MIREBALAIS, Haiti — The family from a nearby village arrived at the small hospital here vomiting and with uncontrollable diarrhea, at first glance maybe a typical case of consuming bad food or water.

The New York Times

The mission in Mirebalais has had no cholera deaths in 2011.

But the fluid loss was tremendous and unstoppable; two of the three brothers were already near death, and within hours the entire family would be dead. Meanwhile, a nightmarish stream of patients filled the small reception room, as doctors and nurses scrambled to rehydrate them.

It was the evening of Oct. 15, 2010. Cholera, the doctors with the Cuban medical mission that treat most of the patients here would soon confirm, had arrived in Haiti.

“We went back to our books to see if this really could be cholera and then reported it right away,” said Dr. Jorge Luis Quiñones, a member of the Cuban medical mission here at the center of the outbreak.

More than a year later, cholera has killed 6,600 people and sickened more than 476,000 — nearly 5 percent of the nation’s 10 million people — in what United Nations officials call the world’s highest rate of cholera. Last month, Partners in Health, a nongovernmental organization, announced it would begin testing a vaccine in January, in conjunction with the Ministry of Health and a Haitian health organization.

As the epidemic continues, the Cuban medical mission that played an important role in detecting it presses on in Haiti, winning accolades from donors and diplomats for staying on the front lines and undertaking a broader effort to remake this country’s shattered health care system.

Paul Farmer, the United Nations deputy special envoy to Haiti and a founder of Partners in Health, which has worked extensively on health care in Haiti, said the Cubans sounded an important early alarm about the outbreak, helping to mobilize health officials and lessen the death toll.

Even more, while the death rate peaked last December and the world’s attention has largely moved on, “Half of the NGOs are already gone, and the Cubans are still there,” he said, using the abbreviation for nongovernment organizations.

Cuban doctors have worked in Haiti since 1998, when 100 arrived after a hurricane as part of Cuba’s five-decade program of establishing international medical missions. Since then, Cuba has worked with Haiti and Venezuela and lately Brazil, Norway and other countries to build and provide staff and equipment for several dozen small community hospitals, clinics and other treatment centers.

The Cubans have sent doctors abroad since the 1960s as a form of “medical diplomacy” that brings badly needed doctors to remote areas of poor countries, mainly in Africa, as well as to allied countries like Venezuela, while sowing international solidarity, said Katrin Hansing, a Baruch College professor who is writing a book on Cuban overseas aid.

“It gives them a lot of political capital in the developing world, to keep up that heroic image of Cuba against the United States, that despite the embargo they still champion help to less-developed countries,” she said.

It has also been an important source of foreign currency for Cuba, with earnings from the export of medical services, including 37,000 health workers overseas, estimated at more than $2 billion. Ms. Hansing said that these days the Cubans typically ask host countries to pay a sliding scale that averages $2,500 per doctor, per month. But Haiti, she said, is one of a few countries that are not charged.

There is no doubt that the Cuban mission has been vital here. It was among the largest international aid contingents to respond after the January 2010 earthquake that tumbled Haiti into crisis. And since the cholera outbreak, the mission has treated more than 76,000 cases of the disease, with just 272 fatalities — a much lower ratio, at 0.36 percent, than the average across Haiti as a whole, in which 1.4 percent of cases ended in death, according to the Health Ministry.

“We work a lot on the education of the population,” said Dr. Lorenzo Somarriba, the chief of the Cuban medical mission. “We send people to the homes of the victims and educate them on the disease and provide them with tabs to clean the water. This is absolutely vital.” Such purification tablets have been critical in a country where treated water is rare.

Indeed, here in Mirebalais the team has not seen a fatal cholera case since December, he said.

It is a success the Cubans eagerly promote, with Fidel Castro issuing several “reflections,” personal commentaries that appear in state-run media and Web sites, chronicling the group’s endeavors and achievements.

For the doctors at the heart of it, the salaries are meager by American standards, roughly $500 per month, Ms. Hansing said. But they do not pay room and board abroad, and they get to travel the world — a perk few Cubans are allowed — and usually get to import goods from the countries they visit tax-free.

They are not allowed to bring their families with them, but the other incentives make it “a pretty good deal,” she said, that has helped keep down defections. Still, a program the United States has run since 2006 that is tailored to attract Cuban medical professionals abroad has enticed several hundred to defect.

Several of the doctors, many of them recent medical school graduates, said they simply relished the chance to practice what they had only heard about from textbooks and take on big responsibilities they would have to wait years for at home.

“We knew cholera from school, but it was hard to believe and see it here because Haiti didn’t have it before,” said Dr. Robert Pardo Guibert, 29, who directs a clinic in nearby Hinche. “But it is amazing because we treat everything here, every day there are different kinds of cases.”

Dr. Quiñones has traveled to Venezuela and Pakistan and, though he misses his family — he is not due to return to Cuba until May — the recognition from the Haitians helps sustain him emotionally. “The simple cases are the most gratifying,” he said.

The Haitians under treatment here, just grateful to have doctors, do not seem to care what nationality the physicians are.

“They provide good service,” said Mercidieu Desire, 33, who was being treated for diarrhea that doctors concluded was not cholera. “I came in, they treated me and I feel better.”

Still, the geopolitical theme of David vs. Goliath that permeates almost everything involving Cuban foreign affairs is present in this effort, as well.

After Hurricane Katrina, the Cubans offered to send 1,500 doctors to the United States. When there was no reply, Mr. Castro publicly lamented being spurned and created the Henry Reeve medical brigade, named after an American doctor who fought for Cuba’s independence, that would assist in natural disasters around the world.

In Haiti, the Cubans have asked the United States to help finance a $30 million major hospital for specialists that would be staffed in part by Cuban doctors as part of the broader effort that Cuba and other nations have undertaken to remake the health system here. But after intense rounds of talks — with both sides claiming last-minute changes to the arrangement — no deal has emerged.

“Recovery in Haiti is a broad international effort, and we have been in touch with many other governments, including Cuba, to advance health sector support to Haiti, but we have not entered into any agreements with the Cubans,” Jon E. Piechowski, a spokesman for the American Embassy, said in a statement.

Copyright 2011 The New York Times Company. Reprinted from The New York Times, International, of Tuesday, November 8, 2011.