Dec 29 (Reuters) - Canada"s main stock index hit more than a one-month high in thin trading on Wednesday, helped by energy and financial shares, while easing worries over the impact of the Omicron coronavirus variant also boosted sentiment. At 9:39 a.m. ET (14:39 GMT), the Toronto Stock Exchange"s S&P/TSX composite index (.GSPTSE) was up 88.87 points, or 0.42%, at 21,318.55, its highest since Nov. 26. The index rose for a fifth straight session. "Canada"s been closed for two days and the U.S. has been open, so there is a little bit to catch up here," said Colin Cieszynski, chief market strategist at SIA Wealth Management. "It"s not unusual for this week to be relatively quiet because most people are away on holiday." The energy sector (.SPTTEN) climbed 1.5% as oil prices edged towards $80 per barrel on the back of global supply outages and declining U.S. inventories. Early studies showing the Omicron variant has a lower risk of hospitalization than the Delta have helped traders look past the business disruptions caused by the recent surge in cases. The financials sector (.SPTTFS) gained 1.2%, while the industrials sector (.GSPTTIN) rose 0.6%. The benchmark equity index has gained 22% so far this year on hope of an economic recovery and is on track for its best year since 2009. Limiting further gains were healthcare stocks (.GSPTTHC) that fell 4.4%. Major pot producers Cronos Group (CRON.TO), Tilray (TLRY.TO), Canopy Growth Corp (WEED.TO) were down over 8% each. The materials sector (.GSPTTMT), which includes precious and base metals miners and fertilizer companies, lost 0.1% as gold futures fell 1.0% to $1,792.5 an ounce. HIGHLIGHTS The TSX posted 16 new 52-week highs and two new lows. Across all Canadian issues, there were 122 new 52-week highs and 18 new lows, with a total volume of 43.42 million shares.