 people.

Pape set up a system to distribute food that wouldn't cause riots. They had hundreds of pounds of rice that they got from an aid organization, but for the first few days they were very cautious about distributing it. 

There was one guy in camp who seemed to be itching to create a riot. He seemed like an organizer, but also a rabble rouser who might cause trouble. So, the clinic co-opted him by hiring him for a small amount of money to be the organizer of the food distribution system.

Then they also identified women throughout the camp who were cooking some food already. These women were getting food because their husbands were out scrounging or had gotten food from relatives. There was not a lot of food, but they were cooking. They designated those women to cook the food for everyone – the idea being that they would have to share. So that way, suddenly, food was disbursed throughout the entire camp in an orderly way and there were no big riots.

VIDEO: USNS Comfort soothes ailing quake victims

Critical issues: Sanitation & housing
So that was the food issue, the next big issue is sanitation. Everybody is screaming for sanitation.

Someone asked Army Lt. Gen. Ken Keen, the commander of Joint Task Force Haiti, about portable toilets at the Port-au-Prince General Hospital and he said that there was not a single portable toilet in Haiti.   

But improving sanitation is high on the list of things to do. People are defecating on the ground and it's an enormous public health issue. There is almost certainly going to be a typhoid outbreak in the next week or two if something isn't done about providing better sanitation.

Then the next need is tents. These people are sleeping outside under bits of sheets or blankets. It's not the rainy season, but it could rain anytime. And you can only imagine how bad the health consequences could get if it does rain.

And right now, you have people who have successfully had a leg amputated and dressed properly, but very few of these medical facilities have any clean place where people can stay. So people go back to sleeping in these horribly, filthy situations. Inevitably, a lot of these wounds are going to get re-infected and could cause a second wave of people who will need to be treated for their wounds again. And a lot of those people may die.

It makes you wonder about what kind of shelter these people will live in. Will Haiti become a country of tent cities?

On Friday, hundreds of thousands of people crammed onto buses to flee Port-au-Prince and move to tent cities the government promised would be cleaner and safer. Others were also trying to get out to the countryside where they could stay with relatives. 

Because having a mass of people assembled in the city is a disease outbreak waiting to happen. Tuberculosis, respiratory and diarrhea-related illnesses are a constant threat.

So there has to be a long-term plan. But Haiti isn't a place where there is much of a functioning government. And I'm not sure who wants to pay for it. The world has put a generous amount of money and people towards the immediate rescue effort, but people have to start thinking long term.

Resilient people
Still, you see survival stories every day. There is a beauty about the people and parts of the country that is inspiring. The Haitian people have lived through so much misery. From the recent hurricanes, to the political situation, to the enormous AIDS outbreak and the intense poverty that they live with daily that they are very tough people.

They are able to take a lot because they've been through so much. And maybe that will end up playing to their advantage. 

In terms of survival stories, we've seen so many amazing individual stories. But they add to a collective story of people who are capable of being very wily and able to take care of themselves because they have been so poor and suffered so much, for so long. There is resilience, but you'd have to say it's been tested pretty severely.   

Click for complete coverage of the earthquake in Haiti