USD strengthened against its major rivals in the European session on Thursday as rising coronavirus cases in the U.S. and other key world economies heightened worries over the potential fallout from COVID-restrictions on the global economy, curbing risk sentiment, which was boosted by upbeat vaccine news.

According to the latest data from Johns Hopkins University, the number of coronavirus- infected people in the U.S. increased to 11,531,451, the most in the world. Meanwhile, the death toll from coronavirus reached 250,548, also the most in the world. Overall, the total number of confirmed global coronavirus cases rose to  56,394,215 and deaths grew to 1,352,188. 

Investors worry that, while the world waits for any COVID-19 vaccine to be approved and distributed, the governments are forced to impose tighter restrictions to slow the spread of the coronavirus, which will lead to further economic damage.

On Wednesday, New York Governor Cuomo announced that New York City public schools will temporarily close due to surging coronavirus cases. 

In addition, a much-needed stimulus bill is unlikely to be immediately approved by the U.S. Senate.