In early trading, the Dow Jones gained 0.73%, the Nasdaq index 1.19% and the broader S&P 500 index 1.07%.

"If you like volatility, then you've probably loved the market these days," Briefing.com analyst Patrick O'Hare summed up in a note.

In fact, although slightly down on Tuesday, the VIX index of the Cboe Derivatives Exchange, which measures market volatility, remained close to its highest level in ten months, reached on Friday.

Another sign of nervousness, bonds remained in high demand, and the average rate of US 10-year government bonds rose only slightly, to 1.47%, against 1.43% the day before.

In great difficulty Friday after the announcement of the discovery of the Omicron variant of the coronavirus, Wall Street tried to recover on Monday before relapsing on Tuesday.

"We are in the middle of a fight between investors oriented to the increase (" bulls ") and those who play the decline (" bears ")," said Adam Sarhan, founder and CEO of management company 50 Park Investments.

"There is this concern related to the spread of the Omicron variant and its consequences on the economy, which explains the market reaction" since Friday, continued the manager.

"But if this variant doesn't cause another wave of massive containment, if it's pretty much contained, then those on the rise will win and the market will pick up momentum."

After being taken aback by the statements of the president of the American Central Bank (Fed) Jerome Powell, ready for an accelerated normalization of the monetary policy of the United States, the operators had digested Wednesday this inflection which they waited for a long time.

"These comments are perfectly in line with the mandate" of the Fed, which is to promote full employment and control inflation, said Adam Sarhan, for whom the market is generally satisfied with this strengthening of the Fed, he who was worried to see prices soar in the long term.

The market reacted little to the report by ADP, which reported 534,000 job creations in the private sector in November, slightly better than expected but lower than the 570,000 creations in October.

At the odds, it's high time for the dematerialized customer relations platform Salesforce (-6.95% to 265.14 dollars), punished for having published forecasts below expectations for its fourth quarter (from November to January) as well than fiscal 2022. Its revenue and profit for the third quarter were, however, above analysts' expectations.

The pharmaceutical group Merck advanced (+ 1.58% to 76.10 dollars) after the publication of a favorable opinion of a committee of independent American scientists to the marketing of its anti-Covid pill, already authorized in the Kingdom -United.

In the same sector, after gaining almost 40% between Thursday and Monday thanks to the Omicron effect, Moderna gradually landed and lost 6.18% to 330.18 dollars.

Same cold snap, in lesser proportions, however, for its competitors Pfizer (-1.43%) and Novavax (-3.66%), which also manufacture vaccines against Covid-19.

Conversely, most of the stocks attacked since Friday were entitled to a breath of fresh air.

Airlines American Airlines (+ 0.97%), United Airlines (+ 1.19%) and Delta Air Lines (+ 1.19%) rebounded, as did cruise lines, including Norwegian Cruise Line (+ 2.56%) ) or oil companies, such as Exxon Mobil (+ 2.18%).

© 2021 AFP