The world economic outlook has dimmed again, with still-rising coronavirus infections and the risk of renewed lockdowns increasing the chances that any rebound will reverse course, according to Reuters polls of over 500 economists globally.

More than 17 million people have been infected worldwide by the coronavirus and more than 670,000 people have died. That has forced governments to impose strict lockdown measures to curb the spread of the virus, keeping citizens at home and businesses closed and spurring recessions that aren't over yet.

Surging cases in the United States, where related deaths have surpassed 150,000, have led several states to reimpose restrictions. Most economists, long-term investors and even Fed Chair Jerome Powell have clearly said the economic outlook depends significantly on the course of the virus.