"In addition to the fast-rising human toll of the virus, we are entering a period of unprecedented rates of decline in economic activity and financial-asset prices, and equally fast and unprecedented policy responses to both combat and offset these declines," said Paul Gruenwald, global chief economist at S&P Global Ratings, in the report.
The U.S. is now expected to contract by 1.3% in 2020, down from -0.5% to zero in the previous update. Growth in 2021 is expected to be 3.2%.
A 2% contraction is expected for the eurozone, compared with -1% to -0.5% in the March 17 update. For 2021, growth is expected to reach 3%.
China's growth forecast was revised upward to 2.9%, from 2.7% in the previous update. For 2021, growth is expected to reach 8.4%.
Global industrial production is expected to decline by 2% in 2020, with different sectors hit to varying degrees over the coming quarters, said a separate report by global advisory firm Oxford Economics.
Under a worst-case scenario, production could fall 3% this year, according to the Oxford Economics report, also published Tuesday.
Manufacturing output, excluding the extractive and utilities sectors, is forecast to shrink by 2.8% this year, with a 5.5% first-half drop in the three months ended Tuesday.
U.S. manufacturing output is forecast to be down 0.7% in the first quarter, followed by a 5.2% contraction in the second quarter. For the eurozone, manufacturing is set to shrink by 1% in the three months ended Tuesday and a further 4.6% fall in the second quarter.
By sector, the automotive, textiles and furniture manufacturing industries are the most vulnerable to a pause in consumer spending. The automotive sector is forecast to see a 10.2% contraction for 2020, the Oxford Economics report added.
However, a strong recovery is expected toward the end of this year and into 2021.