Search for a Leprosy Cure - 2002-01-27

Leprosy, an ancient scourge of humanity, has largely disappeared from the industrial world. But the World Health Organization says poverty, unsanitary conditions and poor nutrition still produce some 850,000 new cases every year in Africa, Asia and South America. One of the few laboratories devoted to leprosy research is at the Florida Institute of Technology near the Kennedy Space Center in Melbourne, Florida.

India is one of the remaining hotbeds of leprosy. So it is fitting that a native of that country, Dr. Arvind Dhople, who has spent 38 years in leprosy research, is director of the laboratory. "Growing up in the city of Bombay in India, where leprosy is very prevalent, I used to see leprosy patients all over the city all the time, and with all their disfigurement, I was very curious as to what is happening to these people," he says. "And so I told my professor, I shall take leprosy for my Ph.D. research."

Leprosy is also called Hansen's disease after the 19th century Norwegian physician who isolated Mycobacterium leprae, the organism that causes the disease. The first symptom is a small abrasion on the body where the leprosy bacillus attacks the nerves. The patient loses all sensation, including pain, in the affected area. If this happens to the foot, the patient does not feel pain, keeps on walking and as a result eventually develops the deformities characteristic of leprosy.

"Leprosy is one of the few infectious diseases where the disease itself does not kill the patient but it spawns the mutilation in the patient and this is the reason why not only the patient but the patient's family members are outcast from society. So it is really not a clinical problem itself, but it is also a big social problem for these patients," says Dr. Dhople.

Even though Dr. Hansen isolated the bacillus more than 100 years ago, little is known today about leprosy, how it is spread, or why it attacks some people and not others. The organism is extremely slow to multiply and that makes it very difficult to study. "For example, if you take a common bacterium like E. Coli, which is present in our stomach, this organism multiplies from one to two every 18-20 minutes. If you take the tuberculosis organism, it multiplies every seven hours," says Dr. Dhople. "Now, if you take the leprosy organism, it multiplies every 21 days. So it is a slow-growing disease, slow-multiplying organism. One needs lots of patience to work with this organism."

However, Dr. Dhople apparently is succeeding in the development of a way to make the organisms multiply. "We have been able to get from one organism about 100 organisms. So this good progress," he says. "It is not the final answer but the way that we are moving,] we should be able to grow these organisms successfully in the laboratory. That will open the way to prepare the vaccine and eventually eradicate the disease."

Meanwhile, Dr. Dhople is evaluating various drugs that are used for other illnesses, to see whether these drugs could also work for leprosy. So far he has found two drugs that appear to be effective against leprosy. "These are now being tested, one by a Swiss pharmaceutical company in Ethiopia, and another by a Japanese pharmaceutical company in Paraguay," he says.

Nearly halfway through a 10 year testing project, the drugs seem to work on the patients. And Dr. Dhople hopes that will lead to a vaccine. "I am quite hopeful that at least in my lifetime, a vaccine will be developed for leprosy and we should be able to eradicate the disease within 20-25 years after that," he says.

Little more than 100 years ago leprosy was common in Europe, especially in the Scandinavian countries, and also in Japan. It was eradicated by prevention through improved sanitary conditions and better nutrition. Research by scientists, such as Dr. Arvind Dhople of the Florida Institute of Technology, holds out the promise that one day leprosy will disappear from the rest of the world as well.