Asian markets struggled Thursday as a week-long rally sputters, with sentiment split between vaccine hopes and Joe Biden's election win on one side and fears over a surge in virus cases that threatens any economic recovery.

The mood across trading floors has been joyous for much of the week after the former vice president toppled Donald Trump and US pharma giant Pfizer said its vaccine candidate had proved to be 90 percent effective.

Hopes that a treatment for the killer disease will be rolled out as soon as this year put a rocket under stocks such as airlines that have been battered for most of the year.

And the news continues to improve on the vaccine front as Moderna said it could now start analysis of its own phase three trials, which US expert Anthony Fauci had earlier said he was optimistic would be as successful as Pfizer's.

Meanwhile, a Russian candidate was said to be 93 percent effective and Shanghai Fosun Pharmaceutical said it had received Chinese approval for a trial.

Observers said the more options that were available would make distribution of any vaccine a lot easier, meaning normal life could return quicker.

"Once we have made it through what is still bound to be a winter of despair for health care concerns, it could trigger the mother of all economic rebounds boosted by unprecedented policy support," said Axi strategist Stephen Innes, pointing to massive central bank and government stimulus efforts.

But while the upbeat outlook largely remains in place, a worrying spike in new infections in the US and Europe has fanned concerns about a deadly winter in the northern hemisphere with several countries already in lockdown.

Several major economies in Europe have shut down or have imposed strict containment measures, while a number of US cities including New York have been forced to act.

And with infection and death rates continuing to spike there are concerns the crisis will extend into the new year.

"In the near term, the resurgence of the virus is beginning to make new worries," Torsten Slok, at Apollo Global Management, told Bloomberg TV. "It looks like this will end up being a W-shaped recovery."

In early trade, most markets were lower with traders taking the opportunity to cash in profits.

Hong Kong, Shanghai, Sydney, Singapore, Seoul, Taipei and Jakarta were all in the red, though Tokyo ended the morning slightly higher and Wellington edged up.

National Australia Bank's Ray Attrill said: "The near-certainty of a horrible few months ahead for the United States (and Europe) given current infection, hospitalisation and death rates, is dominating sentiment just at the moment."

Investors are keeping tabs on developments in Washington as Trump refuses to concede last week's election and has launched legal challenges, claiming without evidence that there was massive electoral fraud.

Vaccine hope offset by virus surge
While hopes are rising for a host of vaccines that could be rolled out soon, the surge in coronavirus cases and deaths across the world is fuelling concerns about the recovery. Photo: AFP / STR

His stubbornness has fuelled concerns about the transition to Biden and also led to questions about whether US lawmakers will be able to push through a much-needed stimulus package for the troubled economy.

Oil prices edged up on reports OPEC and other major producers led by Russia are considering a delay to a planned increase in output following months of cuts that were put in place to prevent a market collapse.

The so-called OPEC+ is considering looking at extending the reduction agreement in place for up to another six months when they meet later this month.

Tokyo - Nikkei 225: UP 0.4 percent at 25,459.13 (close)

Hong Kong - Hang Seng: DOWN 0.1 percent at 26,211.37

Shanghai - Composite: DOWN 0.2 percent at 3,334.51

Euro/dollar: DOWN at $1.1780 from $1.1781 at 2115 GMT

Pound/dollar: DOWN at $1.3216 from $1.3218

Dollar/yen: DOWN at 105.31 yen from 105.42 yen

Euro/pound: UP at 89.14 pence from 89.11 pence

West Texas Intermediate: UP 0.5 percent at $41.67 per barrel

Brent North Sea crude: UP 0.5 percent at $44.02 per barrel

London - FTSE 100: UP 1.4 percent at 6,382.10 (close)

New York - Dow: DOWN 0.1 percent at 29,397.63 (close)

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