Melbourne painted the town red yesterday but it was a time of solemn remembrance rather than celebration.
Handwritten notes, flowers and red ribbons reflected the competing themes of grief and optimism in the overcast city.
"RIP in memory of the many lives sadly lost on the way to beautiful Melbourne," read a note posted on the huge AIDS 2014 sign overlooking the Yarra River.
Another, written by an eight-year-old, thanked those who dedicated their lives to helping others.
Echoing the sentiments of many, it said simply: "We hope you find a cure soon."
As thousands of international delegates arrived for the start of the 2014 global AIDS summit, many were still mourning the loss of some of the leading lights in their field on MH17.
For many, they were not just colleagues, but friends, even family.
Although far fewer delegates perished than first feared, it could not take away from the huge loss of six of their best.
Joep Lange, a prominent HIV researcher and former president of the International AIDS Society, was one of the confirmed victims, as were five other researchers and activists.
The conference's opening ceremony paid tribute to the six, including a minute's silence.
A tearful IAS president Francoise Barre-Sinoussi said she wished they were happier times.
"We dedicate AIDS 2014 to them and for ever keep them in our hearts," she said.
Hundreds of delegates signed condolence books, while others pinned red ribbons on wire tribute boards.
"We used to go to AIDS conferences and grieve for those who died of HIV since the last meeting but today we mourn those who died on MH17," one delegate posted on social media.
They were not alone in their mourning.
Over the weekend, Melbourne's Ukrainian community held a candlelit vigil and Catholic AIDS experts held a special Mass for those lost on the flight. Yet despite flags at half-mast around the city, there was still a sense of purpose, and even optimism.
It was buoyed when Australian health ministers announced an agreement to work towards eliminating any new spread of HIV by 2020, through improved prevention, rapid testing and treatment.
Robert Mitchell, president of the National Association of People with HIV Australia, said no one would ever know what knowledge and future discoveries were lost with the delegates killed.
But he said the HIV community would bounce back because it was used to being resilient in the face of death, and the tragedy would strengthen resolve to address issues such as stigma and discrimination.
Former High Court judge and AIDS activist Michael Kirby said terrible suffering had been inflicted on the families and countries of those who died en route to the summit. "Thinking of their families is a very painful moment, and there's no point denying the pain," he said.
"But we should turn this great misfortune into a resolution to put an end to AIDS, and in a way this terrible event has strengthened the resolve to bring an end to this epidemic."