In July 2011, the Minnesota Department of Health (MDH) Public Health Laboratory (PHL) identified four Salmonella Newport isolates with indistinguishable pulsed-field gel electrophoresis (PFGE) patterns (JJPX1.0011). On routine interview, all four cases reported eating at Sandwich Restaurant Chanin A at 7 locations during the week before illness onset. North Dakota (n=2) and other states reported cases with this pattern which is common through the southeastern US.

The Minnesota and North Dakota cases were enrolled in a case-control study. These cases reported illness onset dates from June 21 to July 4, 2011. One case was hospitalized. No one died. All reported Chain A exposure, with meal dates from June 16 to June 30. Cases were significantly more likely to have eaten at Chain A than controls (6 of 6 cases vs. 4 of 19 controls; matched odds ratio, 8.6; 95% confidence interval, 1.5 to 49.6; p=0.002). Specific items most frequently consumed at Chain A included cucumbers (6 of 6), lettuce (5 of 6), and tomatoes (4 of 6).

Traceback of produce items received at the restaurants from which these six cases purchased meals
revealed that lettuce was provided by multiple west-coast suppliers and therefore was unlikely to be
a common vehicle for S. Newport in this outbreak. Cucumbers or tomatoes could have come from a
common source. However, a single definite source could not be distinguished from the available data.