Multistate Outbreak of Shiga toxin-producing Escherichia coli O157:H7 Infections Linked to I.M. Healthy Brand SoyNut Butter (Final Update)

Posted May 4, 2017 11:45 AM EST

Although the outbreak investigation is over, illnesses may continue for some time. The recalled SoyNut Butter products have long shelf lives and may still be in people’s homes or in institutions. People who don’t know about the recalls could continue to eat the products and get sick. The recalled products are listed on the Recalls & Advice to Consumers page.

Highlights

Although the outbreak investigation is over, illnesses may continue for some time. The recalled SoyNut Butter products have long shelf lives and may still be in people’s homes or in institutions. People who don’t know about the recalls could continue to eat the products and get sick.
Several products were recalled as a result of this investigation.
- The recalled products are listed on the Recalls & Advice to Consumers page.
- CDC recommends that consumers do not eat, and childcare centers, schools, and other institutions do not serve, any of the recalled products.
- Even if some of the product was eaten or served and no one got sick, throw the rest of it away. Put it in a sealed bag in the trash so that children, pets, or other animals can’t eat it.
CDC, multiple states, and the U.S. Food and Drug Administration (FDA) investigated a multistate outbreak of Shiga toxin-producing Escherichia coliO157:H7 (STEC O157:H7) infections.
- Thirty-two people infected with the outbreak strains of STEC O157:H7 were reported from 12 states.
- Twelve people were hospitalized. Nine people developed hemolytic uremic syndrome, a type of kidney failure. No deaths were reported.
- Twenty-six (81%) of the 32 ill people in this outbreak were younger than 18 years.
Epidemiologic, laboratory, and traceback evidence indicated that I.M. Healthy brand SoyNut Butter was the likely source of this outbreak.

Outbreak Summary

Introduction

CDC collaborated with public health and regulatory officials in many states and the U.S. Food and Drug Administration (FDA) to investigate a multistate outbreak of Shiga toxin-producing Escherichia coli (STEC) infections.

Public health investigators used the PulseNet system to identify illnesses that might be part of this outbreak. Thirty-two people infected with the outbreak strains of STEC O157:H7 were reported from 12 states. A list of the states and the number of cases in each can be found on the Case Count Map page. Whole genome sequencing (WGS) performed on clinical isolates from ill people showed that the isolates were closely related genetically. This close genetic relationship provided more evidence that people in this outbreak became ill from a common source.

Illnesses started on dates ranging from January 4, 2017 to April 18, 2017. Ill people ranged in age from 1 to 70 years, with a median age of 9. Twenty-six (81%) of the 32 ill people were younger than 18 years. Among ill people, 59% were male. Twelve ill people were hospitalized, and 9 people developed hemolytic uremic syndrome, a type of kidney failure. No deaths were reported.

Investigation of the Outbreak

Epidemiologic, laboratory, and traceback evidence indicated that I.M. Health brand SoyNut Butter was the likely source of this outbreak. SoyNut Butter is a nut-free substitute for peanut butter.

In interviews, ill people or their family members answered questions about the foods they ate and other exposures in the week before they became ill. Twenty-five (78%) of the 32 people reached for interview reported either eating I.M. Healthy brand SoyNut Butter at home (19 people) in the week before they became ill, attending a facility that served I.M. Healthy brand SoyNut Butter (2 people), or attending childcare centers that served I.M. Healthy brand SoyNut Butter and I.M. Healthy brand granola coated with SoyNut Butter (4 people).

Investigators reported to CDC two more ill people who either developed HUS or had a diagnostic test showing they were infected with STEC bacteria. In interviews, both of these ill people reported eating I.M. Healthy brand SoyNut Butter in the week before becoming ill. However, CDC did not include these people in the outbreak case count because no bacterial isolates, or samples, were available for DNA fingerprinting. Public health investigators use DNA fingerprinting to identify illnesses that are part of multistate outbreaks.

Laboratory testing identified STEC O157:H7 in opened containers of I.M. Healthy brand SoyNut Butter collected from the homes of ill people in California, Oregon, and Washington. Officials in California also isolated STEC O157:H7 in unopened containers of I.M. Healthy brand SoyNut Butter collected from retail locations. WGS showed that the STEC O157:H7 in all of these containers of SoyNut Butter were closely related genetically to isolates from ill people, providing more evidence that people in this outbreak got sick from eating I.M. Healthy brand SoyNut butter.

Although the outbreak investigation is over, illnesses may continue for some time. The recalled SoyNut Butter products have long shelf lives and may still be in people’s homes or in institutions. Consumers who don’t know about the recalls could continue to eat the products and get sick. The recalled products are listed on the Recalls & Advice to Consumers page.

March 30, 2017

Case Count Update

Since the last update on March 21, 2017, six more ill people have been reported from four states.

Twenty-nine people infected with the outbreak strains of STEC O157:H7 have been reported from 12 states. A list of the states and the number of cases in each can be found on the Case Count Map page.

Illnesses started on dates ranging from January 4, 2017, to March 13, 2017. Ill people range in age from 1 to 57 years, with a median age of 8. Twenty-four (83%) of the 29 ill people are younger than 18 years. Among ill people, 59% are male. Twelve ill people have been hospitalized, and nine people developed hemolytic uremic syndrome, a type of kidney failure. No deaths have been reported.

Illnesses that occurred after March 7, 2017, 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 2 to 3 weeks. Please see the Timeline for Reporting Cases of E. coli O157:H7 Infection for more details.

Investigation Update

In interviews, ill people or their family members answered questions about the foods they ate and other exposures in the week before they became ill. Twenty-one (75%) of the 28 people reached for interview reported either eating I.M. Healthy brand SoyNut Butter at home (15 people) in the week before they became ill, attending a facility that served I.M. Healthy brand SoyNut Butter (2 people), or attending childcare centers that served I.M. Healthy brand SoyNut Butter and I.M. Healthy brand granola coated with SoyNut Butter (4 people).

The investigation is ongoing. CDC will update the public when more information becomes available.

March 21, 2017

Case Count Update

Since the last update on March 13, 2017, seven more ill people have been reported from four states.

Twenty-three people infected with the outbreak strains of STEC O157:H7 have been reported from nine states. A list of the states and the number of cases in each can be found on the Case Count Map page.

Illnesses started on dates ranging from January 4, 2017, to March 5, 2017. Ill people range in age from 1 to 48 years, with a median age of 8. Twenty (87%) of the 23 ill people are younger than 18 years. Among ill people, 61% are male. Ten ill people have been hospitalized and seven people developed hemolytic uremic syndrome (HUS), a type of kidney failure. No deaths have been reported.

Illnesses that occurred after February 24, 2017, 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 2 to 3 weeks. Please see the Timeline for Reporting Cases of E. coli O157:H7 Infection for more details.

Investigation Update

In interviews, ill people or their family members answered questions about the foods they ate and other exposures in the week before they became ill. Twenty (87%) of the 23 people reached for interview reported either eating I.M. Healthy brand SoyNut Butter at home (14 people) in the week before they became ill, attending a facility that served I.M. Health brand SoyNut Butter (2 people), or attending childcare centers that served I.M. Healthy brand SoyNut Butter and I.M. Healthy brand granola coated with SoyNut Butter (4 people). SoyNut Butter is a nut-free substitute for peanut butter.

Investigators have reported to CDC two more ill people who either developed HUS or had a diagnostic test showing they were infected with STEC bacteria. In interviews, both of these ill people reported eating I.M. Healthy brand SoyNut Butter in the week before becoming ill. However, CDC is not including these people in the outbreak case count because no bacterial isolates, or samples, were available for DNA fingerprinting. Public health investigators use DNA fingerprinting to identify illnesses that are part of outbreaks.

Laboratory testing identified STEC O157:H7 in opened containers of I.M. Healthy brand SoyNut Butter collected from the homes of ill people in California, Oregon, and Washington. Officials in California also isolated STEC O157:H7 in unopened containers of I.M. Healthy brand SoyNut Butter collected from retail locations. Further testing using pulsed-field gel electrophoresis (PFGE) showed that the STEC O157:H7 in all of these containers of SoyNut Butter had the same DNA fingerprints as the STEC O157:H7 isolates from ill people.

The investigation is ongoing. CDC will update the public when more information becomes available.

March 7, 2017

Case Count Update

Since the last update on March 3, 2017, four more ill people have been reported from four states.

Sixteen people infected with the outbreak strain of STEC O157:H7 have been reported from nine states. A list of the states and the number of cases in each can be found on the Case Count Map page.

Illnesses started on dates ranging from January 4, 2017 to February 21, 2017. Ill people range in age from 2 to 48 years, with a median age of 10. Fourteen (88%) of the 16 ill people are younger than 18 years old. Among ill people, 63% are male. Eight ill people have been hospitalized and five people developed hemolytic uremic syndrome, a type of kidney failure. No deaths have been reported.

Illnesses that occurred after February 13, 2017, 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 2 to 3 weeks. Please see the Timeline for Reporting Cases of E. coli O157:H7 Infection for more details.

Investigation Update

In interviews, ill people or their family members answered questions about the foods they ate and other exposures in the week before they became ill. Fifteen (100%) of the 15 people reached for interview reported either eating I.M. Healthy brand SoyNut Butter at home (nine people) in the week before they became ill, attending a facility that served I.M. Health brand SoyNut Butter (two people), or attending childcare centers that served I.M. Healthy brand SoyNut Butter and I.M. Healthy brand granola coated with SoyNut Butter (four people).

Initial Announcement

March 3, 2017

CDC is collaborating with public health and regulatory officials in several states and the U.S. Food and Drug Administration (FDA) to investigate a multistate outbreak of Shiga toxin-producing Escherichia coli O157:H7 (STEC O157:H7) infections.

Public health investigators are using the PulseNet system to identify illnesses that may be part of this outbreak. PulseNet, coordinated by CDC, is the national subtyping network of public health and food regulatory agency laboratories. PulseNet performs DNA fingerprinting on STEC 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. In this outbreak, the outbreak strain was defined by PFGE. The DNA fingerprint of the outbreak strain has never been seen before in the PulseNet database.

Twelve people infected with the outbreak strain of STEC O157:H7 have been reported from five states. A list of the states and the number of cases in each can be found on the Case Count Map page.

Illnesses started on dates ranging from January 6, 2017 to February 15, 2017. Ill people range in age from 2 to 48 years, with a median age of 8. Eleven (92%) of the 12 ill people are younger than 18 years old. Among ill people, 58% are male. Six ill people have been hospitalized and four people developed hemolytic uremic syndrome, a type of kidney failure. 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 8, 2017 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 2 to 3 weeks. Please see the Timeline for Reporting Cases of E. coli O157:H7 Infection for more details.

Investigation of the Outbreak

Epidemiologic evidence available at this time indicates that I.M. Healthy brand SoyNut Butter is a likely source of this outbreak. SoyNut Butter is a nut-free substitute for peanut butter.

In interviews, ill people or their family members answered questions about the foods they ate and other exposures in the week before they became ill. Nine (100%) of the nine people reached for interview reported either eating I.M. Healthy brand SoyNut Butter at home (five people) in the week before they became ill or attending a childcare center that served I.M. Healthy brand SoyNut Butter or I.M. Healthy brand granola coated with SoyNut Butter (four people). This proportion is significantly higher than expected when compared to the approximately 6% of ill people interviewed during past outbreak investigations who reported eating a ground nut butter or spread other than peanut butter.

I.M. Healthy brand SoyNut Butter may be contaminated with E. coli O157:H7 and could make people sick. CDC recommends consumers do not eat any I.M. Healthy brand SoyNut Butter varieties or sizes or I.M. Healthy brand granola coated with SoyNut Butter. Childcare centers, schools, and other institutions should not serve I.M. Healthy brand SoyNut Butter or I.M. Healthy brand granola coated with SoyNut Butter. Multiple varieties and sizes of I.M. Healthy brand SoyNut butter and I.M. Healthy brand granola coated with SoyNut Butter are sold nationwide in stores, online, and to institutions. The products have a shelf life of 2 years.

This investigation is ongoing and quickly changing. CDC will provide updates when more information is available.