The World Bank has called on African governments and international donors to increase efforts to prevent new HIV infections in order to control treatment costs.

In a new report highlighting countries in sub-Saharan Africa, the bank says existing treatment programs could become unsustainable without a “dramatic” drop in new infections.

It says the costs associated with treating HIV and AIDS are like payments made for pension programs – areas governments are committed to funding even as sources of revenue fall.

One of the report's co-authors, Markus Haacker, said countries facing the highest burden are often not those with the highest infection rate, but rather low-income countries that lack the resources to keep pace with each new infection.

The World Bank says the report should encourage the search for long-term funding solutions, while also getting more out of current programs. It recommends intensifying prevention efforts, using regional solutions to bring down costs, strengthening public-private partnerships and improving the use of data on which methods are most effective.

The report says that in Botswana, falling mining revenues threaten to pressure government finances in a country where a quarter of the population between the ages of 15 and 49 is living with HIV.

In Swaziland, the World Bank projects HIV/AIDS costs to be equal to 7 percent of the nation's economy by 2020, and that it will need “substantially” higher outside funding to meet demand.

Global funding for HIV/AIDS rose dramatically from $260 million in 1996 to $15 billion in 2010. But U.N. Secretary-General Ban Ki-moon issued an appeal in December for donors to meet an estimated $24 billion annual need to fully fund global AIDS initiatives.

Sub-Saharan Africa is home to two-thirds of the world's HIV-infected population, despite having only 12 percent of the overall population.