Shares of Chipotle Mexican Grill declined as much as 2 percent Friday morning after The Post reported the chain’s food safety issues have persisted longer than previously believed.

The Denver-based burrito chain has been sickening customers across the country as far back as July, resulting in scores of diners contracting norovirus, salmonella and E. coli well before the headline-grabbing, nine-state outbreak in October and November.

Some local health departments that were stung by an outbreak at Chipotle restaurants are taking an even harder look at the 1,900-store chain in an effort to be proactive.

The Seattle public health department, which includes King County, closed a Chipotle store on Thursday that had been shut down once before during the fall outbreak.

The agency has been visiting the 20-plus stores in its district more frequently and found the temperature was too low for the chicken and beef at the 212 Westlake Ave. location — the most severe violation and the third time that store had done so in 12 months. It also kept brown rice and vegetables at a too low temperature.

The agency acknowledged that the point total in violations would not ordinarily result in a restaurant’s closure, but that it was the third time that Chipotle was in violation of health standards for safe food handling.