The enormous number of people infected with HIV in Russia, China, and India is poised to grow even larger, thus altering the economic potential and military power of Eurasia's largest states.

At present, the HIV/AIDS pandemic, though global, is overwhelmingly concentrated in sub-Saharan Africa. Although this situation has exacted a terrible human cost, the rest of the world has been largely unaffected by Africa's tragedy.

Things will be very different, however, in the next major area of HIV infection. Eurasia (which for the purposes of this essay is considered to be the territory encompassing the continent of Asia plus Russia) will likely be home to the largest number of HIV victims in the decades ahead.

Several facts are clear about current HIV infection in Eurasia.

First, regardless of the sources one prefers, enormous numbers of people are already infected with HIV in Russia, India, and China.

If one trusts United Nations' AIDS estimates, the total for the three countries already exceeds 5.5 million; if one prefers the U.S. intelligence community's statistics, the collective figure may be as high as 12 million.

Second, in each of these countries, the continued rapid transmission of HIV is assured and is poised to "break out" into the general population.

Russia and China in particular seem to have special potential "epidemiological pumps'' for exposing broad segments of their populations to HIV risk--in the former, the spread of disease via the national prison system, and in the latter, the prevalence of HIV-tainted blood transfusions combined with the newfound mobility of the rural poor.

Since there is no reliable method for accurately forecasting the long-term trajectory of the HIV/AIDS pandemic, I have used statistical techniques to project from current data three future epidemic scenarios. Under these scenarios, the estimated cumulative death tolls from 2000 to 2025 are:

• Severe: China, 58 million; India, 85 million; Russia, 12 million.
• Intermediate: China, 40 million; India, 56 million; Russia, 9 million.
• Mild: China, 19 million; India, 21 million; Russia, 3 million.

As these figures suggest, HIV/AIDS is poised to exact a staggering human toll over the next quarter-century in Eurasia--and this without even approaching the infection rate of sub-Saharan Africa.

Indeed, China, India, and Russia together could experience more HIV infections and AIDS deaths over the coming quarter-century than the entire planet has thus far.

The economic costs of the disease in these three pivotal countries will be vastly larger than they have been in sub-Saharan Africa. Moreover, given how the disease spreads, some key Eurasian populations will be harder hit than others--and some regional governments will prove less competent than their neighbors (and competitors) in handling the crisis that ensues.

There are still things states can do to at least limit the risk of contagion within their populations.

Governments can competently monitor the spread of the disease and warn their citizens accordingly. They can engage in public education campaigns to apprise their people of the deadly risks they face with HIV, urging them to alter specific behaviors. They can attend to the explosion of curable sexually transmitted infections, since these have proved to be a leading indicator for HIV transmission. And they can intervene with groups at high risk of HIV to encourage lifestyles that will court fewer dangers. But governments in Eurasia are not yet doing enough of these things.

The spread of HIV/AIDS through Eurasia, in short, will assuredly qualify as a humanitarian tragedy--but it will be much more than that.

The pandemic there stands to affect, and alter, the economic potential--and by extension, the military power--of the region's major states. And the disease will do more damage to some big countries than to others.

Over the decades ahead, in other words, HIV/AIDS is set to be a factor in the very balance of power within Eurasia--and thus in the relationship between Eurasian states and the rest of the world.