The global battle against AIDS is yet another victim in the suspected downing of Malaysia Airlines Flight MH17 as six top experts in the research field are believed to have been passengers on the flight.
Joep Lange, former president of the International Aids Society, and five others traveling to an international AIDS conference being held in Melbourne, Australia, were reportedly among those who died in the attack on the airline's Boeing 777 being blamed on Russian-backed Ukrainian separatists.
The aircraft, with 298 people aboard, came down Thursday in eastern Ukraine territory controlled by the separatists.
Early reports had said perhaps as many as 100 AIDS activists and experts may have been on the flight, but that was dismissed by Francoise Barr-Sinoussi, current IAS president.
"It might be a little higher [than six] but not the numbers" some reports presented, she said.
Still, she added, "The extent of our loss is hard to comprehend or express."
Some 14,000 research scientists, politicians and campaigners are attending the AIDS 2014 conference in Melbourne set to begin Sunday.
Although there were initial considerations of cancelling the 5-day event, on the event website organizers announced the gathering would proceed as planned "in recognition of our colleagues' dedication to the fight against HIV/AIDS" and that this year's AIDS Walk would be dedicated to the researchers killed on MH17.
Lange, a professor of Medicine with the University of Amsterdam, was among the pioneers in the effort to understand and treat the disease following the discovery of the HIV retrovirus in 1983.
He was at the forefront of trials of antiretroviral drug therapies, which were successful in turning HIV into manageable disease.
Lang founded the PharmAcces Foundation in 2001, dedicated to getting newly discovered anti-viral drugs to poor people around the globe.
Others on the downed Malaysian Airlines flight who were headed for the conference were Lange's partner Jacqueline van Tongeren, Glenn Thomas, Pim de Kuijer, Maria Adriana de Schutter and Lucie van Mens, the IAS announced.
"This is a profound collective loss to science, to research, to medicine and to public health," said Shaun Mellors, associate director for Africa at the International HIV/AIDS Alliance. "They spent their lives fighting for the lives of others and we pledge to continue their important work."
Among those expected to address the Melbourne conference are former U.S. President Bill Clinton and music star and long-time campaigner Bob Geldorf.