The following text, by Dr Gro Harlem Brundtland, Director-General of the World Health Organization, appeared today as an "Op-Ed" in the International Herald Tribune.

Outrage about the plight of those with HIV in developing countries has recently reached the pages of Western newspapers. This is good. The fact that less than a tenth of the 36 million people infected by HIV can afford the drugs used to treat the disease is outrageous.

But it isn’t a lost battle. In fact, we have begun dismantling the obstacles that are preventing essential drugs from reaching the millions who need them.

We are seeing an unprecedented effort, driven by committed people from governments, non-government organizations, UNAIDS, WHO, other UN organizations, and the private sector.

Popular outrage, political will, market forces and the best science are enabling the pursuit of a fundamental principle of public health: the supply of essential medicines on the basis of need rather than on the ability to pay. In this case, the forces of globalization are being used to narrow the gap between the wealthy and the poor.

A year ago, the medicines needed to slow the progression of AIDS were far beyond what most Africans, Latin Americans, and Asians, or their governments, can afford. At a cost of $10.000 to $15.000 per person year the drugs are out of reach, and there has been little stimulus for developing country governments to organize their health care systems to treat those living with HIV.

Today, antiretroviral combination drug therapies have become available to some African countries for around $1000 dollars per patient per year – a tenth of what they used to be. Offers last week by a pharmaceutical company producing generic drugs mean that these combination therapies could be made available in Africa for a price of $600 or less per person per year.

True, such prices are still beyond what almost any African health system and most patients are able to spend. But it must not stop here. We must ensure that not only HIV/AIDS drugs but all essential medicines and vaccines are accessible to all. It will take time, but we must make sure that no moment is wasted.

Yes, it is a difficult process. Along the road, there will be disputes about how trade agreements are to be interpreted. There will be challenges to national drug policies which threaten to change the established order of things. There will be arguments about patent rights and they can only be solved by testing their limits through a legal process. The stakes are very high indeed.

We want differential pricing to work in practice. This means appreciating companies’ concerns that lower prices in the poorest countries should not be used as a lever to influence negotiations in those which can easily afford to pay more. We need mechanisms to prevent illicit re-export of lower priced drugs into richer economies. We need an environment where the right regulations are fairly enforced so that competition can work effectively. This is starting to happen: just watch how prices of generic drugs (that are not protected by patents) are falling as rapidly as their brand-name counterparts.

We must ensure that getting the patent holder a reasonable return does not block best-price efficiencies. An effective regime for international trade is one which allows countries to implement workable systems that secure health needs while respecting intellectual property.

It would be naive, however, to think that cutting the prices of medicines is enough. Medicine costs of $600 per person per year are still beyond what almost any African health system and most patients can afford. The prospect of cheaper medicines stimulates demand for care, and this will actually increase the need for resources.

No matter how low prices go, it is inevitable that additional funding will be needed to meet the costs of care for the poorest. Developing country governments can commit their own resources, like Brazil and other countries have already shown. But most of this money must come through increased development assistance as well as debt relief. This has to be new money. We can’t take from the little that is already being spent on other common deadly diseases such as those which kill four million children each year.

Experience has shown that combination therapy can be effectively administered in Africa without the elaborate laboratory monitoring which is routine in industrialized countries. But there is concern that lack of monitoring will cause resistance of the HIV viruses to AIDS medication that quickly will render the available medicines useless. We can deal with this. We can find a safe minimum standard that ensures safe use of quality drugs while being affordable in poor countries.

Through all this, we must ensure that the new hope of wider access to care complements and strengthens efforts to prevent HIV from spreading. Keeping people free from HIV must always remain our main goal.