Investigation Details
CDC, public health and regulatory officials in several states, and the U.S. Food and Drug Administration (FDA) investigated a multistate outbreak of Listeria monocytogenes infections.
Epidemiologic, laboratory, and traceback data showed that ice cream made by The Ice Cream House of Brooklyn, NY, made people sick.
As of October 26, 2023, this outbreak is over.
Epidemiologic Data
Two people infected with the outbreak strain of Listeria were reported from two states: one from New York and one from Pennsylvania (see map). Sick people’s samples were collected in May and June 2023 (see timeline). Both sick people were hospitalized, and neither died.
The true number of sick people in this outbreak is likely higher than the number reported, and this outbreak may not have been limited to the states with known illnesses. This is because some people recover without medical care and are not tested for Listeria.
Public health officials collected many different types of information from sick people, including their age, race, ethnicity, other demographics, and the foods they ate in the month before they got sick. This information provided clues to help investigators identify the source of the outbreak.
The table below has information about sick people in this outbreak (“n” is the number of people with information available for each demographic).
| Demographics | Information |
|---|---|
| Age (n=2) |
Median age of 77 years |
| Sex (n=2) |
50% Female 50% Male |
| Race (n=1) |
100% White |
| Ethnicity (n=2) |
100% non-Hispanic |
State and local public health officials from Pennsylvania and New York interviewed people (or their family) about the foods they ate in the month before they got sick. One sick person bought “Soft Serve On The Go” ice cream cups from a grocery store, and the other person likely ate the same ice cream cup at a long-term care facility they were living in.
Laboratory and Traceback Data
Public health investigators used the PulseNet system to identify illnesses that were part of this outbreak. CDC PulseNet manages a national database of DNA fingerprints of bacteria that cause foodborne illnesses. DNA fingerprinting is performed on bacteria using a method called whole genome sequencing (WGS).
WGS showed that bacteria from sick people’s samples were closely related genetically. This suggests that people in this outbreak got sick from the same food.
Pennsylvania Department of Agriculture found the outbreak strain of Listeria in an unopened “Soft Serve On The Go” vanilla chocolate ice cream cup that the sick person had in their freezer. The ice cream tested was purchased after their illness started, but the person bought and ate the same brand and flavor of ice cream several times before getting sick.
The New York State Department of Agriculture and Markets found the outbreak strain of Listeria in five “Soft Serve On The Go” ice cream cups that were collected from the manufacturing location.
The New York City Department of Health and Mental Hygiene found the outbreak strain of Listeria in an “Ice Cream House” mini dessert cigar novelty ice cream product and several environmental samples taken from two of The Ice Cream House stores.
“Ice Cream House” products and “Soft Serve On The Go” ice cream cups were made at the same facility, at The Ice Cream House of Brooklyn, NY.
Public Health Actions
On August 9, 2023, Real Kosher Ice Cream recalled all flavors of “Soft Serve On The Go” ice cream cups.
On August 30, 2023, The Ice Cream House recalled all their dairy ice cream and non-dairy frozen dessert products with the “Ice Cream House” logo.
Epidemiologic, traceback, and laboratory data show that ice cream made at The Ice Cream House of Brooklyn, NY, has made people sick.
Laboratory and Traceback Data
The New York City Department of Health and Mental Hygiene found the outbreak strain of Listeria in an “Ice Cream House” mini dessert cigar novelty ice cream product and several environmental samples taken from The Ice Cream House. “Ice Cream House” products and “Soft Serve On The Go” ice cream cups are made at the same facility.
Public Health Action
On August 30, 2023, The Ice Cream House recalled all their dairy ice cream and non-dairy frozen dessert products with the “Ice Cream House” logo. Do not eat, sell, or serve recalled products.
Epidemiologic, traceback, and laboratory data show that “Soft Serve On The Go” ice cream cups have made people sick.
Laboratory Data
The outbreak strain of Listeria was found in “Soft Serve On The Go” ice cream cups.
The Pennsylvania Department of Agriculture found the outbreak strain of Listeria in an unopened “Soft Serve On The Go” vanilla chocolate ice cream cup that the sick person had in their freezer.
The New York State Department of Agriculture and Markets found the outbreak strain of Listeria in five “Soft Serve On The Go” ice cream cups that were collected from Real Kosher Ice Cream’s manufacturing location.
CDC, public health and regulatory officials in several states, and the U.S. Food and Drug Administration (FDA) are collecting different types of data to investigate a multistate outbreak of Listeria monocytogenes infections.
Epidemiologic and traceback data show that “Soft Serve On The Go” ice cream cups have made people sick.
Epidemiologic and Traceback Data
As of August 10, 2023, two people infected with the outbreak strain of Listeria have been reported from two states: one from New York and one from Pennsylvania (see map). Sick people’s samples were collected in May and June 2023 (see timeline). Both sick people have been hospitalized, and neither died.
The true number of sick people in this outbreak is likely higher than the number reported, and the outbreak may not be limited to the states with known illnesses. This is because some people recover without medical care and are not tested for Listeria. In addition, recent illnesses may not yet be reported as it usually takes 3 to 4 weeks to determine if a sick person is part of an outbreak.
Public health officials collect many different types of information from sick people, including their age, race, ethnicity, other demographics, and the foods they ate in the month before they got sick. This information provides clues to help investigators identify the source of the outbreak.
The table below has information about sick people in this outbreak (“n” is the number of people with information available for each demographic).
| Demographics | Information |
|---|---|
| Age (n=2) |
Median age of 77 years |
| Sex (n=2) |
50% Female 50% Male |
| Race (n=1) |
100% White |
| Ethnicity (n=2) |
100% non-Hispanic |
State and local public health officials from Pennsylvania and New York interviewed people (or their family) about the foods they ate in the month before they got sick. One sick person bought “Soft Serve On The Go” ice cream cups from a grocery store, and the other person likely ate the same ice cream cup at a long-term care facility they were living in.
Laboratory Data
Public health investigators are using the PulseNet system to identify illnesses that may be part of this outbreak. CDC PulseNet manages a national database of DNA fingerprints of bacteria that cause foodborne illnesses. DNA fingerprinting is performed on bacteria using a method called whole genome sequencing (WGS).
WGS showed that bacteria from sick people’s samples are closely related genetically. This suggests that people in this outbreak got sick from the same food.
Pennsylvania Department of Agriculture found Listeria in an unopened “Soft Serve On The Go” vanilla chocolate ice cream cup that the sick person had in their freezer. The ice cream tested was purchased after their illness started, but the person bought and ate the same brand and flavor of ice cream several times before getting sick. WGS is currently being done to see if the Listeria in the ice cream is closely related to the Listeria from sick people.
Public Health Actions
On August 9, 2023, Real Kosher Ice Cream recalled all flavors of “Soft Serve On The Go” ice cream cups. Do not eat, sell, or serve recalled ice cream.
