The latest estimates from UNAIDS show 34 million people were living with HIV in 2010, and nearly 30 million have died from AIDS-related causes over the past 30 years. 1.4 million people had started life-saving treatment last year - more than any previous year. And at least 420-thousand children were receiving anti-retro-viral therapy, a 50 per cent increase since 2008.

Patients and curers at the Hillcrest HIV Trust in Durban held a memorial service for friends and patients who have died of AIDS-related illnesses at the hospice.

South Africa, a nation of about 50 million, has an estimated 5.7 million people infected with HIV, the highest in the world. Expanding treatment is a financial and social challenge.

Mary-Anne Carpenter, head nurse of Hillcrest Aids Trust said: "I think we are making progress, slowly, in our country, but it's thanks to a civil society. We fight hard for what we've got around HIV/AIDS and ARVs (Anti Retro-Virals - HIV drugs)."

The country has released a film, "Inside Story", aimed at those who do not fully understand the science of AIDS.

It follows the life of an infected Kenyan footballer in South Africa, with a Nigerian girlfriend, to send the message that the virus is a pan-African problem.

In Israel, a group of illustrators exhibited cartoons in Tel Aviv to inject some humor into the campaign.

And a large tree made of 733 red ribbons, and a wall of condoms was placed at a plaza in Seoul, South Korea, to mark the day.

Officials from South Korean health ministry, Korea Centres for Disease Control and Prevention, Korea Federation for HIV/AIDS Prevention and the public gathered to send messages of support to AIDS patients.

Kim Min-ki, chairman of Korea Federation for HIV/AIDS Prevention said: "Now AlDS is a controllable disease. It is treatable, not an untreatable one. It can also be fully prevented if people have the correct perception of AIDS."

And in Hong Kong the city's landmark Clock Tower was lit red to raise public awareness.

In Washington US President Barack Obama has vowed to renew US commitment to tackle HIV and AIDS, setting goals for increasing access to life-saving AIDS drugs and boosting spending on treatment in the US by 50 million dollars.

Senior officials say the goal is to give anti-retro-viral drugs to two million more people around the world by the end of 2013.

The US will also aim to give drugs to 1.5 million HIV-positive pregnant women, to prevent the virus passing to the next generation.