51�Թ�

But Mr Ricks seemed in little doubt that tariffs would eventually hit and that would have damaging consequences for investment in new medicines.

“It doesn’t have this very, very damaging effect, which is why we recommend vaccination, because we get all of the immunity with none of the adverse consequences,” Bolotin said.

The decline of April Fool's Day news stories comes against "a backdrop of growing scepticism about news in general," Prof Allan adds, "where playing with journalistic credibility may actually prove damaging".

Erdogan has claimed the protests amount to "street terrorism", accusing demonstrators of attacking the police and damaging public property.

Police said there was a violent struggle after officers challenged a man allegedly damaging cars at about 19:00 GMT on 31 January.