“Time will tell whether investors are getting ahead of themselves but a couple of days without a negative Omicron headline has the dip buyers flooding back in,” Craig Erlam, analyst at online trading platform OANDA, said.
The Nasdaq Composite index that groups Big Tech names such as Facebook, Apple, Amazon, Netflix and Google settled up 462 points, or 3%, at 15,687, for its biggest one-day gain since March. Nasdaq rose almost 1% in the previous session.
The Dow Jones Industrial Average, which contains mostly industrial stocks, finished up 492 points, or 1.4%, at 35,719. The Dow gained 1.9% on Monday.
The S&P 500, an index of the top 500 stocks, settled up 95 points, or 2.1%, at 4,687. The index climbed 2.1% in the previous session.
Prior to Monday, US stocks had been battered for weeks, after the discovery of the Omicron variant in South Africa on November 24 and the reporting of the first US case from that on December 1.
Sentiment on Wall Street turned after global medical experts, including top US virologist Anthony Fauci, said at the weekend that early studies on the variant showed its effects might not be as severe as initially feared.