The number of people across the world living with HIV is still rising, a UNAids report is set to show.
The UNAids report will detail the incidence of HIV/Aids around the world
But the report is also expected to show that the rate of new HIV infections is decreasing in several countries.
Over 39m people are currently estimated to be living with the virus that can lead to patients developing Aids.
The report is also due to call for prevention programmes to be strengthened and sustained to reduce the spread of HIV/Aids.
The report, due to be released on Monday, will include updated figures on how many people are estimated to have HIV/Aids in regions of the world.
It will also look at how the disease's spread is changing.
Lisa Power, head of policy at the UK's Terrence Higgins Trust, said: "The global epidemic continues to grow.
"We know that HIV prevention campaigns are increasingly important and increasingly urgent.
"Preventing HIV is far more effective than treating its aftermath."
And Deborah Jack, chief executive of the National AIDS Trust, said: "While HIV rates continue to rise throughout the world, a long-term strategy is vital to beat the pandemic.
"A greater range of prevention tools are needed as currently millions of women in developing countries who cannot insist on condom use are defenceless against HIV infection, causing unnecessary illness and death.
"Worldwide commitment to research into microbicides and vaccines is essential if we are to make these a reality in the next decade and bring hope to millions."
Last year's report highlighted increases in HIV cases in East Asia, Eastern Europe and Central Asia, and said rates in women were outstripping those in men in some regions.
As well as being biologically more vulnerable to infection than men, women are forced to have sex through violence or financial reasons, said UNAids.