(Adds details CFRA comments, second Norovirus case in Virginia)
LOS ANGELES, July 24 (Reuters) - Shares of Chipotle Mexican Grill Inc lost more ground on Monday, after analysts cut stock price targets and raised doubts about whether the burrito chain can raise menu prices to offset higher costs.
The chain's stock shed nearly 13 percent of its value last week on reports of a Norovirus outbreak at a restaurant in Sterling, Virginia, and mice in a Dallas eatery. The shares slipped another 0.5 percent to $343.52 in afternoon trading on Monday after touching $336.65, their lowest intraday level since April 2013.
The move in the stock reveals the fragility of Chipotle's recovery from a sales-crushing string of food safety outbreaks in late 2015, when public health officials linked E. coli, Salmonella and Norovirus outbreaks to the chain.
Chipotle's stock flirted with $750 prior to the food safety lapses.
CFRA Research analyst Tuna Amobi on Monday chopped his 12-month price target by more than a third, reducing it by $190 to $350 per share, and downgraded Chipotle shares to "hold" from "buy."
Amobi cut 2017 earnings per share estimates by 46 cents to $8 and took his 2018 target down 25 cents to $11.68, citing the latest Norovirus and rodent headlines.
"We infer major setbacks to (Chipotle's) ongoing recovery efforts after (2015) health-related concerns on virus outbreaks at several locations that precipitated a steep and protracted downturn in customer traffic," Amobi wrote.
Credit Suisse analyst Jason West also cut Chipotle's price target to $325 from $425.
"We believe the recent negative headlines may delay price increases. We now assume no additional menu pricing in 2018," wrote West, who added that ongoing challenges could also force it to trim plans for new restaurant openings.
On Tuesday, the Loudoun County Health Department said a second person tested positive for Norovirus after dining at the Chipotle restaurant in Sterling, Virginia. That restaurant was briefly closed last week for a deep cleaning.
The formerly high-flying and fast-growing chain will report second quarter results after the market close on Tuesday. (Reporting by Lisa Baertlein in Los Angeles; Editing by Frances Kerry)