More than 18,000 global leaders, scientists, advocates, and frontline health workers have gathered in Durban for the 21st International AIDS Conference (AIDS 2016), the world's largest forum devoted to any single health or development issue. The conference returns to Durban after 16 years and will feature 2,500 scientific abstracts and hundreds of events.

AIDS 2000 in Durban was a defining moment in the history of HIV/AIDS. It is widely credited with ushering in a global movement to bring life-saving HIV treatment to developing countries, and paving the way for passage of the first United Nations Declaration on HIV/AIDS and the creation of The Global Fund and PEPFAR. Today, more than 17 million people living with HIV are on treatment, and both new HIV infections and AIDS-related deaths are falling.

AIDS 2016 will focus on the work that remains to be done if the world is to achieve the global goal of ending AIDS by 2030. Despite significant progress, more than half of those living with HIV still do not have access to treatment, new prevention tools such as PrEP remain out of reach for most people in need, and the human rights of vulnerable groups are violated in many parts of the world.

Related: The Science Behind a Cure for HIV

At today's official opening press conference, UN Secretary-General Ban Ki-moon warned of an immediate need for more action to avoid backsliding on progress made to date: "As a global community, we must move quickly and decisively towards achieving the targets that will help us finally bring this epidemic to an end."

"This conference comes at another crucial time in the HIV epidemic," said Chris Beyrer, AIDS 2016 International Chair and President of the International AIDS Society. "To truly succeed in all places and for all people, we must ensure that every action we take is grounded in science, respects human rights, and is fully funded for success. If we don't make the right strategic choices, we risk reversing hard-won gains. Delay is tantamount to defeat."

"We have made great strides in South Africa and globally in the fight against HIV, but it is still far too soon to declare victory," said Olive Shisana, AIDS 2016 Local Chair and President and CEO of Evidence Based Solutions. "AIDS 2016 will keep attention focused on the actions needed to write the last chapter in the long struggle against AIDS."

The conference theme, Access Equity Rights Now, expresses the need to overcome ongoing barriers impeding real-world progress, including a lack of funding for HIV prevention, treatment, and research, and the existence of discriminatory laws and policies that affect many of those at greatest risk for HIV, such as men who have sex with men, transgender people, people who inject drugs, and sex workers.

Central to continued success is the leadership of government officials, people living with HIV, civil society partners, and advocates. Others speaking at the opening press conference included Cyril Ramaphosa, Deputy President of South Africa, Michel Sidibé, Executive Director of UNAIDS, Nkhensani Mavasa, Chairperson of South Africa's Treatment Action Campaign, and Charlize Theron, Founder of the Charlize Theron Africa Outreach Project and United Nations Messenger of Peace.

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