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* Travel stocks edge higher after vaccine update

* Nasdaq in front; communications services lead sector gains

* Indexes: Dow down 0.1%, S&P 500 up 0.1%, Nasdaq up 0.5%

NEW YORK, Dec 8 (Reuters) - The S&P 500 and Nasdaq crept slightly higher on Wednesday, as investors cheered encouraging news about COVID-19 vaccines from Pfizer and BioNTech.

Pfizer and BioNTech said their three-shot course of the vaccine was able to neutralize the new Omicron variant in a laboratory test and they could deliver an upgraded vaccine in March 2022 if needed.

Travel stocks rebounded, with the S&P 1500 Airlines index up 2.2%.

Still, many investors remained worried the Omicron variant could force new restrictions in countries and hurt the global recovery. In a bid to slow its spread, Britain said it could implement tougher measures, including advice to work from home, as early as Thursday.

Sector gains were led by communication services, which rose 0.6%. The Nasdaq was outperforming.

"Nasdaq's doing well and the Dow isn't doing well. That's a perfect risk-on kind of day." said Paul Nolte, portfolio manager at Kingsview Investment Management in Chicago.

"A lot is revolving around virus news. It's a reopening trade more than anything else."

The Dow Jones Industrial Average fell 19.99 points, or 0.06%, to 35,699.44, the S&P 500 gained 6.36 points, or 0.14%, to 4,693.11 and the Nasdaq Composite added 71.30 points, or 0.45%, to 15,758.22.

WHO director-general Tedros Adhanom Ghebreyesus said governments should urgently reassess their national responses to COVID-19 and accelerate their vaccination programs.

Goodyear Tire & Rubber Co rose 2.9% after Deutsche Bank upgraded the stock to "buy" from "hold".

Stanley Black & Decker added 3.7% after Sweden's Securitas agreed to buy its electronic security solutions business for $3.2 billion.

Advancing issues outnumbered declining ones on the NYSE by a 1.58-to-1 ratio; on Nasdaq, a 1.97-to-1 ratio favored advancers.

The S&P 500 posted 29 new 52-week highs and no new lows; the Nasdaq Composite recorded 30 new highs and 36 new lows. (Additional reporting by Devik Jain and Shreyashi Sanyal in Bengaluru; Editing by Maju Samuel)