Multistate outbreak of multiple Salmonella serotype infections linked to sprouted chia seed powder – United States, 2014

To be presented at the U.S. Centers for Disease Control and Prevention’s 64th Annual Epidemic Intelligence Service (EIS) conference April 20-23 in Atlanta. Salmonella causes 1.2 million infections and 380 deaths annually in the United States. On 5/6/2014, PulseNet, the national molecular subtyping network for foodborne disease surveillance, identified a cluster of Salmonella Newport infections with the same novel outbreak strain. US states, FDA, Canada, and CDC investigated to identify the source and prevent additional illnesses.

Methods: We defined a case as infection with an outbreak strain with onset 1/1/2014–7/22/2014. We conducted open-ended interviews to identify common exposures in the week prior to onset, administered supplemental questionnaires to refine hypotheses, collected products for testing, and performed traceback investigations.

Results: We identified 31 case-patients in 16 states; 22% (5/23) were hospitalized. Ninety percent (19/21) of case-patients reported consuming chia seeds or powder; 79% (15/19) of those specifically reported consuming chia seed powder of variable brand names. Traceback identified a Canadian firm as the common supplier for the sprouted chia seed powder. Multiple products containing sprouted chia seed powder from this firm were recalled and FDA denied admission of these products into the US until testing could confirm the products were no longer contaminated. During the investigation, testing of chia-containing products yielded two more Salmonella strains (Hartford and Oranienburg) that also caused illnesses; these were included in the outbreak.

Conclusions: Epidemiologic, traceback, and laboratory evidence identified sprouted chia seed powder processed at a single firm as the outbreak source. Although sprouted chia seeds are a novel Salmonella outbreak vehicle, this investigation highlights the well-documented risks for foodborne illness associated with the sprouting process. Firms choosing to produce sprouted seed products should follow available guidance to reduce the risk of bacterial contamination.

Listeria monocytogenes linked to whole apples used in commercially produced, prepackaged caramel apples – United States, 2014-2015

To be presented at the U.S. Centers for Disease Control and Prevention’s 64th Annual Epidemic Intelligence Service (EIS) conference April 20-23 in Atlanta.

caramel.appleBackground: Listeria monocytogenes (Lm) infection is the third leading cause of death from foodborne illness in the United States. Lm isolates undergo pulsed-field gel electrophoresis (PFGE) and whole genome sequencing (WGS) to identify disease clusters. In November 2014, two multistate clusters of Lm infections with distinct PFGE patterns were detected. Due to geographic and temporal overlap and a case with co-infection, they were investigated together to identify the source and prevent illnesses.

Methods: Cases were defined as illnesses with highly related Lm strains by WGS reported to PulseNet, the national molecular subtyping network for foodborne disease surveillance, with onset from 10/17/2014 to 2/12/2015. Information was collected on foods consumed in the weeks before illness onset using hypothesis-generating questionnaires and open-ended interviews. Case-patient food exposures were compared with data from listeriosis patients with genetically unrelated Lm using Fisher’s exact test. Traceback was performed to identify the suspect food source. WGS was performed on all case-patient, produce, and environmental isolates.

Results: Thirty-five cases from 12 states and 1 from Canada were identified; 34 patients were hospitalized and seven died. Three cases of meningitis occurred among healthy children. Twenty-eight (90%) of 31 patients reported consuming prepackaged caramel apples (multiple brands) compared with 1 (2.8%) of 36 patients with unrelated Lm isolates (p<0.001). Environmental and produce samples from a common apple supplier were highly related to clinical isolates by WGS. Three caramel apple producers and the apple supplier issued voluntary recalls.

Conclusions: Whole apples used in prepackaged caramel apples were the outbreak source. This is a new vehicle for Lm infections. Research is needed to understand factors specific to caramel apple production to prevent further contamination and illness.

Outbreak of Salmonella Newport infections linked to cucumbers – United States, 2014

To be presented at the U.S. Centers for Disease Control and Prevention’s 64th Annual Epidemic Intelligence Service (EIS) conference April 20-23 in Atlanta. (1)Background: Salmonella causes approximately 1 million foodborne infections and 400 deaths annually in the United States. In August 2014, PulseNet, the national molecular subtyping network for foodborne disease surveillance, detected a multistate cluster of Salmonella Newport (SN) infections with an indistinguishable pulse-field gel electrophoresis pattern. This strain has previously been linked to tomatoes from the Delmarva Peninsula of the Eastern US. We investigated to identify the source and prevent further illnesses. Methods: A case was defined as an illness with the outbreak strain with onset from 5/20/2014- 9/30/2014. Information was collected on travel, restaurant, and food exposures in the 7 days before illness onset using a structured questionnaire. Reported food frequencies were compared to the 2006-2007 FoodNet Population Survey. A non-regulatory traceback was performed to identify the source of food items consumed in illness sub-clusters. Whole genome sequencing (WGS) was conducted to further characterize relatedness of Salmonella isolates.

Results: A total of 275 cases from 29 states and DC were identified; 34% (48/141) were hospitalized and 1 death was reported. A significantly higher percentage of ill persons consumed cucumbers in the week before illness onset than expected, (62% vs. 46.9%, p=0.002). Traceback of 8 illness subclusters led to a common cucumber grower in the Delmarva region of Maryland. WGS analysis showed that genetic sequences of clinical isolates from MD and DE were highly related but distinct from a NY sub-cluster.

Conclusions: Epidemiologic and traceback evidence suggest cucumbers were a major source of illness in this outbreak. This is the first multistate outbreak of SN infections linked to a produce item from the Delmarva Peninsula other than tomatoes, suggesting an environmental reservoir may be responsible for recurring outbreaks.

Campylobacter jejuni infection associated with raw milk consumption – Utah, 2014

To be presented at the U.S. Centers for Disease Control and Prevention’s 64th Annual Epidemic Intelligence Service (EIS) conference April 20-23 in Atlanta.

colbert.raw.milkSummary: Despite routine testing, raw milk from a Utah dairy sickened 99 people with Campylobacter; 1 died and 10 were hospitalized. A 2-month shutdown failed to stop the outbreak and the dairy’s raw milk permit was revoked.


Background: In Utah, raw milk sales are legal from farm to consumer. Despite routine bacterial and coliform

counts by the Utah Department of Agriculture and Food (UDAF), raw milk-related illnesses occur. In May 2014, the Utah Department of Health (UDOH) identified a cluster of 3 Campylobacter jejuni infections with indistinguishable pulsed-field gel electrophoresis (PFGE) patterns. All patients reported consuming Dairy A’s raw milk. Routine testing of UDAF-licensed Dairy A’s raw milk was acceptable. We investigated to identify a source and prevent additional infections.

Methods: UDAF used onsite milk neutralization technique to preserve C. jejuni during testing. Utah’s electronic disease surveillance system identified cases. Confirmed illness was defined as diarrhea caused by C. jejuni matching the cluster PFGE pattern. Probable illness was diarrhea and contact with a confirmed patient or raw milk purchased from Dairy A. Confirmed patients were interviewed by using a standardized questionnaire.

Results: During May 9–July 31, a total of 89 (52 confirmed and 37 probable) cases were identified. Eleven (21.2%) confirmed patients were hospitalized; 1 died. Twenty-five (48.1%) confirmed patients reported having consumed Dairy A raw milk. Fifteen (28.8%) confirmed patients reported having eaten queso fresco. Dairy A’s raw milk yielded C. jejuni with the cluster PFGE pattern. UDAF suspended Dairy A’s raw milk permit on August 4 for 2 months. Additional cases occurred in November; UDAF revoked Dairy A’s raw milk permit on December 1.

Conclusions: Routine testing of raw milk does not ensure its safety. Mandatory reporting, timely sample collection, pathogen testing, and onsite milk neutralization likely led to C. jejuni detection. Linking case and raw milk PFGE patterns might identify the source and allow implementation of control measures.

100 sick onboard Celebrity cruise ship

Up to 100 passengers have are being reported as sick from a possible Norovirus outbreak onboard the Celebrity Infinity.

vomit cruiseAccording to the Centre for Disease Control (CDC) 95 out of 2,117 passengers along with 5 crew members have been reported sick from gastrointestinal illness. The CDC has not yet confirmed that it’s Norovirus but in most outbreaks onboard it usually is. Passengers and crew have been having vomiting and diarrhea.

The CDC has also stated that 8 stool specimens from passenger and crew have been collected for testing. A CDC Vessel Sanitation Program environmental health officer and one epidemiologist are to board the 91,000 gross ton ship once it arrives in San Diego, CA on April 13. The Celebrity Infinity began the voyage on March 29th from Fort Lauderdale, Florida on a 15 night Panama Canal cruise.

Cooling food in a restaurant so people don’t barf

Data collected by the Centers for Disease Control and Prevention (CDC) show that improper cooling practices contributed to more than 500 foodborne illness outbreaks associated with restaurants or delis in the United States between 1998 and 2008.

sitting.iceCDC’s Environmental Health Specialists Network (EHS-Net) personnel collected data in approximately 50 randomly selected restaurants in nine EHS-Net sites in 2009 to 2010 and measured the temperatures of cooling food at the beginning and the end of the observation period. Those beginning and ending points were used to estimate cooling rates. The most common cooling method was refrigeration, used in 48% of cooling steps. Other cooling methods included ice baths (19%), room-temperature cooling (17%), ice-wand cooling (7%), and adding ice or frozen food to the cooling food as an ingredient (2%).

Sixty-five percent of cooling observations had an estimated cooling rate that was compliant with the 2009 Food and Drug Administration Food Code guideline (cooling to 41°F [5°C] in 6 h). Large cuts of meat and stews had the slowest overall estimated cooling rate, approximately equal to that specified in the Food Code guideline. Pasta and noodles were the fastest cooling foods, with a cooling time of just over 2 h. Foods not being actively monitored by food workers were more than twice as likely to cool more slowly than recommended in the Food Code guideline. Food stored at a depth greater than 7.6 cm (3 in.) was twice as likely to cool more slowly than specified in the Food Code guideline. Unventilated cooling foods were almost twice as likely to cool more slowly than specified in the Food Code guideline.

Our data suggest that several best cooling practices can contribute to a proper cooling process. Inspectors unable to assess the full cooling process should consider assessing specific cooling practices as an alternative. Future research could validate our estimation method and study the effect of specific practices on the full cooling process. 

Quantitative data analysis to determine best food cooling practices in U.S. restaurants

Journal of Food Protection®, Number 4, April 2015, pp. 636-858, pp. 778-783(6)

Schaffner, Donald W.; Brown, Laura Green; Ripley, Danny; Reimann, Dave; Koktavy, Nicole; Blade, Henry; Nicholas, David


Everything comes down to poo

My mom said she got foodborne illness a couple of years ago, and it affected her for over a year.

ben.stool.sample.nov.09She didn’t contact the health unit and didn’t go the hospital, because that’s how we roll.

My mom’s like most people I chat with about poop: it’s sorta embarrassing. It’s nerds like Chapman (his kit, right) that get stool samples and find out they’re part of a state-wide outbreak.

The U.S. Centers for Disease Control reports that increased availability and rapid adoption of culture-independent diagnostic tests (CIDTs) is moving clinical detection of bacterial enteric infections away from culture-based methods. These new tests do not yield isolates that are currently needed for further tests to distinguish among strains or subtypes of Salmonella, Campylobacter, Shiga toxin–producing Escherichia coli, and other organisms.

Public health surveillance relies on this detailed characterization of isolates to monitor trends and rapidly detect outbreaks; consequently, the increased use of CIDTs makes prevention and control of these infections more difficult (1–3). During 2012–2013, the Foodborne Diseases Active Surveillance Network (FoodNet*) identified a total of 38,666 culture-confirmed cases and positive CIDT reports of Campylobacter, Salmonella, Shigella, Shiga toxin–producing E. coli, Vibrio, and Yersinia. Among the 5,614 positive CIDT reports, 2,595 (46%) were not confirmed by culture. In addition, a 2014 survey of clinical laboratories serving the FoodNet surveillance area indicated that use of CIDTs by the laboratories varied by pathogen; only CIDT methods were used most often for detection of Campylobacter (10%) and STEC (19%).

Maintaining surveillance of bacterial enteric infections in this period of transition will require enhanced surveillance methods and strategies for obtaining bacterial isolates.

Bacterial enteric infections detected by culture-independent diagnostic tests — FoodNet, United States, 2012–2014

CDC MMWR March 13, 2015 / 64(09);252-257

Martha Iwamoto, Jennifer Y. Huang,. Cronquist, Carlota Medus, Sharon Hurd, Shelley Zansky, John Dunn, Amy M. Woron, Nadine Oosmanally, Patricia M. Griffin, John Besser, Olga L. Henao

Hepatitis A vaccines work: Michigan, 2013

Hepatitis A virus (HAV) infections among persons with developmental disabilities living in institutions were common in the past, but with improvements in care and fewer persons institutionalized, the number of HAV infections has declined in these institutions. However, residents in institutions are still vulnerable if they have not been vaccinated.

hepatitis.AOn April 24, 2013, a resident of a group home (GH) for adults with disabilities in southeast Michigan (GH-A) was diagnosed with hepatitis A and died 2 days later of fulminant liver failure. Four weeks later, a second GH-A resident was diagnosed with hepatitis A. None of the GH-A residents or staff had been vaccinated against hepatitis A. Over the next 3 months, six more cases of hepatitis A were diagnosed in residents in four other Michigan GHs. Three local health departments were involved in case investigation and management, including administration of postexposure prophylaxis (PEP). Serum specimens from seven cases were found to have an identical strain of HAV genotype 1A.

This report describes the outbreak investigation, the challenges of timely delivery of PEP for hepatitis A, and the need for preexposure vaccination against hepatitis A for adults living or working in GHs for the disabled.

CDC MMWR 64(06);148-152

Susan R. Bohm, Keira Wickliffe Berger, Pamela B. Hackert, Richard Renas, Suzanne Brunette, Nicole Parker, Carolyn Padro, Anne Hocking, Mary Hedemark, Renai Edwards, Russell L. Bush, Yury Khudyakov, Noele P. Nelson, Eyasu H. Teshale

Outbreaks from raw milk on the rise in US

The U.S. Centers for Disease Control reports that outbreaks caused by raw milk increased over a six-year period, according to a newly released CDC study. The study reviewed outbreaks caused by raw milk–milk that has not been pasteurized to kill disease-causing germs–in the United States that were reported to CDC from 2007-2012. The study analyzed the number of outbreaks, the legal status of raw milk sales in each state, and the number of illnesses, hospitalizations, and deaths associated with these outbreaks.

colbert.raw.milkMore states are legalizing the sale of raw milk even though this leads to an increase in the number outbreaks.

Findings also showed that the number of states that have legalized the sale of raw milk has also increased. In 2004, there were 22 states where the sale of raw milk was legal in some form; however, this number increased to 30 in 2011. Eighty-one percent of outbreaks were reported in states where the sale of raw milk was legal.

Children were at the highest risk for illness from raw milk. About sixty percent of outbreaks involved at least one child younger than five years of age.

 Raw milk is a risk for human health.

You cannot look at, smell, or taste raw milk to determine if it is safe. Cows and other animals can appear healthy and clean, but can still have germs, like Salmonella and E. coli, which can cause illnesses in humans.

Milk cannot be collected without introducing some bacteria– even under ideal conditions of cleanliness. Unless the milk is pasteurized, these bacteria can multiply.

Even raw milk supplied by “certified,” “organic,” or “local” dairies has no guarantee of being safe. Raw milk from grass-fed animals is not considered safe either. 



Vaccination works: Hepatitis A rates fall in US children, rise in adults

As all children attending two schools in Portsmouth, UK will be vaccinated against Hepatitis A in light of a potential outbreak, researchers at the U.S. Centers for Disease Control report that adults are particularly at risk for Hep A infections.

hepatitis.ABackground. In recent years, few US adults have had exposure and resultant immunity to hepatitis A virus (HAV). Further, persons with liver disease have an increased risk of adverse consequences if they are infected with HAV.

Methods. This study used 1999–2011 National Notifiable Diseases Surveillance System and Multiple Cause of Death data to assess trends in the incidence of HAV infection, HAV-related hospitalization, and HAV-related mortality.

Results. During 1999–2011, the incidence of HAV infection declined from 6.0 cases/100 000 to 0.4 cases/100 000. Similar declines were seen by sex and age, but persons aged ≥80 years had the highest incidence of HAV infection in 2011 (0.22 cases/100 000). HAV-related hospitalizations increased from 7.3% in 1999 to 24.5% in 2011. The mean age of hospitalized cases increased from 36.0 years in 1999 to 45.1 years in 2011. While HAV-related mortality declined, the mean age at death among decedents with HAV infection increased from 48.0 years in 1999 to 76.2 years in 2011. The median age range of decedents who had HAV infection and a liver-related condition was 51.0 to 68.0 years.

Conclusions. Although vaccine-preventable, HAV-related hospitalizations increased greatly, mostly among adults, and liver-related conditions were frequently reported among HAV-infected individuals who died. Public health efforts should focus on the need to assess protection from hepatitis A among adults, including those with liver disease.

Trends in disease and complications of hepatitis A virus infection in the United States, 1999–2011: a new concern for adults

Journal of Infectious Diseases [ahead of print]

Kathleen N. Ly and R. Monina Klevens