One in seven cases of Covid-19 reported to the World Health Organisation (WHO) is a health worker and in some countries that figure rises to one in three, the agency said.

“Globally around 14 per cent of Covid cases reported to the WHO are among health workers and in some countries it's as much as 35pc,” WHO Director General Tedros Adhanom Ghebreyesus said, Reuters reported.

He added data was limited and it was hard to know if people were infected at work or in their communities.