The Ross River virus risks becoming a global epidemic on the same scale as the Zika virus, Australian researchers say.

An Australian National University and University of Adelaide study has found that Ross River transmitted by mosquitoes could be carried by placental mammals and not just marsupials as previously thought.

"The traditionally accepted thinking and all evidence points to the fact that the virus needs a marsupials reservoir – so when kangaroos and wallabies are around - and it then gets picked up by a mosquito which then transmits it to humans," University of Adelaide professor Philip Weinstein told AAP.

"What the new research shows is that it can do this without the marsupials ... you could have dogs, cats and rats playing the role that we thought only marsupials could do."