Federal officials are reporting that an outbreak of E. coli O121:H9 infections linked to romaine lettuce has ended.

Four illnesses were confirmed in the outbreak. Little other information was available from the Food and Drug Administration.

“The information collected over the course of this investigation indicated that romaine lettuce was the likely source of this outbreak; however, it appears that this outbreak is over, and there is no actionable advice for consumers,” according to FDA officials.

“FDA has been conducting a traceback investigation and other activities in an effort to learn more about possible sources or routes of contamination.”

The FDA first reported the outbreak two weeks ago but has not shared any information about patient demographics or what states are involved. The agency did not report when the first illness was reported or when the last one was logged by public health officials.

As of Jan. 26, the Centers for Disease Control and Prevention had not posted any information about the outbreak. That is generally standing procedure for the agency if a specific product is not identified.

Romaine and other leafy greens have been behind many foodborne illness outbreaks in recent years. Most involved bagged or otherwise packaged salads. Those outbreaks include:

2018 — E. coli — romaine lettuce
62 people infected with the outbreak strain of E. coli O157:H7 were reported from 16 states and the District of Columbia; 25 patients were hospitalized.
Canada also identified patients infected with the outbreak strain. 

2018 – Cyclospora — romaine lettuce-carrot mix in McDonalds salad
511 infections were confirmed in people from 15 states.

2018 — E. coli — romaine lettuce
210 people infected with the outbreak strain were reported from 36 states; 96 people were hospitalized, including 27 people who developed a type of kidney failure called hemolytic uremic syndrome; 5 deaths were reported.

2018-19 — E. coli — romaine lettuce
167 people infected with the outbreak strain of E. coli O157:H7 were reported from 27 states; 85 hospitalizations were reported, including 15 people who developed hemolytic uremic syndrome, a type of kidney failure.

2020 — E. coli — leafy greens
40 people were infected with the outbreak strain of E. coli O157:H7 from 19 states; 20 were hospitalized.

2020 — Cyclospora — bagged salad
701 people with laboratory-confirmed Cyclospora infections were reported from 14 states; 38 were hospitalized.

2021 — E. coli — packaged salad
10 people infected with the outbreak strain of E. coli O157:H7 were reported from four states; four were hospitalized and one person developed a type of kidney failure called hemolytic uremic syndrome (HUS).

2021 — Listeria — packaged salad
16 people infected with the outbreak strain of Listeria monocytogenes were reported from 13 states; 12 were hospitalized; 2 deaths were reported.

2021 — Listeria — packaged salad
10 people infected with the outbreak strain of Listeria monocytogenes were reported from eight states; all 10 people were hospitalized; 1 death was reported.

2021 — E. coli — baby spinach
15 people infected with the outbreak strain of E. coli O157:H7 were reported from 10 states; 4 were hospitalized and 3 developed a type of kidney failure called hemolytic uremic syndrome (HUS).

2021 — Salmonella — packaged salad
31 people infected with the outbreak strain of Salmonella Typhimurium were reported from 4 states; 4 people were hospitalized.

Additional outbreaks associated with leafy greens included:

Date Vehicle Etiology Confirmed
Cases		 States/Provinces
July 1995 Lettuce (leafy green; red; romaine) E. coli O157:H7 74 1:MT
Sept. 1995 Lettuce (romaine) E. coli O157:H7 20 1:ID
Sept. 1995 Lettuce (iceberg) E. coli O157:H7 30 1:ME
Oct. 1995 Lettuce (iceberg; unconfirmed) E. coli O157:H7 11 1:OH
May-June 1996 Lettuce (mesclun; red leaf) E. coli O157:H7 61 3:CT, IL, NY
May 1998 Salad E. coli O157:H7 2 1:CA
Feb.-Mar. 1999 Lettuce (iceberg) E. coli O157:H7 72 1:NE
Oct. 1999 Salad E. coli O157:H7 92 3:OR, PA, OH
Oct. 2000 Lettuce E. coli O157:H7 6 1:IN
Nov. 2001 Lettuce E. coli O157:H7 20 1:TX
July-Aug. 2002 Lettuce (romaine) E. coli O157:H7 29 2:WA, ID
Nov. 2002 Lettuce E. coli O157:H7 13 1:Il
Dec. 2002 Lettuce E. coli O157:H7 3 1:MN
Oct. 2003-May 2004 Lettuce (mixed salad) E. coli O157:H7 57 1:CA
Apr. 2004 Spinach E. coli O157:H7 16 1:CA
Nov. 2004 Lettuce E. coli O157:H7 6 1:NJ
Sept. 2005 Lettuce (romaine) E. coli O157:H7 32 3:MN, WI, OR
Sept. 2006 Spinach (baby) E. coli O157:H7 and other serotypes 205 Multistate and Canada
Nov./Dec. 2006 Lettuce E. coli O157:H7 71 4:NY, NJ, PA, DE
Nov./Dec. 2006 Lettuce E. coli O157:H7 81 3:IA, MN, WI
July 2007 Lettuce E. coli O157:H7 26 1:AL
May 2008 Romaine E. coli O157:H7 9 1:WA
Oct. 2008 Lettuce E. coli O157:H7 59 Multistate and Canada
Nov. 2008 Lettuce E. coli O157:H7 130 Canada
Sept. 2009 Lettuce: Romaine or Iceberg E. coli O157:H7 29 Multistate
Sept. 2009 Lettuce E. coli O157:H7 10 Multistate
April 2010 Romaine E. coli O145 33 5:MI, NY, OH, PA, TN
Oct. 2011 Romaine E. coli O157:H7 60 Multistate
April 2012 Romaine E. coli O157:H7 28

1:CA

Canada
June 2012 Romaine E. coli O157:H7 52 Multistate
Sept. 2012 Romaine E. coli O157:H7 9 1:PA
Oct. 2012 Spinach and Spring Mix Blend E. coli O157:H7 33 Multistate
Apr. 2013 Leafy Greens E. coli O157:H7 14 Multistate
Aug. 2013 Leafy Greens E. coli O157:H7 15 1:PA
Oct. 2013 Ready-To-Eat Salads E. coli O157:H7 33 Multistate
Apr. 2014 Romaine E. coli O126 4 1:MN
Apr. 2015 Leafy Greens E. coli O145 7 3:MD, SC, VA
June 2016 Mesclun Mix E. coli O157:H7 11 3:IL, MI, WI
Nov. 2017 Leafy Greens E. coli O157:H7 67 Multistate and Canada

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