At least 196 patrons and four employees of Las Vegas tapas restaurant Firefly have fallen ill in the Salmonella outbreak health officials have called Nevada’s worst outbreak of the past decade, according to a report released Friday morning by the Southern Nevada Health District. The outbreak sickened diners from 20 U.S. states, along with Canada and the United Kingdom. Both Firefly on Paradise Ave. and neighboring restaurant Dragonfly, which shares kitchen facilities, have been closed since April 26 after the health district received reports of eight separate groups of patrons experienced illness. A health inspection at the establishment cited 44 demerits for Firefly and 47 for Dragonfly, including improper cooling practices, holding temperatures and storing of potentially hazardous foods that included “raw animal products” being stored above ready-to-eat foods. Health investigators confirmed 16 of the cases through laboratory analysis to have been infected with Salmonella serotype I:4,5,12:i:-. Three of the confirmed cases were employees, each of whom consumed food at the restaurant and experienced illness onset timing showing they were not the source of the outbreak. No new illnesses have been reported since May 1. In a written statement to the community, Firefly owner John Simmons said there were no plans to reopen Firefly at the closed location, but would instead move the restaurant to a new building on the same street. “Firefly has been a proud member of Southern Nevada for 10 years and we are optimistic that the combination of moving to this new location, that has a kitchen as large as the entire original Firefly restaurant, and the recommended retraining on operations and procedures, will help us regain the confidence of the community,” Simmons said. Health investigators could not pinpoint a specific food item as the source, though ill patrons were much more likely to eat certain menu items when compared to patrons who didn’t fall ill in a case-control study. The investigation initially looked at Firefly’s unpasteurized egg-based aioli sauce because of the number of ill patrons who reported eating it, but further analysis showed it was not the cause. Specific ingredients such as parsley and grated hard cheese underwent additional scrutiny but were not shown to be a likely source. Inspectors visited two other Firefly establishments in Clark County and did not find evidence of Salmonella contamination. One location, on Eastern Ave. in Henderson, received an ‘A’ rating following its inspection. The other, on Sahara Ave. in Las Vegas, was cited for 30 demerits, which were found to be corrected in a follow-up inspection. Health officials are still performing laboratory analysis on a number of individual food items in an effort to identify an outbreak source. Three Salmonella samples have also been sent to a federal lab to test for antimicrobial resistance. Those sickened in the outbreak included travelers from the following 20 states: AZ, CA, CO, HI, IL, MA, MN, MS, NC, NE, NV, NY, OH, OK, OR, PA, SC, TX, UT, and WA. Salmonella serotype I:4,5,12:i:- is a variant of Salmonella Typhimurium most notably associated with a 2007 outbreak associated with Banquet pot pies that sickened at least 401 people.