An E. coli outbreak at the Chicken & Rice Guys restaurant chain has sickened 14 people, including 10 who required hospitalization, Boston public health officials said Wednesday.
The chain, which temporarily closed its four restaurants in Boston and Medford and grounded its fleet of food trucks on Tuesday, likely will not reopen until at least the middle of next week while health officials search for the cause of the outbreak.
City health officials could not answer questions about the status of those who sought hospital treatment. They did not specify whether those hospitalizations continue. The state Department of Public Health, which is also involved in the investigation, referred those questions to the city.
Boston officials initially said the outbreak could be traced to the restaurant’s Allston outpost, but said Wednesday that some people had become ill after eating at one of the food trucks. They did not identify which truck, or when the exposure took place.
William Christopher, commissioner of Boston’s Inspectional Services division, said food at the facility could have become tainted with E. coli on site, through an employee, or it could have arrived from a vendor already contaminated.
“They will remain closed until we get the tests back from public health investigators,” Christopher said. “This may have come from an outside source and this may not be the businesses’ situation. It could be anything.”
Public health departments in Medford and Somerville, where Chicken & Rice Guys operates a commissary, are involved in the investigation, as is the US Centers for Disease Control and Prevention.
E. coli O157:H7, the strain that was identified in the Chicken & Rice Guys, is a potentially deadly bacterium that can cause dehydration, diarrhea, and abdominal cramps two to eight days after exposure. While most people recover within a week, some develop a type of kidney failure called hemolytic uremic syndrome that can be fatal.
Chicken & Rice Guys spokesman Steven Collicelli said the company, which has about 90 employees, closed its restaurants after learning from public health officials that customers had gotten sick. Collicelli said he did not know which of the company’s five food trucks might be to blame. Public health officials told him that some of the illnesses were first reported in late March.
“First and foremost for us is our customers’ safety and health,” he said. “The last thing any restaurant wants is to get their customers’ sick.”
Seattle lawyer William D. Marler, who specializes in cases involving food-borne illness, said the fact that 14 people fell ill is significant, considering that 29 people were sickened nationally in a recent E. coli outbreak connected to soy nut butter. That incident triggered a massive recall.
“This is serious stuff,” Marler said. “This is a nasty, nasty bug that sickens and kills a lot of people.”
E. coli outbreaks can occur if meat is undercooked or a restaurant serves vegetables that are contaminated by the bacteria, which is primarily found in the fecal matter of cattle, he said. It can also be spread from person to person, although that is less common, he said.
In many E. coli investigations, a clear source is not identified, Marler said, because the illness takes several days to make a person sick and by that time much of the food evidence is gone.
At the Chicken & Rice Guys location in Downtown Crossing during Wednesday’s lunch hour, the doors were locked and disappointed would-be customers searched for new lunch options.
One of those customers, Dave Andrews, said he ate there last week and got sick that night.
“I ordered the chicken with lamb and salad,” he said. “It didn’t land very well.”
A few other lunch seekers weren’t fazed by the health scare and said they would return when it reopened.
Quite a few simply walked across the street to dine at Chipotle Mexican Grill, a restaurant that has suffered its own setbacks after a series of food-poisoning outbreaks in 2015.Globe correspondent Shelby Grebbin contributed to this report. Megan Woolhouse can be reached at firstname.lastname@example.org. Follow her on Twitter @megwoolhouse.