The difference between AIDS-HIV as a prologue to death or a manageable chronic disease is about $8 billion a year, according to Kofi Annan, the secretary-general of the United Nations. At a special session of the U.N.’s general assembly Monday, he properly urged the developed world to stop merely talking about the problem and start a fund that would deliver needed prevention, care and medicine to combat AIDS and other infectious diseases, such as malaria and tuberculosis.

Secretary of State Colin Powell struck the right note for the United States, pointing out that the nation had spent a lot over the last two decades, particularly in research, and intended to spend more than the initial $200 million the Bush administration had pledged to Mr. Annan’s fund. The further action Monday by the United States to drop its complaint before the World Trade Organization against Brazil’s production of low-cost anti-retroviral medicines is evidence that the U.S. interest in combating AIDS worldwide is sincere. Pharmaceutical companies had accused Brazil of violating patent protections, but the United States now says the dispute can be settled out of court without endangering the cheap availability of these drugs.

AIDS cannot be just like any other infectious disease as long as it carries the social and political stigma as a “gay disease,” but it must be treated as aggressively as international efforts have treated previous scourges. The risk of not doing so is apparent in the numbers that have been repeated often in recent years: 22 million people have died from it, 36 million people have AIDS-HIV, another 15,000 a day acquire it. It is now spreading quickly through Eastern Europe and Asia.

Secretary Powell’s speech – “I know of no enemy in war more insidious or vicious than AIDS” – will reassure nations looking for help that they can count on the United States. But it was the comments of Clare Short, British secretary of state for international development, that may have best reflected the mood of both UN officials and the organizations that want it to do more to fight AIDS. Ms. Short observed, “There have been enough conferences and declarations. What we need now is urgent and much more effective action on a much wider scale to prevent the terrible suffering, loss of life and costs to development that this terrible disease is inflicting across the world.”

Mr. Annan’s fund needs neither conferences nor declarations. It needs money to help stop these infectious diseases that ruin nations. The United States over the years has made large contributions to this fight, but it can and should do much more this time.