Officials believe that an outbreak of norovirus is responsible for sickening dozens of patrons at a Ventura County Chipotle restaurant earlier this month.
The Ventura County Environmental Health Division began investigating last week after more than 60 customers became ill after eating at the burrito chain's Simi Valley Towne Center location.
Officials now say about 80 customers and 18 employees ultimately became ill with gastrointestinal symptoms during the week of Aug. 18.
Managers shut down the restaurant Friday, Aug. 21, threw out all remaining food and disinfected all surfaces, according to health officials. It reopened the next morning, health officials say, but managers told the 18 employees who had been sickened to stay home.
During an inspection last week and a follow-up inspection Sunday, investigators found some violations, including dirty restrooms; unclean utensils or equipment; equipment connected to sewer lines; unsanitary floors, walls or ceilings; and insufficient food temperatures. Some workers also did not have valid food handler cards.
Despite those violations, the restaurant passed both inspections.
So far, eight out of 18 samples submitted by Chipotle employees have tested positive for norovirus, according to Mike Byrne of the Ventura County Environmental Health Division.
Employees who have tested positive for norovirus will be restricted from food service duties until tests come back negative, Byrne said.
There have been no other reports of illness since that week.
Byrne says investigators have not determined exactly what food or contact caused the apparent norovirus outbreak. "We may never know what caused it in the end," Byrne said. "We're focused on making sure there are no other illnesses going forward."
Norovirus is a particularly contagious bug that causes inflammation of the stomach or intestines, leading to stomach pain, nausea, diarrhea and vomiting.
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