Worthy Burger restaurant in South Royalton. The restaurant voluntarily closed for five days in late September, saying the decision was based on "mechanical reasons," although it coincided with the department's investigation. Reportedly, Worthy Burger has changed its vendors because of recommendations from health officials after the E. coli outbreak. The health department also recommended Worthy Burger ensures that its hamburgers are cooked to 155°F as measured with a food thermometer and held at that temperature for at least 15 seconds. The restaurant also was instructed to undergo a thorough cleaning.