COPENHAGEN: Europe and pharma groups must work together to speed up Covid-19 vaccinations, the head of the European branch of the World Health Organization said Friday, expressing concern about the effectiveness of vaccines on virus variants.

"We need to join up to speed up vaccinations," WHO Europe director Hans Kluge told AFP in an interview, as Europe bids to overcome a slow start to its vaccination campaign amid tensions between Brussels and vaccine manufacturers.

"Otherwise competing pharmaceutical companies (must) join efforts to drastically increase production capacity ... that's what we need," Kluge said.

In the European Union, just 2.5 percent of the population has received a first vaccine dose, though announcements by several laboratories of increased vaccine deliveries have raised hopes of an acceleration.

Asked whether the vaccines available since December would be effective against new virus variants, Kluge replied: "That's the big question. I'm concerned."

"We have to be prepared" for new problematic mutations of the virus, he warned, calling on countries to expand their genomic sequencing capacity.

"It's a cruel reminder that the virus still has the upper hand on the human being."

'Tunnel a little bit longer'

Of the 53 countries in the WHO's European region -- which includes several countries in central Asia -- 37 have reported cases of the British variant and 17 have registered cases of the South African variant.

While the fight against the pandemic now appears more challenging than in December when the first vaccines became available, Kluge remained optimistic.

"I'll be honest, I think that the tunnel is a little bit longer than what I thought at the end of December, but it's going to be manageable, more preventable this year."

"'The' solution or 'the' strategy doesn't exist. We have to get better at what we do and we are getting better," he said.

He reiterated the WHO's call for rich countries to show solidarity toward poor nations unable to buy vaccines, urging wealthy ones to share their doses after having inoculated a portion of their own population.

"Maybe if EU countries vaccinate 20 percent of their population -- -- and you need 70 percent for herd immunity -- but we could say for example that if they hit 20 percent would mean elderly people, health care workers, people with comorbidity -- if they hit 20 percent maybe that's the moment that they can already start to share some vaccines," he suggested.

The milestone of 100 million vaccine doses administered was passed on Tuesday, with 65 percent of jabs given in high-income countries, according to World Bank criteria.