Public health investigators are using the PulseNet system to identify illnesses that may be part of this outbreak. PulseNet is the national subtyping network of public health and food regulatory agency laboratories coordinated by CDC. DNA fingerprinting is performed on Salmonella bacteria isolated from ill people by using techniques called pulsed-field gel electrophoresis (PFGE) and whole genome sequencing (WGS). CDC PulseNet manages a national database of these DNA fingerprints to identify possible outbreaks. WGS gives a more detailed DNA fingerprint than PFGE.
As of June 7, 2018, 60 people infected with the outbreak strain of Salmonella Adelaide have been reported from five states. A list of the states and the number of cases in each can be found on the Case Count Map page.
Illnesses started on dates ranging from April 30, 2018, to May 28, 2018. Ill people range in age from less than 1 year to 97, with a median age of 67. Sixty-five percent are female. Out of 47 people with information available, 31 (66%) have been hospitalized. No deaths have been reported.
Illnesses that occurred after May 20, 2018, might not yet be reported due to the time it takes between when a person becomes ill and when the illness is reported. This takes an average of 2 to 4 weeks. Please see the Timeline for Reporting Cases of Salmonella Infection for more details.
Investigation of the Outbreak
Epidemiologic and preliminary traceback evidence indicates that pre-cut melon supplied by the Caito Foods, LLC of Indianapolis, Indiana is a likely source of this multistate outbreak.
In interviews, ill people answered questions about the foods they ate and other exposures in the week before they became ill. Twenty-five (64%) of 39 people interviewed reported eating pre-cut melon purchased from grocery stores, including cantaloupe, watermelon, or a fruit salad mix with melon. An additional seven people reported consuming melons but did not specify if it was pre-cut.
Information collected from stores where ill people shopped indicates that Caito Foods, LLC supplied pre-cut melon to these stores. On June 8, 2018, Caito Foods, LLC recalled fresh cut watermelon, honeydew melon, cantaloupe, and fresh-cut fruit medley products containing one of these melons produced at the Caito Foods facility in Indianapolis, Indiana.
CDC will provide updates when more information is available