Yersinia enterocolitica outbreak over in Sweden, iceberg lettuce is suspected

Outbreak News Today reports in a follow-up on the Yersinia enterocolitica outbreak in Sweden, The Swedish Public Health Agency says the outbreak of Yersinia enterocolitica is over.

During the period January and up to the beginning of February, twice as many people fell ill with Yersinia infection as during the same period in a normal year. Of a total of 53 cases of Yersinia enterocolitica, 33 were resident in the regions of Stockholm, Västra Götaland and Halland.

Isolates from 24 of these cases were typed by whole genome sequencing, and 16 outbreak cases with clustered isolates could be identified.

A contaminated batch of iceberg lettuce distributed to a restaurant chain is the suspected source of infection.

Listeria in the news again

 

Food company Ready to Eat has announced a Listeria outbreak in several of their pre-packaged meals.
Ready to Eat, which produces ‘Muscle Fuel’ pre-made meals, said the meals affected are the ‘Vegetarian Chickpea and Pumpkin Rosti on Spinach Salad’ and the ‘Turkish Style Chicken & Rice’ with best before dates of August 4th, August 5th, August 6th, 2017.
Other meals are unaffected, the company says.
Any customers in possession of one of the affected meals are being urged to discard it immediately.
In a statement, Ready to Eat CEO Hamish Coulter said they were horrified when they received the news.
“To learn that one of our trusted produce suppliers has let us down is extremely disappointing.”
The Hamilton-based company was informed on Friday afternoon that its supplier Vegeez had returned a positive result for Listeria in one of its recent batches of cabbage.
On Friday evening the company contacted the 139 customers affected.
Vegeez general manager Glen Reid said it had taken full responsibility for the “very rare” event.
Mr Reid said in total there were 15 companies supplied with the affected cabbage, but all other companies managed to dump the product before using it.
Mr Coulter apologised to the company’s customers and said they were putting in measures to ensure this did not happen again.
The company has discontinued the use of coleslaw for the foreseeable future.
If any customer has consumed what they believe to be a contaminated meal they are advised to seek medical advice.
All customers will be contacted again this week with refunds issued.

I stumbled across an interested paper published in the Journal of Food Protection in February 2017 investigating the fate of Listeria monocytogenes , pathogenic Yersinia enterocolitica , and Escherichia coli O157:H7 gfp+inoculated in low numbers into ready-to-eat baby spinach and mixed-ingredient salad (baby spinach with chicken meat).

A quick synopsis of the study showed that when mixed-ingredient salad was stored at 8°C during shelf life, only L. monocytogenes increased significantly, reaching 3.0 log CFU/g within 3 days. The 8°C reflects maximum refrigerator temperature storage in Sweden.

In plain baby spinach, only pathogenic Y. enterocolitica populations increased significantly during storage for 7 days, and this was exclusively at an abuse temperature (15°C). Thus, mixing ready-to-eat leafy vegetables with chicken meat strongly influenced levels of inoculated strains during storage. 

The authors then translated the numbers into risks of infection. The risk of listeriosis (measured as probability of infection) was 16 times higher when consuming a mixed-ingredient salad stored at 8°C at the end of shelf life, or 200,000 times higher when stored at 15°C, compared with when consuming it on the day of inoculation. They conclude that efforts should focus on preventing temperature abuse during storage to mitigate the risk of listeriosis.

Söderqvist K1, Lambertz ST1,2, Vågsholm I1, Fernström LL1, Alsanius B3, Mogren L3, Boqvist S1. Fate of Listeria monocytogenes , Pathogenic Yersinia enterocolitica , and Escherichia coli O157:H7 gfp+ in Ready-to-Eat Salad during Cold Storage: What Is the Risk to Consumers? J Food Prot. 2017 Feb;80(2):204-212. doi: 10.4315/0362-028X.JFP-16-308.

133 sickened in Norway: ‘Improvements required in production processing of fresh salad products’

In May 2014, a cluster of Yersinia enterocolitica (YE) O9 infections was reported from a military base in northern Norway. Concurrently, an increase in YE infections in civilians was observed in the Norwegian Surveillance System for Communicable Diseases. We investigated to ascertain the extent of the outbreak and identify the source in order to implement control measures.

radicchioA case was defined as a person with laboratory-confirmed YE O9 infection with the outbreak multilocus variable-number tandem repeat analysis (MLVA)-profile (5-6-9-8-9-9). We conducted a case–control study in the military setting and calculated odds ratios (OR) using logistic regression. Traceback investigations were conducted to identify common suppliers and products in commercial kitchens frequented by cases. By 28 May, we identified 133 cases, of which 117 were linked to four military bases and 16 were civilians from geographically dispersed counties. Among foods consumed by cases, multivariable analysis pointed to mixed salad as a potential source of illness (OR 10.26; 95% confidence interval (CI): 0.85–123.57). The four military bases and cafeterias visited by 14/16 civilian cases received iceberg lettuce or radicchio rosso from the same supplier. Secondary transmission cannot be eliminated as a source of infection in the military camps.

The most likely source of the outbreak was salad mix containing imported radicchio rosso, due to its long shelf life. This outbreak is a reminder that fresh produce should not be discounted as a vehicle in prolonged outbreaks and that improvements are still required in the production and processing of fresh salad products.

National outbreak of Yersinia enterocolitica infections in military and civilian populations associated with consumption of mixed salad, Norway, 2014

Eurosurveillance, Volume 21, Issue 34, 25 August 2016, DOI: http://dx.doi.org/10.2807/1560-7917.ES.2016.21.34.30321

E MacDonald, M Einöder-Moreno, K Borgen, L Thorstensen Brandal, L Diab, Ø Fossli, B Guzman Herrador, AA Hassan, GS Johannessen, EJ Johansen, R Jørgensen Kimo, T Lier, BL Paulsen, R Popescu, C Tokle Schytte, K Sæbø Pattersen, L Vold, Ø Ørmen, AL Wester, M Wiklund, K Nygård

http://www.eurosurveillance.org/ViewArticle.aspx?ArticleId=22561

Bubonic plague hung around in Europe

The plague bacterium Yersinia pestis may have lurked in a Medieval European reservoir for at least 300 years, researchers suggest January 13 in PLOS ONE.

thing.that.wouldn't.leave.belushiThe second of two major plague pandemics hit Europe from the 14th to 16th centuries, peaking during the Black Death from 1346 to 1353. The new study weighs in on a longstanding debate over what fed the pandemic, strains of the bacterium traveling on waves of trade from Asia via the Silk Road or a homegrown biological reservoir such as lice.

Researchers analyzed DNA from 30 skeletal remains spanning the 14th to 17th centuries. Eight carried strains of Y. pestis, and all bore genetic similarity to each other and to those found in previously sampled European plague victims. Strains from Asia would have injected more genetic variety. Instead, the results suggest that at least one strain of Y. pestis stuck around in Europe for a long time, researchers write.

The thing that wouldn’t leave from topo morto on Vimeo.

43 sickened: Yersinia in raw milk in Finland

In March 2014, a Yersinia pseudotuberculosis (YP) outbreak was detected by a municipal authority in southern Finland.

napoleon.raw.milkWe conducted epidemiological, microbiological and traceback investigations to identify the source. We defined a case as a person with YP infection notified to the National Infectious Disease Registry between February and April 2014, or their household member, with abdominal pain and fever ≥ 38 °C or erythema nodosum. Healthy household members were used as household-matched controls. We identified 43 cases and 50 controls. The illness was strongly associated with the consumption of raw milk from a single producer. The odds ratio of illness increased with the amount of raw milk consumed. Also previously healthy adults became infected by consuming raw milk. Identical YP strains were identified from cases’ stool samples, raw milk sampled from a case’s refrigerator and from the milk filter at the producer’s farm. The producer fulfilled the legal requirements for raw milk production and voluntarily recalled the raw milk and stopped its production.

We advised consumers to heat the raw milk to 72 °C for 15 s. Current legislation for raw milk producers should be reviewed and public awareness of health risks linked to raw milk consumption should be increased.

 Outbreak of Yersinia Pseudotuberculosis O:1 Infection Associated With Raw Milk Consumption, Finland, Spring 2014

Eurosurveillance, Volume 20, Issue 40, 08 October 2015

T Pärn, S Hallanvuo, S Salmenlinna, A Pihlajasaari, S Heikkinen, H Telkki-Nykänen, M Hakkinen,  J Ollgren, S Huusko, R Rimhanen-Finne

http://www.eurosurveillance.org/ViewArticle.aspx?ArticleId=21268

Biggest PR screw-up in NZ for 2014? Bad lettuce

The handling of a food poisoning scare involving carrots and lettuce has been deemed the biggest public relations challenge this year by a Wellington PR firm.

lettuce.skull.e.coli.O145The handling of the Yersinia pseudotuberculosis issue by the Ministry for Primary Industries beat the closure of regional flight routes by Air New Zealand and Roger Sutton’s resignation by the State Services Commission to make the top of the list.

“In a year of dirty politics, what really concerned New Zealanders most was dirty lettuce and carrots,” BlacklandPR director Mark Blackham said.

“Everyone had these vegetables in our fridges, yet no one in authority could say for some time whether they were a health threat.

Millions of people were affected and little information is a recipe for fear, rumours and anger.”

Foodborne outbreaks: Learning opportunities, regardless of uncertainty, and should not be hidden

My latest column for Texas A&M’s Center for Food Safety:

powell.food.safety.going.publicThere was this one time, about 32 years ago, I was sitting in the kitchen with the mother of my university girlfriend.

She was peeling potatoes for boiling and mashing, and I smugly asked, why are you wasting so much potato?

“Because I don’t have all bloody day and if you’re so concerned, get off your bloody ass and bloody-well help.”

I’ve cooked ever since.

But what the mom and I didn’t know was that those potato skins could be contaminated with nasties like E. coli O157.

Potatoes, carrots, leeks, they’re grown in soil, and poop has various ways of getting into soil, so peeling potatoes should be like handling raw meat – you never bloody-well know what is contaminated and what isn’t.

Be the bug, follow the bug.

The folks at the U.K. Food Standards Agency, whose idea of science-based verification is to cook meat until it is piping hot, have apparently decided that E. coli O157:H7 – the dangerous kind – found on or in leeks, is the consumers’ responsibility.

Almost two months after revealing 250 people were sickened and one died with E. coli O157:H7 phage-type 8 over the previous eight months in 2011, linked to people handling loose raw leeks and potatoes in their homes, FSA decided to launch a campaign reminding people to wash raw vegetables to help minimize the risk of food poisoning.

leek_washNo information on how those 250 became sick and no information on farming and packing practices that may have led to such a massive contamination that so many people got sick, no information on anything: just advice to wash things thoroughly so that contamination can be spread throughout the kitchen.

This outbreak combines two of the central themes of conflict and public trust in all things food: when to go public, and blaming consumers.

Often during an outbreak of foodborne illness there are health officials who have data indicating that there is a risk, prior to the public (although social media is changing that equation).

During the lag period between the first public health signal and some release of public information, there are decision-makers who are weighing evidence with the impacts of going public. Multiple agencies and analysts have lamented that there is not a common playbook or decision tree for how public health agencies determine what information to release and when. Regularly health authorities suggest that how and when public information is released is evaluated on a case-by-case basis without sharing the steps and criteria used to make decisions.

On June 2, 2008, the U.S. Centers for Disease Control and Prevention (CDC) announced that it was investigating an ongoing multistate outbreak of human Salmonella serotype Saintpaul infections. CDC identified the consumption of raw tomatoes as the likely source of the illnesses in at least two states. By the time the outbreak was officially declared over on August 28, 2008, 1,442 people had been reported infected, at least 286 people had been hospitalized, and the infection may have contributed to two deaths. Despite the early identification of tomatoes as a potential pathogen source, jalapeño peppers were subsequently identified as the major source, with some implication of serrano peppers as well.

Was the public advisory to avoid raw tomatoes issued too early in the outbreak investigation, despite its intent as a control measure?  Some, including the Florida Tomato Committee may believe so, considering the outcome of the investigation and the substantial impact on the agriculture sector. The estimated economic cost to the tomato industry was more than $100 million in Florida and close to $14 million in Georgia.

In a 1999 news article about a Listeria monocytogenes outbreak, CDC foodborne illness epidemiologist Paul Mead summed up the conundrum that health officials face when reviewing preliminary data during an outbreak investigation: “Food safety recalls are always either too early or too late. If you’re right, it’s always too late. If you’re wrong, it’s always too early.”  Go public too early, and make a mistake, and a corporation or industry’s reputation could unduly suffer. Go public too late, and individuals and businesses may be denied critical information they could use to protect public health.

This balancing act was most recently on display in New Zealand, following 170 confirmed cases of Yersinia pseudotuberculosis and a further 59 suspected but not confirmed cases of infection, apparently linked to lettuce.

By early Oct. 2014, enough people were sick that Food Safety Minister Jo Goodhew was compelled to finger Pams Fresh Mesclun Salad Lettuce and Pams Fresh Express Lettuce, while stressing the list was not initially released because it showed no definitive cause for the illness.

This is a disturbing trend, in that people are demanding microbiological proof when none exists – epidemiology remains a powerful and preventative public health tool.

Canterbury medical officer of health Dr Alistair Humphrey said a draft report from Environmental Science and Research (ESR) made available the previous week identified lettuce and carrots from a particular supermarket chain as the source.

“Everybody involved in this work, including MPI, ESR, all the public health units and the Ministry of Health, have seen the results of the ESR study, which is quite clear. It is unequivocal and it does name the types of food that have led to this problem and it also names one particular product,” Humphrey told Radio New Zealand.

He claimed MPI asked public health officials to keep the name of the supermarket and the products involved a secret, but he decided to name the vegetables to protect the public.

“[MPI] felt they should work with the industry rather than naming the foods but, of course, that leaves the New Zealand public slightly at risk, in my view.”

Bureaucrats are terrified of discussions of risk.

Within days of the public announcement, dozens of N.Z. Herald readers affected by the illness sent in messages describing what they went through, with many saying they were left bedridden, drowsy and debilitated.

But then the backpedaling started, portraying Living Farms, the producers of Pam’s greens, as victims of a zealous media, and by Nov., epidemiology was dumped in favor of “no Yersinia pseudotuberculosis was detected in any samples.”

Yet internal e-mails under the Official Information Act show the Ministry for Primary Industries (MPI) was mindful of balancing the risk of further illness against the risk of panicking the public and a loss of trust in the food supply chain.

An email from MPI, dated 1 October, said it considered “there will be greater ongoing positive effect and influence, with lesser risk of negative results, by managing the food safety hazard at the most likely source, ie: with industry.”

public.healthMPI had been visiting farms and retailers to try and pinpoint the source of the bug.

The documents also showed MPI believed the best it could do was inform the public to wash all fruit and vegetables as a precaution.

But, in an email dated 1 October, MPI said it was likely that the suspected vegetables were contaminated with the bacteria internally, rather than just on the surface: “Meaning that washing of the produce by consumers will not afford protection from illness.” This information was not passed on to consumers.

I don’t envy anyone facing bloody accusations. Growers and others would be better served if there were clear, publicly available guidelines for when to go public about foodborne illness. And don’t bloody-well blame consumers unless it is warranted.

Dr. Douglas Powell is a former professor of food safety who shops, cooks and ferments from his home in Brisbane, Australia.

 DISCLAIMER: The views and opinions expressed in this blog are those of the original creator and do not necessarily represent that of the Texas A&M Center for Food Safety or Texas A&M University. 

127 sick with Yersinia in NZ: When should public health types go public with food safety risks?

Early findings into a severe gastroenteritis outbreak were withheld to avoid causing a public scare with limited information, the New Zealand Ministry for Primary Industries (MPI) says.

carrotjuiceI’ve heard the same shit for 20 years – we can’t tell the public, we know better and are paid better than the plebes, so we must know better.

We’ve worked with several farming groups over the decades with no problems.

People can handle discussions of risk.

Bureaucrats are terrified of discussions of risk.

About 127 people have been affected and 38 hospitalized by a Yersinia pseudotuberculosis outbreak since it appeared last month.

MPI deputy director general Scott Gallacher yesterday said lettuce and carrots had been associated with the outbreak in an Environmental Science and Research (ESR) draft report last week but the information was “not a slam dunk.”

Epidemiology is rarely a slam dunk.

Foodstuffs, the company that owns New World and Pak’n Save, said it had viewed the report which named two of its two products, Pam’s fresh express mesclun salad lettuce and Pam’s fresh express lettuce, as possible sources.

The company is investigating this and did not believe any of the potentially affected products were still on its shelves.

Gallacher fended off claims the MPI risked public health because it was more concerned about protecting supermarkets’ reputations.

Canterbury medical officer of health Dr Alistair Humphrey yesterday said the ESR draft report clearly identified bagged lettuce and carrots from a particular supermarket chain as the source.

Time for an epidemiology refresher in New Zealand, Or a political one; sick people vote with their barf.

27 sick with Yersinia and Campylobacter from raw milk in Finland

The first results from milk samples at a farm in Askola, Finland taken April 7 revealed Yersinia pseudotuberculosis and Campylobacter jejuni.

The number of people who drank milk from Uljaan tilamaito and experienced symptoms has still increased in Porvoo and in the neighboring municipalities (Askola, Lovisa, Borgnäs colbert.raw.milkand Sipoo). There are now 19 confirmed cases of Yersinia. Campylobakterier have so far been isolated from a total of eight people. Investigations are still ongoing for about twenty people.

Uljaan tilamaito pulled away all unpasteurized milk from the shops in early April.