Chicago’s Department of Public Health had identified 55 confirmed infections stemming from the outbreak at an Avondale taqueria, Carniceria Guanajuato, at 3140 N. California Ave., up from 20 last week.

At least 17 people have been hospitalized as of Friday.

An investigation into the source of the bacteria is ongoing. The restaurant remains closed as owners work with public officials to bring the eatery up to safety standards.

Carniceria Guanajuato was inspected September 8th after reports of food poisoning. City health inspectors found raw beef and raw shelled eggs stored above ready-to-eat lettuce and improper storage of hot and cold foods, among other violations. City officials gave guidance on safe food handling practice and proper cleaning to stop the spread, officials said. The restaurant was inspected again September 14th. Inspectors instructed restaurant owners to clean and sanitize certain food preparation areas, install working thermometers inside restaurant coolers, and correct labeling of prepared foods.

Anyone who bought food from the taqueria or from the prepared food section of the grocery store should throw it away and not eat it. People who ate at the taqueria or bought prepared food from the grocery since August 29th could also be exposed.

City officials have alerted local doctors about what to do if people come in showing symptoms of infection, officials said.

An infection can take between six hours and six days to develop. Symptoms from the bacterial infection usually last between four and seven days, and most people recover without treatment, public health officials said.

Older people or those with weakened immune systems can be more impacted. Symptoms include severe diarrhea, dehydration and high fever. Anyone experiencing symptoms should seek medical attention.

Anyone who developed a diarrheal illness after eating food from the restaurant is asked to contact the city’s public health department at to file a suspected food poisoning complaint.