MARTIN ENSERINK | Science | Edited extracts
LIHIR ISLAND—In a small village 15,000 kilometers from home, Oriol Mitjà jumped out of a white van one early May afternoon and started to look at people's legs.
"Any children with ulcers here?" he asked in Tok Pisin. "Can we see them?"
Soon, a young woman pushed a crying boy about five years old toward Mitjà. The boy was barefoot; he had a mop of blond curly hair, like most kids here, and was dressed only in dirty blue shorts.
A group of villagers, mostly women and children, had gathered to watch. "What's his name?" Mitjà asked as he sat down on a low wooden bench, pulled on disposable gloves, and gestured to the sobbing kid to come sit on his right leg. "Jeremiah," his mother said.
Mitjà, 38, a physician-scientist from Spain with earnest eyes and a friendly smile, has a way of putting kids at ease. As Jeremiah calmed down and began to wipe the tears from his eyes, Mitjà took a close look at his legs.
On each, the boy had a glistening pink ulcer the size of a coin, with slightly raised edges. Nearby were whitish, warty splotches. Mitjà also checked Jeremiah's arms, hands, and the soles of his feet; they looked fine.
Jeremiah's mother didn't seem overly concerned. The ulcers were common, and she said she hadn't taken the child to a clinic. "Does Jeremiah play with the other kids?" Mitjà asked. She nodded. "Does he go to school?" No, she said—not yet.
The ulcers and splotches, or papilloma, are symptoms of a tropical skin disease called yaws, Mitjà's professional and personal obsession.
Yaws affects people in hot, humid areas in PNG and at least 13 other countries in the western Pacific, Southeast Asia, and Africa. The disease is caused by the bacterium Treponema pallidum subspecies pertenue, a close relative of the organism that causes syphilis, and it spreads primarily through skin contact, often between children.
Yaws isn't fatal, but if left untreated it can disfigure the skin and bones, causing lifelong pain and disability.
When Mitjà arrived in PNG in 2010 to work at a local clinic, he had no idea what yaws was; the disease was so neglected that it didn't appear on many lists of neglected tropical diseases.
And yet eradicating it was once a major global public health goal. In the first half of the 20th century, colonial health administrators recorded staggering numbers of cases—an estimated 50 million worldwide in 1952—in 90 countries girdling the equator.
Then, in 1948, scientists discovered that a single injection of penicillin cured yaws, and in 1952, the World Health Organisation in Geneva, Switzerland—founded four years earlier and brimming with optimism—embarked on an audacious plan to wipe it out.
But the campaign fizzled out in the 1970s and '80s. Penicillin had its drawbacks. The injections—in the buttock, with a thick, hollow needle—are painful and can introduce bloodborne pathogens if not done safely; penicillin allergy is a problem as well.
After cases had been slashed by some 95%, the campaign became a victim of its own success. Yaws faded from a global priority to a forgotten disease.
That is now changing, thanks largely to Mitjà, an assistant professor at the Barcelona Institute for Global Health in Spain.
In 2012, he published a paper in The Lancet showing that yaws can be cured with a single dose of the oral antibiotic azithromycin. That much safer and easier treatment can be given not only to infected people, but also to entire at-risk populations.
The study—"perhaps the most important [paper] on yaws in the past 50 years," as David Mabey of the London School of Hygiene & Tropical Medicine wrote—revived the dream of eradication. WHO is now spearheading a new global attack plan.
If it succeeds, it would be a major feat, because only one human disease has been eradicated: smallpox, in 1980. (Campaigns to end polio and Guinea worm disease are in their final stages.) Yaws would also be the first bacterial disease to be wiped out.
But success isn't guaranteed. The scale of the challenge is uncertain because no one knows how many yaws cases remain—or just how many countries are still afflicted. Global health's usual benefactors, having picked other priorities, have refused to open their wallets.
And some scientists say Mitjà and WHO ignore an inconvenient fact: Unlike other agents marked for eradication, the yaws bacterium—or a close relative—also infects monkeys and apes, suggesting the disease could jump back into the human population at any time.
Those questions haven't deterred Mitjà, whose tireless campaign—mixing science, medicine, and advocacy—has made him a celebrity in Catalonia, his native region of Spain.
This year, together with PNG health officials and with modest funding from a group of donors, he launched the first of three mass treatments with azithromycin, each six months apart, to test the feasibility of eradication.
Jeremiah's village on the island of New Ireland is part of the study area. "Tomorrow, a team will come with yaws medicine. Everybody will get the drug," Mitjà said after the boy, now smiling faintly, had hopped off his lap. "Jeremiah's ulcers will be gone within a few weeks," he promised the boy's mother.
In 2010, a medical centre on Lihir advertised a temporary position for a doctor. Lihir has 18,000 inhabitants and one of the world's biggest gold mines, operated by an Australian company, Newcrest Mining Limited, which also supports the clinic. Mitjà, who had finished his residency and taken a course in tropical medicine, answered the ad.
Yaws often starts with a single ulcer, which can last for months if not treated; in the second stage, lesions can turn up elsewhere on the body, as they had in Jeremiah. In the long term, the bacterium can infect joints and the outer layer of bones, causing them to swell. It also can cause painful hardening of the skin on the palms and soles of the feet, as well as eruptions on the face.
One afternoon in May, Mitjà went to see a 15-year-old Lihir boy named Stanis Malom, who had suffered long-term damage from yaws. The bacterium had caused a symptom sometimes called sabre shin, in which the shinbone curves forward. This had likely made the leg prone to tearing of the skin, Mitjà said, and caused a permanent open wound the diameter of a teacup, which he covered with a bandage.
Stanis had stopped going to school because of the pain, his father said, and was now helping him grow vegetables. (Mitjà believed the stigma of disease may also have played a role.) Stanis had been treated with antibiotics and no longer had yaws, but the damage had been done; the open wound made him vulnerable to all sorts of infections.
In a richer country, an orthopaedic surgeon might be able to repair the leg—"You'd have to break the bone and put it back together in a better position," Mitjà said—but that option did not exist here. "The bottom line is, he's not going to have a happy life."
At home, his fight against yaws had made Mitjà a star and turned pian, Catalan for yaws, into a household word. But in the wider world, the disease remained almost as unknown as it was eight years ago. "Making people aware of this disease, not only in Barcelona but also in the rest of the world," he said, "that would be my dream."