Washington, Jan 18 (IANS): US drugmaker Moderna is working on a combined Covid-19 and flu booster shot, which could be available in some countries by fall 2023 at the earliest, CEO Stephane Bancel has said.

In his speech at the Davos Agenda, a virtual event being held this week by the World Economic Forum, Bancel said this date was a "best case scenario", but that he believed it was possible for some countries next year, CNN reported.

He explained it was a goal for the company to have a single annual booster shot available to avoid "compliance issues" where people are wary about getting multiple shots every winter.

Meanwhile, Bancel also said that the company will have data available on its Omicron-specific Covid-19 vaccine in March

"It should be in the clinic in the coming weeks. And we're hoping in the March timeframe, we should be able to have data to share with regulators to figure out the next step forward," he was quoted as saying in a panel conversation at Davos.

"That's always been a great partnership between public health experts, the regulators and vaccine makers to figure out what's the best path," he said.

Scientists at Pfizer are also using the mRNA technology that helped Covid-19 vaccines succeed in exploring ways to inoculate the masses from the flu.

According to Pfizer CEO Albert Bourla, its Omicron specific vaccine will be ready by March, while AstraZeneca is also looking at a variant specific jab.