he AIDS epidemic is a humanitarian catastrophe. But as the virus spreads insidiously around the world, it is becoming something else — a threat to global and regional stability, because of its potential to disrupt the economic, political and military structures of key countries.

Until now the main impact of AIDS has been in central and southern Africa. Now a report from the National Intelligence Council, which prepares analyses for the American intelligence community, provides alarming estimates of the next big wave of AIDS infections. It says they will soon hit Nigeria, Ethiopia, Russia, India and China, countries with more than 40 percent of the world's population. All are regional or global powers.

The number of infected people in these countries is projected to triple over the next eight years, reaching roughly 50 million to 75 million in 2010. Nigeria and Ethiopia could be devastated, losing a big slice of government and business professionals and suffering a loss in economic growth and foreign investment. Their ability to play regional leadership roles could be seriously weakened. In Russia, AIDS could exacerbate the severe health problems and population decline, slow economic growth and weaken the military, which already loses a third of its prospective conscripts because of H.I.V. or hepatitis infections caused by drug use. China and India, though projected to have the largest number of infections, were deemed able to cope for the next eight years because the infected people will be diffused in very large populations. But both nations could experience severe problems after that if they fail to curb the epidemic.

These intelligence projections exceed previous estimates by health authorities, making it hard to judge their reliability. But the general thrust of the new report is surely right — that AIDS is gaining momentum in countries whose governments have not given it the high priority needed to stem the epidemic. Officials there need to understand that they are not only facing the prospect of millions of sufferers but of the very fabric of their societies coming unraveled.