By IPS Correspondents
NEW YORK, Feb 14 2004 (IPS)

Although powerful antibiotics have stamped out leprosy in most parts of the world, the ancient and dreaded disease maintains a foothold in a dozen countries where transmission rates remain surprisingly high.

Once banished to quarantined "colonies" or sanatoriums, the vast majority of leprosy patients now have access to free drug cocktails thanks to the World Health Organisation (WHO), and are easily cured.

But at least 700,000 new cases of leprosy are still diagnosed each year, and in the handful of developing countries hardest hit by the disease, the number is reportedly growing.

The WHO has been forced to push back its target date for the global elimination of leprosy from 2000 to 2005 – and even that deadline is starting to look doubtful.

"The great danger now is that we become complacent with the numbers affected," said Terry Vasey, chief executive of the Leprosy Relief Association, a British charity.

"We must remember that elimination of the disease as a public health problem is simply defined as one (case) in 10,000 population. This can still leave sizeable burdens in some countries such as India," he noted.

Twelve countries – Angola, Brazil, Central African Republic, Congo, Cote d’Ivoire, Guinea, India, Liberia, Madagascar, Mozambique, Nepal and Tanzania – are now coping with 90 percent of all leprosy cases, making them the focus of WHO’s five-year strategy.

But solutions are hardly simple. Experts note that most of these countries suffer from political instability, feeble health care systems, or a combination of both. Leprosy diagnosis and treatment also tend to be highly centralised, and the disease remains a source of fear and revulsion, inhibiting victims from seeking help.

"Improving the accessibility of cases to multi-drug therapy is still the main strategy," Dr. Ayodele Awe, a WHO official based in Lagos, Nigeria, told IPS.

"We need to decentralise leprosy services to the peripheral health facilities, and increase the public awareness of leprosy, especially on the early symptoms and signs," he said.

While the WHO’s "final push" elimination plan has been endorsed by all endemic countries, some non-governmental organisations (NGOs) are concerned that victory has been declared prematurely.

"The WHO always points to the prevalence of the disease and how that has fallen – which it has, and this has been a remarkable achievement by all those concerned with leprosy à when you consider it is one, if not the oldest, disease known to man and remains one of the great taboos," Vasey told IPS.

But, he added, "it is comparatively easy to say that elimination has been reached at a national level and (we) still have areas which are highly endemic".

"Almost anything can be proved with statistics, but to the person with the disease, it is as devastating today as it has always been if it remains untreated."

Other experts stress the goal has never been to "eradicate" leprosy, but to reduce the rate to less than one in 10,000 people, and argue that many newly diagnosed cases actually represent infections that have gone undetected for years.

"India has about 70 percent of the world’s reported cases – but note that it has a billion people," said Paul Fine, an epidemiologist at the London School of Hygiene and Tropical Medicine and member of the WHO’s technical advisory group on the elimination of leprosy.

"The current approach of finding and treating cases is the most reasonable we have," he added in an interview. "A vaccine is possible, but unlikely to be practicable, as the disease is so rare."

Vasey agreed, believing it unlikely that drug companies would invest in such unprofitable research.

"The drive is to keep leprosy on the agenda of health decision makers," he said. "We are all trying to assist in the process of integrating leprosy into public health services, and at times there is a natural reluctance on the part of some staff to this process."

"This is especially true when a health facility is poorly equipped, both in terms of staff and equipment, and is serving a population of 100,000 or more people," added Vasey.

Still, scientists have not given up trying to tackle the disease at the molecular level. Earlier this month, an international team of researchers announced they had discovered a genetic variation that makes some people five times more susceptible to the leprosy bacterium.

"I think for public health purposes, the findings will be most important for identifying who should be treated," said Dr. Erwin Schurr, a genetics professor at McGill University in Montreal who led the study.

The results of the team’s research appear in the February issue of the journal ‘Nature’.

"Given the effective drug treatment and the absence of a natural reservoir, it is surprising that there has been no substantial drop in the worldwide incidence over the last 10 to 12 years," Schurr added in an interview.

"Since our genetic studies suggest a two-step model of leprosy pathogenesis, an interesting hypothesis that could be tested is if people who are genetically at increased risk of leprosy – but show no clinical signs of leprosy – function as a reservoir of the disease."

While leprosy is spread through personal contact, scientists have been stymied by where the germ hides out in a dormant state – a human, plant or animal host unaffected by the disease but able to pass it to others, known as a "reservoir".

Experts believe the answer could help explain why transmission rates are holding steady, a key to wiping out the scourge for good.

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