U.S. economic activity increased modestly in recent weeks and a growing number of the Federal Reserve’s districts saw a drop in employment as a surge in coronavirus cases led to more shutdowns of businesses, the U.S. central bank said on Wednesday.  In the Fed’s latest “Beige Book” report, a collection of anecdotes from businesses across the country, Fed officials revealed how the pandemic’s imprint varied by region and industry as rising infections dampened the optimism promised by the arrival of effective coronavirus vaccines. Indeed, the vaccine rollout was a frequently cited source of optimism in many of the Fed’s 12 regional districts, with 10 mentions in the report, twice the number in the previous Beige Book that was released in early December. “Although the prospect of COVID-19 vaccines has bolstered business optimism […]