The World Health Organization (WHO) reports a substantial decrease fall in tuberculosis cases in China since the introduction of the TB control strategy known as DOTS.

The World Health Organization reports China and India together account for 40 percent of the world's eight million cases of tuberculosis. It says both countries have made good progress in trying to bring down the high rates of infection.

WHO Epidemiologist, Brian Williams says a recent analysis of a tuberculosis control program China started a decade ago shows good results. He says half of the country's population followed the so-called DOTS strategy and the other half did not. He says there was a 30 percent reduction in the number of TB cases among the group, which followed DOTS.

"It shows an extraordinarily impressive result for China," he said. "The U.N. millennium goal is to reduce the prevalence of TB by 50 percent by 2015. Then clearly, if China continues as they are and extends their DOTS program to the rest of the country and strengthens it further, then they will certainly reach the millennium development goal. I am very happy to report that I think the situation is just as good in India."

If properly followed, Dr. Williams says the DOTS program can be just as effective in other countries.

The World Health Organization says tuberculosis is steadily declining in most parts of the world. Exceptions are sub-Saharan Africa and countries of the former Soviet Union. Dr. Williams says HIV is driving the tuberculosis epidemic in Africa.

"If you are HIV-positive, your risk of getting TB is about 10 times greater than if you are not," he explained. "So, if you have HIV, you are at much greater risk of TB. And, the reason it does this is that you get many more new cases of TB when there is a lot of HIV around. But, if you have got HIV and TB, you either die very quickly or you present and get treated very quickly."

Unlike Africa, Dr. Williams says there is little linkage between tuberculosis and HIV in countries of the former Soviet Union. He says the disease is mainly spreading there because of ineffective TB control services. He says drug resistance to tuberculosis is growing because patients are not taking their medicine properly.