Twenty three people in 7 states and the District of Columbia were diagnosed with Salmonella Bovismorbificans between August 19 and November 21, 2011. Median age was 27 (age range 20-87). Among the 22 patients with exposure information, 20 (91%) reported eating at restaurants in the DC metropolitan area. Sixteen of 19 patients reported eating Mediterranean-style food; 10 of 15 patients reported eating hummus. All 23 patients received outpatient medical care. No hospitalizations or deaths were reported.

District of Columbia health investigators collected hummus and hummus ingredients from 2 restaurants. The DC Public Health Laboratory isolated S. Bovismorbificans from hummus samples which was a genetic match to the strain isolated in case patients. On May 30, 2012 traceback by FDA suggested that tahini used in hummus was a plausible source of the contaminated hummus. The traceback revealed tahini used at the different restaurants in the DC area came from a common foreign manufacturer from Lebanon associated with recent Salmonella outbreaks in Canada.