Australia should keep a close eye on how Donald Trump battles his COVID-19 infection, according to one of the country's leading scientists.

The treatment being provided to United States President Donald Trump could pave the way to fighting COVID-19, says one of Australia's top scientists.

Professor Peter Doherty, who shared the Nobel Prize for Medicine in 1996 for his work on how the immune system recognises virus-infected cells, says a vaccine might not be the only answer.

"Vaccines will help a lot - they'll shift the bar, but I don't think they're going to end the problem," he told the Melbourne Press Club on Monday.

President Trump is being treated with Remdesivir, an antiviral drug, as well as an eight-gram infusion of monoclonal antibodies.

Prof Doherty said monoclonal antibodies could be made in large quantities, were "highly specific" and "really powerful".

And in good news for Australians, the country has the ability to manufacture them through Melbourne-based biotechnology company CSL.

"We're hoping these are going to work really well on President Trump ... because that's our best shot out there at the moment for a specific therapy," Prof Doherty said.

"We're lucky that we've retained CSL in Australia and we have the capacity to make large amounts of monoclonal antibodies.

"One of the problems with this, as we develop therapies and vaccines come forward, is actually getting the product ... (so) having CSL here is a big plus."

But in potentially bad news for President Trump, Prof Doherty said the lack of information regarding the long-term effects of coronavirus was "very concerning".

"Even people who don't get hospitalised - there are cardiac problems, myocardial damage, kidney damage," he said.

"The reason diabetics are so susceptible is probably because they have already got kidney damage.

"There's a whole yet we don't understand about (the long-term damage) and better understanding would feed into better therapy."

Meanwhile, Prof Doherty said while a COVID-19 vaccine candidate could be rolled out in the United States early next year, the potential effectiveness remains unknown.

He noted first results from the likes of America's Operation Warp Speed, a public-private partnership which has five vaccines undergoing trials, could be revealed later this month.

"Will they be like the influenza vaccine, where they're 40 to 60 per cent effective? Or will they be like measles vaccine, which is over 90 per cent effective - we don't know," said Prof Doherty, who's also the patron of Melbourne's Peter Doherty Institute for Infection and Immunity.

"The way out of this is going to be interesting and politically challenging."

On Sunday, President Trump's doctors said his health was improving and that he could be discharged as early as Monday after he was admitted to hospital last week.

His medical team also reported his blood oxygen level dropped suddenly twice in recent days and that they gave him a steroid typically only recommended for the very sick.

But they sidestepped questions about whether lung scans showed any damage.