"As these budget trade-offs are made, the voices of the AIDS community and the global health community are going to have to be louder than ever," said Gates, whose Bill & Melinda Gates Foundation has pledged more than $1 billion to global AIDS efforts.
Another $7 billion a year is needed to get 15 million people in low- and middle-income countries onto medication by 2015, a United Nations goal. A record 8 million received it last year.
"We have to be innovative," said Sheila Tlou, the former health minister of Botswana, now with UNAIDS. "We have to look at new ways of funding."
Speaking to the conference via video, French President Francois Hollande said his country was doing that by beginning what's called a financial transaction tax next month. The tax idea has received a lukewarm reception in other parts of Europe and the U.S.
And researchers from Zimbabwe described how individuals and companies in that country pay 3 percent of taxable income into a National AIDS Trust Fund that has grown large enough to fund anti-AIDS medicines for a quarter of patients using them.
Associated Press writer Joshua Lederman contributed to this report.
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