The AIDS epidemic is once again drawing international attention as activists, researchers and policy makers gather in Thailand for the 15th world conference on AIDS. However, some health experts are drawing attention to the fact that several, much older major diseases continue to kill far more people than AIDS.

In hospitals like this one in Bangkok, staff are struggling with patients who are afflicted with AIDS, the Acquired Immune Deficiency Syndrome, but are dying of tuberculosis.

TB (tuberculosis) is a highly contagious disease of the lungs that ravaged Europe in the 19th Century. Today, it still kills an estimated two million people a year. Experts say one out of every three people in the world carries TB in latent form. In Asia, two billion people are at risk.

In addition, an estimated two million people die each year from malaria, and hundreds of millions more suffer from various forms of sleeping sickness (trypanosomiasis) and leishmaniasis - parasitic diseases spread by insects. These diseases are now on the rise and often kill people suffering from HIV/AIDS.

The director of a year-old group called the Drugs for Neglected Diseases Initiative, Bernard Pecoul, says he supports the worldwide effort against HIV/AIDS, but cautions against focusing solely on this latest affliction. "The risk is that we develop [devote] all our efforts on one disease and we don't take advantage of this improvement of the public health system to tackle the other diseases," he says.

Dr. Pecoul says that of the more than 1,400 new medicines developed in the past 25 years, only a dozen have been for tropical diseases. Most new drugs have been for afflictions common in wealthy nations, such as heart disease, cancer, obesity and cosmetic enhancement.

The World Health Organization's Director of Communicable Diseases for Asia, Jai Narain, says the neglected diseases afflict mostly people who are least able to do anything about it. "All these diseases affect particularly people in the remote areas, people who are disadvantaged, people who are vulnerable and people who are poor and from neglected parts of society."

One reason is that private drug companies are carrying out most research and development in recent years. And private companies, for commercial reasons, concentrate on drug markets in wealthy nations. Dr. Pecoul says as a result, governments and multi-lateral agencies must be pressured to devote more resources to drug research.

"We need an input from the public sector. We need the public sector to bring incentives on the table," he says. 'We need the public sector to be the leader, the driving force for research and development."

Dr. Pecoul says the struggle against AIDS could be a catalyst for the battle against neglected diseases. "AIDS should be the driving force to improve the quality of care for people suffering from all kinds of diseases because all these diseases are very connected."

Dr. Narain agrees, noting that the spread of these diseases is linked to poverty and the lack of health care facilities. "When we have enhanced resources available, we can be innovative to use those resources not only for HIV prevention and care, but also at the same to build health system capacities," she says.

Dr. Pecoul says there is some progress in the fight against neglected diseases. Trials of a new anti-malaria vaccine are to begin on humans [in July] in Thailand, and a new drug for Leishmaniasis is in the early stages of development. Unfortunately, he says, the pipeline for a new drug for sleeping sickness - which afflicts hundreds of thousands of people in Africa - is completely empty.