April 16, 2018

CDC, public health and regulatory officials in several states, and the U.S. Food and Drug Administration (FDA) are investigating a multistate outbreak of Salmonella Braenderup infections.

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 April 16, 2018, 23 people infected with the outbreak strain of Salmonella Braenderup have been reported from 9 states. A list of the states and the number of cases in each can be found on the Case Count Map page. WGS performed on bacteria isolated from ill people showed that they were closely relatedly genetically. This means that people in this outbreak are more likely to share a common source of infection.

Illnesses started on dates ranging from November 16, 2017, to March 22, 2018. Ill people range in age from 5 to 90, with a median age of 65. Fifty-five percent are male. Six people have been hospitalized, and no deaths have been reported.

This outbreak can be illustrated with a chart showing the number of people who became ill each day. This chart is called an epidemic curve, or epi curve. Illnesses that occurred after February 25, 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 two to four weeks. Please see the Timeline for Reporting Cases of Salmonella Infection for more details.

WGS analysis did not predict antibiotic resistance in isolates from 14 ill people. Standard antibiotic resistance testing by CDC’s National Antimicrobial Resistance Monitoring System (NARMS) laboratory is currently underway.

Investigation of the Outbreak

Epidemiologic, laboratory, and traceback evidence indicates that shell eggs produced by Rose Acre Farms are the 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. Seventeen (100%) of 17 people interviewed reported eating shell eggs. Eleven (65%) reported eating various egg dishes at different restaurants. This percentage is significantly higher than results from a survey [787 KB] of healthy people in which 38% of respondents reported eating any eggs away from home in the week before they were interviewed. These restaurants reported using shell eggs in the dishes eaten by ill people.

FDA traced the source of some of the shell eggs supplied to these restaurant locations to Rose Acre Farms’ Hyde County, North Carolina farm. FDA investigators inspected the farm and collected samples for testing. Laboratory testing identified the outbreak strain of Salmonella Braenderup in environmental samples taken at the farm.

On April 13, 2018, Rose Acre Farms of Seymour, Indiana, voluntarily recalled 206,749,248 shell eggs because they could be contaminated with Salmonella bacteria. Recalled eggs were sold in grocery stores and to restaurants in Colorado, Florida, New Jersey, New York, North Carolina, Pennsylvania, South Carolina, Virginia, and West Virginia under multiple brand names, including Coburn Farms, Country Daybreak, Crystal Farms, Food Lion, Glenview, Great Value, Nelms, and Sunshine Farms.

This investigation is ongoing and we will provide updates when they are available.