Micheline Leon, a woman living with HIV/AIDS, poses for a photo with her children in Cange, in central Haiti. Haitian infection rates dropped from 6.2 percent to 3.1 percent among expectant mothers in the last 15 years. Researchers recently switched to a new methodology that tests all adults, which puts Haiti’s official rate at 2.2 percent, according to UNAIDS.

Blanchard, Haiti ? When Micheline Leon was diagnosed with HIV, her parents told her they would fit her for a coffin.

Fifteen years later, she walks around her two-room concrete house on Haiti’s central plateau, watching her four children play under the plantain trees. She looks healthy, her belly amply filling a gray, secondhand T-shirt. Her three sons and one daughter were born after she was diagnosed. None has the virus.

“I’m not sick,” she explained patiently on a recent afternoon. “People call me sick, but I’m not. I’m infected.”

In many ways the 35-year-old mother’s story is Haiti’s, too. In the early 1980s, when the strange and terrifying disease showed up in the U.S. among migrants who had escaped Haiti’s dictatorship, experts thought it could wipe out a third of the country’s population.

Instead, Haiti’s HIV infection rate stayed in the single digits, then plummeted.

In a wide range of interviews with doctors, patients, public health experts and others, The Associated Press found that Haiti’s success in the face of chronic political and social turmoil came because organizations cooperated and tailored programs to the country’s specific challenges.

Much of the credit went to two pioneering nonprofit groups, Boston-based Partners in Health and Port-au-Prince’s GHESKIO, widely considered to be the world’s oldest AIDS clinic.

“The Haitian AIDS community feels like they’re out in front of everyone else on this, and pretty much they are,” said Judith Timyan, senior HIV/AIDS adviser for the U.S. Agency for International Development in Haiti. “They really do some of the best work in the world.”

Researchers say the number of sufferers was initially lessened by closing private blood banks, and statistically by high mortality rates — an untreated AIDS sufferer in Haiti lives eight fewer years than an untreated American.

Well-coordinated use of AIDS drugs, education and behavioral changes such as increased condom use have kept the disease from surging back, at least for now.

Statistics are notoriously unreliable in this country of poverty and lack of infrastructure. The most telling data would be the number of new infections in a given year, but researchers say such a precise count is impossible.

Next best is to estimate the infected as a percentage of the population. From 1993 to 2003, only pregnant women were tested, and their rate of infection dropped from 6.2 percent to 3.1 percent, according to GHESKIO and national health surveys.

Researchers now test men and women aged 15 to 49, and the official rate is 2.2 percent, according to UNAIDS.

That’s still far higher than in the developed world, but it’s lower than the Bahamas, Guyana and Suriname, and much lower than sub-Saharan Africa, where the rate averages about 5 percent but spikes to 24 percent in Botswana and 33 percent in Swaziland.

But the crisis is far from over. In the Artibonite Valley, where Boston-based Partners in Health is just now setting up two clinics, the estimated infection rate is 4.5 percent.

Some in these remote regions still look for care from Voodoo priests, who ask for large sums of money or goods and use treatments doctors say can be poisonous.

Thanks in large part to UNAIDS, which gave Haiti its first grant in 2002, and $420 million from the U.S. President’s Emergency Plan for AIDS Relief, or PEPFAR, an estimated 18,000 people are on AIDS drugs, most of them administered free through GHESKIO and PIH.

That population represents 40 percent of those whose white blood cell count is low enough for them to need the drugs. It is a high percentage for the developing world, but still fails to help many too remote to reach medical care or those at for-pay public clinics.

Still, Haiti has been sufficiently ahead in prevention, diagnosis and treatment for some of its programs to serve as models for PEPFAR, the program launched by President George W. Bush in 2003 and praised for its work in Africa.

GHESKIO co-founder Dr. Jean W. Pape was awarded the French Legion of Honor for his work, and PIH’s Paul Farmer was recently named chairman of Harvard Medical School’s global health department. In May, Haiti was honored as the host of the opening ceremony of the 2009 International AIDS Candlelight Memorial.

In a country suffering from political upheaval and natural disasters, where three-quarters of the people can neither afford nor access private clinics or fee-based public hospitals, few could have imagined at the dawn of the AIDS crisis how far Haiti would come.