The Dow Jones Industrials enjoyed strong gains of 91.91 points to 25,475.02.
The S&P 500 added 11.42 points to 3,055.73.
The NASDAQ Composite picked up 62.18 points to 9,552.05.
The S&P 500 closed at its highest level since early March while the NASDAQ ended the session at levels not seen since late February.
Stocks closely linked to the economy reopening led the slight gains. Carnival, Norwegian Cruise Line and Royal Caribbean were all up at least 6.7%. Hilton Worldwide climbed 3.3% and Marriott International advanced 7.4%. American Airlines sprang up 5.8% and Delta advanced 3.8%, while United went airborne 5.1%.
Those gains were slightly offset, however, by a 7.2% drop in Pfizer shares.
Last week’s gains led the major averages to their first back-to-back monthly advances since late 2019. The Dow advanced 4.3%, and S&P 500 gained 4.5%, for May while the NASDAQ amassed 6.8%.
More than six million coronavirus cases have been confirmed globally, including over 1.7 million in the U.S., according to Johns Hopkins University. However, Novavax said last week is started Phase 1 clinical trials for its coronavirus vaccine candidate while Moderna said May 18 its early stage vaccine trial had yielded positive results.
Prices for the 10-Year Treasury slid, raising yields to 0.66% from Friday’s 0.65%. Treasury prices and yields move in opposite directions.
Oil prices eked up four cents to $35.53 U.S. a barrel.
Gold prices dropped 90 cents to $1,750.80 U.S. an ounce.