The devastating earthquake in Haiti only adds to the humanitarian crisis in a nation where 80 percent of the population lives below the poverty line. It's too soon to know just how serious the situation will become following Tuesday's 7.0 magnitude earthquake, but ABC News' senior health and medical editor Dr. Richard Besser said the rescue and recovery effort would be especially complicated and difficult.
The Caribbean nation already has "some of the worst health indicators in the world," Besser said, and has a limited ability to absorb this kind of a catastrophe. Haiti is the poorest country in the Western Hemisphere, and the population of 9 million already faces high rates of tuberculosis, HIV/AIDS, viral and respiratory disease.
According to the U.S. Agency for International Development, Haiti has the highest per capita tuberculosis burden in the Latin American and Caribbean region. After HIV/AIDS, TB is the country's greatest infectious cause of mortality.
Besser said that a hospital ship en route to the region would be one of the most important parts of the aid effort, because Haiti's health care capacity was already very limited, and one hospital was flattened in the quake.
The first priority is always search and rescue, Besser said, and the focus will be on reaching the injured and saving those who can be saved. "The initial 36 hours are critical," he said, adding that difficulty in getting rescue and recovery teams on the ground quickly is "the norm."
"Communities tend to have to take care of themselves" in the first few days, he said.
Haiti's proximity to the United States makes it easier to get help there quickly, as opposed to the long delays in getting aid across the Pacific Ocean after the 2004 Indian Ocean earthquake, which left about 23,000 dead.
The ABC News medical unit spoke to a number of recovery agencies, and Besser said all are asking, "How do we get into Haiti? How do we provide those resources? Each part of the U.S. government is rostering teams."
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U.S. Government Mobilizes Response After Haiti's Earthquake
The U.S. government is also focused on providing health and humanitarian aid.
President Obama said today that his administration would make a "swift, coordinated and aggressive effort to save lives," focusing on delivering "the humanitarian relief, food, water and medicine that Haitians will need in the coming days."
One of the urgent priorities was to mobilize more "rescue, medical equipment and emergency personnel" in the coming days.
"The USS Comfort, a hospital ship whose home port is in Baltimore, is being activated," said Martha Raddatz, ABC News senior foreign affairs correspondent. "They have to get those crews into Baltimore, load that up with supplies. … That [is] not supposed to happen until Monday. A lot of this will take time. The USAID DART teams, this is the disaster relief team, will also head down, but they don't yet know how they are going to get there. They want to get into Haiti, and again, they're trying to figure out exactly how."
Rajiv Shah, an administrator with the U.S. Agency for International Development, said that his organization has been in contact with its mission director on the ground in Haiti, and that it has "deployed an aggressive and coordinated response."
After the initial rescue period, Besser said additional health consequences from the destroyed infrastructure can emerge. Areas of the country may lose water, sanitation and access to clean food, and all of this leads to additional health problems.
"Water is critical," he said. "An adult needs at least five liters of water a day. Dirty water is better than no water at all."
According to the World Health Organization, no city in Haiti has a public sewage system, and less than half of the population has access to drinking water services.
This kind of a crisis can raise the risk of outbreaks of infectious disease, particularly because so many people are left homeless, and refugee camps pose a risk for communicable diseases. The most prevalent infectious diseases are bacterial and protozoal diarrhea, hepatitis A and E, typhoid fever, dengue fever, malaria and leptospirosis.
According to UNICEF, only about 50 percent of children in Haiti received vaccinations for diseases such as DPT (diphtheria, pertussis and tetanus), polio and measles in 2007.
But Besser noted that large outbreaks of infectious disease are relatively rare, and immediate efforts will be focused on those who can "use the care and need the assistance."
He said the Centers for Disease Control and Prevention has approximately 1,000 people available, including environmental engineers, to address water and sanitation problems, and teams to "pick up on some of the public health programs."
Besser said public fears over dead bodies during a disaster are generally unfounded.
"That's one of the biggest myths," he said. "Everyone is most concerned about dead bodies. You're more likely to get a disease from a living person than a dead body."