Be First, Be Right, Be Credible: Using Risk Communication Principles in Practice to Reassure and Advise Consumers during Foodborne Outbreaks

Background:

As the nation’s public health agency, CDC investigates and responds to multistate foodborne outbreaks of infections like E. coli. During foodborne outbreaks, the public looks to credible, trustworthy sources of information for advice to protect themselves.

When deciding to communicate, acting quickly to prevent additional illnesses should be balanced with issuing the right message - the wrong message could negatively affect the health of the public. CDC developed web postings to quickly issue public warnings when investigators identified the specific food making people sick and could advise the public accordingly.

Program background: From December 2017 through January 2019, CDC issued multiple public warnings during three separate multistate outbreaks of E. coli O157:H7 infections linked to romaine lettuce or other leafy greens.

Evaluation Methods and Results:

On December 21, 2017, Canadian health officials advised Canadian consumers to avoid romaine lettuce after linking an outbreak of E. coli infections to romaine lettuce. CDC identified illnesses in the United States with the same strain of E. coli, but the U.S. investigation was unable to identify a specific type of leafy green. The existing public warning template did not offer a way to share investigation details without providing specific advice about what foods to avoid. Needing to communicate quickly without specific advice, CDC issued a brief media statement describing the investigation. This led to confusion, extensive media inquiries, and conflicting advice offered from non-CDC sources.

Subsequently, CDC created two separate templates: an Investigation Notice, for use early in investigations without a specific food source identified; and a Food Safety Alert, for use when a specific food source was identified. These two templates, developed with input from the CDC User Experience Team, gave CDC more flexibility when deciding how and when to communicate during these often complex and nuanced outbreak investigations.

In April 2018, CDC used an Investigation Notice to communicate early about a rapidly-growing outbreak of E. coli infections that did not yet have a source identified. Within three days, CDC issued a Food Safety Alert warning consumers not to eat romaine lettuce from a particular harvest region. This advice was specific but not actionable given that romaine lettuce packaging does not include this level of detail. Again, this communication method led to confusion, extensive media inquiries, and conflicting advice offered from non-CDC sources.

In November 2018, CDC identified yet another outbreak of E. coli infections linked to romaine lettuce. A Food Safety Alert advised the public to not eat any romaine lettuce, regardless of where it was grown, until more information was available. Although there were extensive media inquiries, this broad warning was much less confusing and did not result in conflicting advice from non-CDC sources.

Conclusions: Three outbreaks of E. coli infections were linked to romaine lettuce or other leafy greens within 15 months, leading CDC to reevaluate the way it communicates. This process required a culture shift toward sharing information earlier in an investigation.

Implications for research and/or practice: Public communication models need to be based on risk communication principles while being flexible enough to adapt to the changing landscape of increasing transparency.