The AIDS community is familiar with the loss of life, but not like this.

Six, and possibly more, prominent figures in the fight against the disease were onboard Malaysia Airways flight MH17 enroute to an international conference in Melbourne.

News of the plane’s mid-air destruction over Ukraine, apparently at the hands of Russian-backed separatists, has cast a sombre mood over the event focused on one of the world’s major diseases.

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“This is a community that was built on loss, and knows so much about loss, but then this feels like such a different kind,” AIDS 2014 attendee Mathew Rodriguez, from New York City, told AAP on Saturday.

“Not that there is any sense in HIV, but this feels like such a senseless loss.

“We are a community that knows so much about people dying but to have it in this way is really devastating.”

The International AIDS Society on Saturday released the names of the six leading HIV researchers and advocates, while noting more names could come to light.

These include former IAS president Joep Lange, considered a giant of HIV research, and his partner Jacqueline van Tongeren who is also a prominent public health official.

Parallels have been drawn to the deaths of former WHO official and HIV pioneer Dr Jonathan Mann and his wife, a vaccine scientist, who were killed in a Swissair plane crash in 1988.

“You know it reminds me of Jonathan Mann and his wife when they were killed on the way to an AIDS conference. This is another huge loss, a huge loss,” attendee David Evans, from San Fransisco, said.

“Joep had a huge impact on HIV science internationally and his loss will be deeply, deeply felt – there is no question.”

Mr Evans also said it was a particularly tragic example of geopolitical events impeding efforts to better control the spread of HIV, while noting transmission was surging both in Russia and the Ukraine.

The conference gets underway on Sunday and it would be a “little more quiet … a little more morose” than in the past, another attendee said.

“Thousands of people die every day from HIV,” Myles Helfand, also from New York City, said.

“Anything that makes humanity worse is made worse by the loss of people who could potentially do something about it.”