NEW YORK: Wall Street stocks mostly gained early Monday, launching the so-called Santa Claus rally amid hopes the impact of the latest Covid-19 strain will be limited, while travel-related stocks took a hit.

Infections from the Omicron variant have soared in recent days, but health experts are hopeful the newest Covid-19 outbreak will not be as deadly as earlier versions, nor require severe lockdowns.

The market's view is that "Omicron is going to be a nuisance but not a dire strait for the global economy -- at least not for long," said Briefing.com analyst Patrick O'Hare.

The session opened a seven-day stretch starting just after Christmas known as a historically strong season for stocks, a period marked by low trading volumes.

About 15 minutes into trading, the Dow Jones Industrial Average was up 0.3 percent at 36,052.67.

The broad-based S&P 500 gained 0.5 percent to 4,749.44, while the tech-rich Nasdaq Composite Index jumped 0.6 percent to 15,743.79.

Most sectors advanced early Monday, but leading airlines like United and Delta dropped more than two percent, amid mass flight cancelations caused by infections or quarantines among airline and airport staff.

Cruise companies Carnival and Norwegian also fell into the red, as did Expedia and Hilton Worldwide.