The World Health Organization reports that the emergence of multi-drug resistant tuberculosis (MDR-TB) has become a major global challenge.

But presidents of TB hospitals nationwide who participated at a five-day meeting in Liaoning Province earlier this month pledged to dedicate themselves the national program for TB prevention. Their goal is to bring TB under control by the end of next year.

MDR-TB is the result of the resistance that mycobacterium tuberculosis, the causative agent of TB, has developed to two of the most commonly used drugs used for treating the disease.

The China Center for Disease Control and Prevention (CDC) says that 27.8 percent of the country's 4.5 million TB patients develop MDR-TB. Bacilli that survive are drug-resistant and may be transferred to new hosts, creating a new generation that will have greater resistance.

MDR-TB is more dangerous, and fatal in most cases, because it is harder to cure. Patients must take second-line drugs, which are much more expensive and have more side effects. This often multiplies tenfold the cost of treatment.

Inappropriate or insufficient treatment and inability of many patients to pay are major reasons for the rise in MDR-TB in China, said Zheng Suhua of the National Clinical Pharmacology Research Base.

The current treatment regimen for TB involves a combination of four to five drugs given for a minimum of six months. Most patients feel better three months into the treatment and many stop taking the drugs. This leaves the disease in remission and results in the surviving bacteria evolving into drug-resistant strains.

Around 35 percent of China's TB patients live in the countryside and do not have stable incomes. The annual income of patients in rural regions is around 900 yuan (US$108), according to the latest report on TB released by the Ministry of Health.

Xiao Lei's 10-year battle with TB has cost her farming family about 50,000 yuan (US$6,000). Now that she is in Beijing being treated with second-line drugs for MDR-TB, her illness is costing about 600 yuan (US$73) per day.

More than 60 percent of patients from rural areas leave the hospital before they are fully recovered because they have no medical insurance and cannot afford to pay for the treatment.

DOTS -- Directly Observed Treatment, Short-course -- is presently the most effective regimen used to cure TB patients and prevent MDR-TB.

With DOTS, a supervisor will watch the patient swallow the tablets and continue to do so until the patient is fully recovered. Usually such a course lasts for six to eight months.

Such a therapy regimen ensures that a TB patient takes the right drugs, in the right doses, at the right intervals, for the required amount of time. Supervisors can observe patients' treatment in either inpatient or outpatient settings.

DOTS was pioneered by the International Union against TB and Lung Disease (IUTLD) and recommended by the WHO in the early 1990s. It has now been introduced in 180 countries worldwide.

In areas where DOTS has been implemented, cure rates of up to 95 percent have been recorded, even in very poor countries. Moreover, DOTS helps stop transmission of new infections and the development of MDR-TB. It has been ranked by the World Bank as one of the most cost-effective of all health intervention programs.

In April 1991, a DOTS pilot program was implemented among two million people in five Hebei Province counties. By the end of the year, the program reflected a cure rate of 94 percent. By 1995, China had expanded DOTS to nearly half the country.

World Bank records indicate that the number of TB cases detected per year increased from 835 in 1990 to over 130,000 by 1995. Since 1993, nearly 91 percent of patients starting treatment have been cured.

Early detection and early and full-course treatment are the most important elements in getting the TB epidemic under control. Because TB bacilli are transmitted through the air, it is impossible to stop the transmission channels as can be done with HIV/AIDS. Moreover, the existing TB vaccine, BCG (Bacilli Calmette-Guerin), is not completely effective.

In spite of the difficulties, such as shortages of medical workers and funding, health officials and TB control experts are all quite confident of fulfilling the global target of bringing TB under control by the end of next year. Their confidence is based on strengthened national and local policies, budgetary support and the involvement of more people from all walks of life.

(China Daily July 23, 2004)