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."
The U.S. government is also focused on providing health and humanitarian aid.
President Obama said Wednesday 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 U.S. has prepared the hospital ship the USS Comfort for possible deployment to the region.
Rajiv Shah, an administrator with the U.S. Agency for International Development, said Wednesday 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."
ABC News' Lauren Pearle and Lee Ferran contributed to this report.