As many as one-third of the passengers on the Malaysian Airlines flight MH17 that crashed in Ukraine were headed to Melbourne, Australia to attend the 20th annual International AIDS Conference (AIDS 2014), which gets underway Sunday.

According to various news sources, as many as 108 of the flight's 298 passengers were bound for the conference, including Joep Lange, a top researcher.

“In recognition of our colleagues' dedication to the fight against HIV/AIDS, the conference will go ahead as planned and will include opportunities to reflect and remember those we have lost,” the International AIDS Society, the conference's organizer, said in a statement.

The Kirby Institute, an Australian-based medical research organization, confirmed in a statement that Lange, who heads the Department of Global Health at the University of Amsterdam, was among the flight's passengers. Also on the plane was Lange's research assistant, Jacqueline van Tongeren.

“Joep was a great source of inspiration for everyone who aimed to contribute to solving the AIDS tragedy in Africa and Asia,” the University of Amsterdam said in a statement. “He was shocked to see how, from 1996 onwards, expensive HIV therapies became available to patients in rich countries, but not in Africa, and he made it his mission to change this and to put an end to the gross inequality in access to life-saving medication.”

“The cure for AIDS may have been on that plane, we just don't know,” Trevor Stratton, an HIV/AIDS consultant, told the Australian Broadcasting Corporation (ABC). “You can't just help but wonder about the kind of expertise on that plane.”

The Human Rights Campaign (HRC), the nation's largest LGBT rights advocate, said in a statement that it was “deeply saddened to learn about the deaths of the many HIV/AIDS advocates believed to be on the plane.”

A vigil was held on Victoria Bridge to honor lost colleagues.