Drop in World TB Rates Ascribed to New Regimen

World tuberculosis rates have leveled off for the first time in decades because of a new treatment approach that smacks of Big Brother but has proved remarkably effective in curing the disease, World Health Organization officials said here Wednesday.

The treatment, known by the acronym DOTS (for directly observed treatment short-course), uses inexpensive, readily available drugs. Its success is based on the participation of health workers and volunteers who visit patients each day for six months or longer to ensure that they take the drugs.

Recent field studies, WHO officials said, have shown that the strategy can be used in developing and industrialized countries alike and can produce cure rates of 85% or higher. The study also concluded that aggressive treatment could cut the number of new TB cases in half within a decade.

Widespread use of the treatment “could be the single most important development in the fight against humanity’s oldest and most deadly disease since Robert Koch discovered the TB bacillus in 1882,” said Dr. Arata Kochi, director of WHO’s global tuberculosis program. Aggressive implementation of DOTS could prevent 10 million deaths in the next 10 years, Kochi said.

“We knew that [this approach] worked, but we were really surprised to see that . . . it worked this well,” said Dr. Richard Bumgarner, deputy director of the program.

But the WHO officials also cautioned that economic and political resistance to the DOTS approach in the countries of the former Soviet Union have placed that region on the brink of an explosion in TB cases and deaths. Since the collapse of communism in 1991, Russia has seen a 70% rise in TB cases and a 99% rise in TB deaths, Bumgarner said.

“No other country has experienced such a skyrocketing increase,” he said.

Health authorities are concerned about TB in Russia and in more remote countries because the disease is highly contagious and is readily carried from one nation to another by travelers. About two-thirds of the new cases of TB in the United States each year are found among immigrants and tourists.

WHO estimates that about 8 million people worldwide become sick with tuberculosis each year, with 3 million dying. It is estimated that more people are dying of TB now than at the epidemic’s previous height at the beginning of this century, when it killed nearly one out of every seven Americans and Europeans.

The disease, caused by a bacterium called Mycobacterium tuberculosis, is characterized by fatigue, loss of appetite, night sweats and a hacking cough that spreads the bacterium to others.

The bacterium can be killed by a mixture of four common antibiotics, but the drugs must be given daily for six to eight months to eradicate all traces of the germ. If the patient stops taking the drugs prematurely, a drug-resistant strain of the bacterium can emerge. Disease from these strains is much more difficult to treat and almost impossible to cure.

WHO estimates that as many as 50 million people worldwide now harbor such resistant strains.

Left to their own devices, Kochi said, most patients do not finish their therapy. They begin feeling better after a couple of months, decide they are cured and quit taking the drugs, only to land in the hospital a few weeks later with a worse case of TB.

DOTS was developed several years ago in an effort to circumvent patients’ lackadaisical drug use. It uses a system of trained health workers, as well as shopkeepers, teachers, family members and former TB patients, who visit patients each day and watch them swallow the medications.

Forced hospitalization and other forms of persuasion may be used for patients who refuse to take the drugs, Bumgarner said. The drugs themselves are relatively inexpensive, totaling no more than $100 for a complete course of treatment.

In the United States, there were 22,860 cases of TB in 1995, the most recent year for which figures are available, said Dr. Carl Schieffelbein of the Centers for Disease Control and Prevention. That agency plans its own news conference next Monday to release new incidence figures and to document the success of DOTS in this country.

One of the successful field trials cited in Berlin was conducted in New York City, which has the highest incidence of TB in the United States, with more than 3,000 new cases per year. DOTS also was used in about 43% of the 1,375 new cases in Los Angeles last year, with a high success rate, said Dr. Paul T. Davidson, director of TB control for Los Angeles County. Primary recipients of the program were the homeless and others who were less likely than others to take the pills on their own.

“Epidemiological projections [from those field tests] indicate that if only seven out of 10 existing TB patients are treated with the DOTS strategy, not only will they be cured, but the annual number of new TB cases will drop remarkably within a decade,” from 8 million a year to 4 million, Kochi said.

“Without the use of DOTS, the TB epidemic is projected to increase to nearly 9 million annual cases by 2005,” Kochi said.

Walsh reported from Berlin and Maugh from Los Angeles