In April and May of 1998, public health officials in eleven states received an unusually high number of reports that patients receiving health care services for gastrointestinal illness had been diagnosed with Salmonella serotype Agona infections. The number of illnesses represented an eightfold increase over the median number of Salmonella Agona cases reported in those states from 1993 to 1997.
To determine the source of the apparent ongoing Salmonella outbreak, investigators from the states and the Centers for Disease Control and Prevention (CDC) conducted a case-control study comparing individuals who had been diagnosed with Salmonella Agona with well household members. By June 8, 1998, 55 households had been interviewed and investigators learned that a majority of cases had consumed Millville brand plain Toasted Oats cereal before becoming ill.
Testing conducted on Toasted Oats cereal resulted in one positive Salmonella culture from an open box of the cereal and two positive cultures from unopened boxes. The pulsed field gel electrophoresis (PFGE) pattern, or “genetic fingerprint” of the Salmonella Agona isolated from the cereal was indistinguishable from that isolated from human samples. Malt-O-Meal, the manufacturer of the cereal, issued a recall of all plain Toasted Oats cereal.
Ultimately, 209 illnesses were reported to public health officials; 47 were hospitalizations. Salmonella Agona cases associated with consumption of Malt-O-Meal Toasted Oats cereal were reported in California, Connecticut, Idaho, Maryland, Minnesota, Nebraska, New Jersey, Oklahoma, Tennessee, and Washington.
Marler Clark filed a class action lawsuit on behalf of all people who became ill with Salmonella infections after eating the contaminated cereal. Claims against Malt-O-Meal were resolved in 2000.