Public health officials in San Francisco are investigating a number of complaints of foodborne illness among patrons of the House of Prime Rib restaurant.

Since March 31 the San Francisco Department of Public Health has received six complaints, according to a statement sent to Food Safety News today. Some complaints represent more than one sick person if multiple people are from a single household.

“In addition, just today, the DPH Communicable Disease Control Unit (CDCU) received four reports of a foodborne illness with a total of 12 individuals alleging that they became ill and developed symptoms, specific to this facility,” the public health statement says.

“CDCU counts multiple complaints as one official complaint when complainants reside in the same home.) As a result, CDCU will be conducting more epidemiological-based interviews with the complainants. once the full interviews are complete, CDCU will provide the gathered information to DPH Environmental Health (EH) to conduct their onsite investigation.”

The outbreak investigation comes a month after a similar situation, according to the public health department. Some of the investigation details from that episode are not being released because of “protected health information.”

“EH conducted an onsite inspection that was largely shaped and directed by the information gathered from those interviews on April 7, 2021,” the health department reports. “The EH inspection did not reveal any major violations.  Lower risk violations were observed, that have since been corrected, e.g. faster cleaning and sanitizing response time to the build-up of food debris on mechanical equipment.

“At this point in time, the current investigation is ongoing. DPH is responding accordingly and will take further additional steps if epidemiological information suggests a link between the practices of the restaurant in question and the recent alleged foodborne illness complaints.”

The website iwaspoisoned.com has reports of dozens of people becoming ill after eating at the restaurant. In the past 14 days, the website has received 35 reports citing 86 people sick, according to site founded Patrick Quade.