2019 Outbreak of Listeria Infections Linked to Unknown Source – Timeline

Final Update

Posted November 7, 2019 at 1:00 PM ET

This outbreak appears to be over. CDC, several states, and federal partners investigated a multistate outbreak of Listeria monocytogenes infections. A single, common source of infections was not identified. Learn more about how you can take steps to prevent Listeria infection.

People infected with the outbreak strain of Listeria monocytogenes, by month of isolation*

Epi curve of people infected with the outbreak strain of Listeria, by date of illness onset, as of November 7, 2019.

*n=24 for whom information was reported as of November 7, 2019.

Previous Timelines

People infected with the outbreak strain of Listeria monocytogenes, by date of isolation*

Epi curve of people infected with the outbreak strain of Listeria, by date of illness onset, as of August 22, 2019.

*n=24 for whom information was reported as of August 23, 2019.

Read the full Investigation Notice