The UN on Tuesday urged countries to "break the AIDS epidemic" by doubling the number of people receiving HIV treatment within the next five years.
In a new report, UNAIDS hailed "extraordinary" progress in the fight against HIV and AIDS over the past 15 years, insisting the world had a chance of meeting the UN goal of eliminating AIDS as a global health threat by 2030.
"We have moved from despair to hope," UNAIDS chief Michel Sidibe told reporters in Geneva at the launch of the report.
But to keep up the momentum and ensure the virus does not spiral out of control again, far more people need to access treatment, he warned.
"Every five years, we have more than doubled the number of people on treatment, which is just amazing," Sidibe said, pointing out that virtually no one was receiving treatment 20 years ago.
Avoid 22 million deaths
"We need to do it just one more time to break the AIDS epidemic and keep it from rebounding," he said, stressing that by doing so, "we will be able to avoid 28 million new infections, we will be able to avoid almost 22 million (AIDS-related) deaths."
In its latest report, UNAIDS said the number of people accessing antiretroviral therapy had sky-rocketed from just 2.2 million worldwide in 2005 to 7.5 million in 2010 to 15.8 million by June this year.
However the figures still indicate that less than half of the estimated 36.9 million people living with HIV today are receiving the treatment.
"Once diagnosed, people need immediate access to antiviral therapy," UNAIDS said.
Overall, UNAIDS hailed extraordinary advances in the fight against HIV and AIDS, with annual new infections down by more than a third globally between 2000 and 2014 to around two million.
The number of AIDS-related deaths meanwhile fell 42 percent from its peak of two million in 2004 to 1.2 million last year.
"Progress has been achieved in each region of the world. But the pace is too slow," Sidibe said.
Tuesday's report listed 35 countries that account for 90 percent of all new HIV infections and which it said needed particular attention.
Countries in sub-Saharan Africa remain the hardest-hit, accounting for 66 percent of all new infections last year, and counting 790,000 AIDS-related deaths.
But the region has been making great strides to rein in the epidemic, with new cases there down 41 percent between 2000 and 2014 and AIDS-related deaths down 48 percent since 2004.
Some 10.7 million of the 25.8 million people living with HIV in the region meanwhile are now receiving treatment, compared to fewer than 100,000 in 2002, the report said.
Punitive laws boost epidemic
Other regions are not doing as well.
In Eastern Europe and Central Asia, new HIV infections rose by 30 percent between 2000 and 2014, while new cases swelled 26 percent during the same period in the Middle East and North Africa.
Sidibe warned that the epidemic tends to "grow very, very quickly" among populations at risk in countries where they cannot access preventive services, due for instance to "homophobic laws" or lack of recognition of sex workers.
"Punitive laws are the key real barrier in many cases," he said.
He hailed countries that are striving to make new treatments available, like France, which on Monday announced it aims to provide the new preventive treatment Truvada free of charge to high-risk populations.
"Our prevention arsenal is expanding," he said, stressing that the pre-exposure prophylaxis should be used in combination with other preventive measures, including condom use.
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