The Greens are calling on the Federal Government to support personal importation of an HIV 'wonder drug' that has just been denied listing on the Pharmaceutical Benefits Scheme, to protect those who are most at risk.

"We simply cannot leave Australians at unnecessary risk, when this drug gives us the chance to end HIV transmission in Australia," said Greens Leader Dr Richard Di Natale, a former public health specialist who has worked on HIV prevention in India.

The Australian Greens say the MH17 disaster is a horrific tragedy that will reverberate around the world.

"Our hearts go out to the families and friends of all those who have been killed, especially the 27 Australians reported to be on board," said Greens Leader Senator Christine Milne.

"Tragedies like these always touch many more people than we can ever know, but it is shocking news that up to 108 delegates to the 20th Annual AIDS Conference due to be held in Melbourne this weekend were on board the doomed flight.