WASHINGTON—The global economy is expected to expand 4 percent in 2021 after shrinking 4.3 percent in 2020, the World Bank said on Tuesday, although it warned that rising COVID-19 infections and delays in vaccine distribution could limit the recovery to just 1.6 percent this year. The World Bank’s semi-annual forecast showed the collapse in activity due to the coronavirus pandemic was slightly less severe than previously forecast, but the recovery was also more subdued and still subject to considerable downside risk. “The near-term outlook remains highly uncertain,” the bank said in a statement. “A downside scenario in which infections continue to rise and the rollout of a vaccine is delayed could limit the global expansion to 1.6 percent in 2021.” With successful pandemic control and a faster vaccination process, global growth could accelerate to nearly 5 percent, it said in its latest Global Economic Prospects report. The pandemic is expected …