BERLIN (REUTERS) - Germany's expert panel on vaccine use on Thursday (Feb 3) recommended Novavax's protein-based Covid-19 vaccine for basic immunisation for people over 18, in a push to win over the more than 15 per cent of German adults still not fully vaccinated.

The high-profile advisory group known as STIKO said a booster shot should still be given with an mRNA vaccine, and particularly vulnerable people should also receive a second booster with an mRNA vaccine.

Novavax's recombinant protein vaccine uses a more established technology than mRNA, the novel method behind the two most commonly used Covid-19 vaccines in Germany, which are from Pfizer/BioNTech and Moderna.

Recombinant protein vaccines have been in use since the mid-1980s and are now a standard tool to fight hepatitis B, the human papillomavirus behind cervical cancer and meningitis-causing bacteria.

Public health leaders have voiced hopes that Novavax's product could convince as-yet unvaccinated people who are sceptical about the novel mRNA technology to get a shot.

Germany expects to receive 3.8 million doses of Novavax's Nuvaxovid vaccine by March 20 and a total of 34 million doses this year.

STIKO also updated its general recommendation for booster shots and now advises at-risk groups including those aged 70 and over, as well as health workers, to get a second booster, or a fourth shot overall, with an mRNA vaccine.

The recommendation comes amid surging coronavirus infections in the country of 83 million. Its vaccination rate lags most western European countries.

The Robert-Koch-Institute for infectious diseases reported a record 236,120 new cases on Thursday.

Health Minister Karl Lauterbach has warned that the numbers could exceed 400,000 by mid-February.

"We have data from Israel that shows a fourth dose significantly improves protection from a severe case of illness," STIKO chief Thomas Mertens told media group Funke in an interview published on Thursday.

Some countries have already started offering additional booster doses, but a recent study from Israel showed that while a fourth dose of an mRNA vaccine boosted antibodies, the level was not high enough to prevent infection with the Omicron coronavirus variant.

In November, STIKO recommended a third shot for all adults and last month updated its advice to include everyone older than 12.

For those aged five to 12, the panel still recommends Covid-19 vaccination only for children with pre-existing conditions.