BRUSSELS — The massive spike in COVID-19 cases in recent weeks is threatening the European Union’s recovery from the deep economic slump caused by last year’s onset of the pandemic, the bloc’s economy chief said Wednesday.

And medical experts warned that the public health situation could get much worse.

Only two weeks ago the EU executive forecast 5% growth in the 19-nation eurozone for an economy bouncing back from the worst of the pandemic. But EU Economy Commissioner Paolo Gentiloni said Wednesday that the upbeat picture was now in doubt again amid rising infections and with restrictions being reintroduced in a growing number of member states.