SHANGHAI—AIDS has killed 25 million people worldwide but new infections are slowing sharply, the UN said in an annual report on the crisis Tuesday that mixed hope with a warning against complacency.

Almost 60 million people have been infected by the HIV virus since it was first recorded but prevention programs are having a significant impact, the United Nations Joint Program on HIV/AIDS (UNAIDS) said in its latest report, released here in Shanghai.

Around two million people died of the disease in 2008, bringing the overall toll to around 25 million since the virus was first detected three decades ago.

Some 2.7 million were newly infected in 2008, it added, bringing the world total to 33.4 million.

Michel Sidibe, UNAIDS executive director, told a Shanghai press conference on the report's launch that the number of new human immunodeficiency (HIV) virus infections has been reduced by 17 percent over the past eight years.

"The good news is that we have evidence that the declines we are seeing are due, at least in part, to HIV prevention," Sidibe said.

Some of the most notable progress has been reported in Africa, the report said.

HIV incidence has fallen by 25 percent since 2001 in East Africa while the figure for sub-Saharan Africa as a whole was around 15 percent—equating to around 400,000 fewer infections in 2008.

In South and South East Asia, HIV incidence has declined by 10 percent in the same time period, the report said.

Sidibe said treatment products had increased ten-fold in the past five years, leading to an 18 percent decline in mortality since 2001.

But he added better prevention strategies were needed to stop new infections, which stood at 7,400 a day.

"Any time we are putting two people on treatment, five people are being infected," he said.

"The findings (of the report) show that prevention programming is often off the mark and that if we do a better job of getting resources and programmes to where they will make most impact, quicker progress can be made and more lives saved," the official added.

The new report showed that more people than ever were now living with the virus as people live longer due to the beneficial effects of antiretroviral therapy.

The number of deaths linked to AIDS has declined by over 10 percent over the past five years as more people gained access to life saving treatment, said the report.

It estimated that around 2.9 million lives have been saved since 1996 when more effective treatment became available.

"International and national investment in HIV treatment scale-up has yielded concrete and measurable results. We cannot let this momentum wane," said Margaret Chan, head of the UN's World Health Organization (WHO).

"Now is the time to redouble our efforts, and save many more lives," the official said.

Sibide said that AIDS, which was first declared as having reached epidemic proportions in 1981, was evolving and that research in some of Africa's worst affected countries had shown it having an increasingly significant impact on maternal mortality.

"Half of all maternal deaths in Botswana and South Africa are due to HIV," he said.

"This tells us that we must work for a unified health approach bringing maternal and child health and HIV programmes as well as tuberculosis programmes together to work to achieve their common goal."