“We are seeing increased rates of transmission across all age groups,” Maria van Kerkhove told a WHO briefing on Monday, adding that 5.2 million cases were reported last week, the highest weekly increase since the start of the pandemic.

“We are seeing a slight age shift in some countries, driven by social mixing,” she added.

WHO chief Tedros Adhanom Ghebreyesus said the global figure was the eighth consecutive weekly increase.

The number of coronavirus-linked deaths reported has also risen steadily for five consecutive weeks, he said.

“It took nine months to reach 1 million deaths, four months to reach 2 million and three months to reach 3 million.”

Of particular concern is the rise in cases and hospitalisations among people between ages 25 and 59, he said.

The increase may be due to the more contagious variants and the fact that there is more social contact among this age range, Tedros said.

“We have the tools to bring this pandemic under control in a matter of months, if we apply them consistently and equitably,” he said.

Those tools include protective measures such as hand washing, maintaining physical distancing and wearing masks, alongside vaccinations.

Mike Shields and Stephanie Nebahey in Geneva