US STOCKS-Oil recovery drives gains on Wall Street
* Brent crude up above $40 per barrel
* Valeant surges after Pershing Square gets board seat
* Chipotle down as 4 employees fall ill
* Indexes up: Dow 0.27 pct, S&P 0.31 pct, Nasdaq 0.16 pct (Updates to open)
By Abhiram Nandakumar
March 9 (Reuters) - Wall Street was higher on Wednesday morning, led by energy stocks, as oil prices rose on hopes of major producers agreeing to freeze output.
Brent crude hovered above $40 a barrel on Wednesday. However, industry watchers remain skeptical of a sustained recovery in prices due to the oversupply.
"Obviously, it's about oil prices," said Peter Cardillo, chief market economist at First Standard Financial in New York.
"The market is probably going to have an upward bias for most of the session as investors await the ECB (decision) tomorrow," he said. Continuación...