Control of E. coli O157 on beef with bacteriophages

Efficacy of four bacteriophages (phages) and a cocktail for biocontrol of Escherichia coli O157 was assessed on beef samples stored at 4, 22 and 37 °C.

lunar.moduleSamples (3 × 3 × 1 cm) were contaminated withE. coli O157 (104 CFU/cm2) and treated with single phages: T5-like (T5), T1-like (T1), T4-like (T4) and O1-like (O1), or a cocktail at two titers: multiplicity of infection (MOI) = 1000 and MOI = 10. In contrast to previous studies, use of virucidal solution prevented over-estimation of phage efficacy. Irrespective of temperature and MOIs, T5 was most (P < 0.001) and O1 least (P < 0.05) effective for biocontrol of E. coliO157, with relative efficacy of other phages temperature dependent. At 4 °C, T1 (P < 0.05) and cocktail (P < 0.001) were more effective than T4. In contrast, T4 was equally (P = 0.08, at 37 °C) or less effective (P = 0.003, at 22 °C) than T5. Phages were more effective (P < 0.001) against E. coli O157 at warmer temperatures and high MOI.

As the beef supply chain includes hours of storage or transport at temperatures near 4 °C, this study demonstrates phages could significantly reduce E. coli O157 during this period.

Control of Escherichia coli O157 on beef at 37, 22 and 4 °C by T5-, T1-, T4-and O1-like bacteriophages

Food Microbiology Volume 51, October 2015, Pages 69–73, doi:10.1016/j.fm.2015.05.001

Liu, Y.D. Niu, R. Meng, J. Wang, J. Li, R.P. Johnson, T.A. McAllister, K. Stanford

http://www.sciencedirect.com/science/article/pii/S0740002015000878

E. coli in pigs: Real-time PCR

Escherichia coli is found naturally in the intestinal flora of pigs and, under certain circumstances, it causes a clinical picture of colibacillosis, a disease that can manifest itself as different conditions involving neonatal diarrhoea, post-weaning diarrhoea, oedema disease, septicaemia, etc…

pig-in-shock1Proper diagnosis includes a thorough anamnesis, a correct selection of samples and a complete differential diagnosis supported by various techniques. The mere detection of pathogenic strains does not justify the disease in every case due to the often finding of asymptomatic carriers. Identifying relevant virulence strains and differentiating them from other normal gut flora is a highly topical diagnostic challenge. And the real time PCR (qPCR) applied to the detection of virulence factors (VFs) of E. coli has rised up as a powerful tool able to generate useful information.

Based on the extraction of nucleic acids from different biological matrices (culture, faeces, intestinal or rectal swab), qPCR assays recognize specific genomic regions of E. coli encoding different VFs. In this work, each trial was designed to detect a different VF. An additional qPCR (ECCO) was used to confirm the presence of E. coli in the samples and to ensure that all stages of the technique had been performed correctly. qPCR is a qualitative assay, but it’s also quantitative (Figure 1), which is a significant advantage over its predecessor, conventional PCR.

The smaller the Cq value, the higher the initial concentration of the parameter studied in the sample.

Evaluation of virulent strains in colibacillosis was traditionally achieved by an initial microbiological culture, then isolation of colonies of E. coli and subsequent characterization of their VFs. The main disadvantage of this method is that the analysis can only be performed on a limited number of selected isolates, the accuracy of the diagnosis relying on the assumption that these are representative in the total population of E. coli in the sample studied. This way, there is a risk of omitting non-majority populations of E. coli that are, however, clinically relevant.

qPCR provides the possibility of analysing the VFs directly on the clinical sample. This methodology avoids intermediate culture steps and their respective determinations on each of the different selected isolates, leading to considerable savings in time and costs. Given the quantitative nature of the technique, a relationship can be established between the number of copies detected for a specific virulence gene and the total population of E. coli in the sample. This way we could interpret the possibility of isolating a strain with a particular combination of VFs.

This methodology has certain limitations due to the indeterminate number of copies of the individual genes encoding each VF within different bacterial populations. However, it meets the proposed objective: to assess the possibility of finding E. coli with a particular combination of VFs in the sample.

In conclusion, qPCR applied directly to clinical samples provides substantial savings of time and resources, as well as information leading to an interpretation providing solutions for the sensitive diagnosis of porcine colibacillosis.

Boston eateries cited for serious violations

City inspectors last year found multiple instances of the most serious type of health and sanitary code violations at nearly half of Boston’s restaurants and food service locations, according to a Globe review of municipal data.

At least two violations that can cause foodborne illness — the most serious of three levels — were discovered at more than 1,350 restaurants across Boston during 2014, according to records of inspections at every establishment in the city that serves food, including upscale dining locations, company cafeterias, takeout and fast-food restaurants, and food trucks.

Five or more of the most serious violations were discovered at more than 500 locations, or about 18 percent of all restaurants in the city, and 10 or more of the most serious violations were identified at about 200 eateries.

A violation is classified under the most serious category when inspectors observe improper practices or procedures that research has identified as the most prevalent contributing factors of foodborne illness.

Examples of such infractions include: not storing food or washing dishes at proper temperatures, employees not following hand-washing and glove-wearing protocols, and evidence that insects or rodents have been near food.

Last year, the location with the highest total of the most serious types of violation was Best Barbecue Kitchen, a small butcher shop and takeout restaurant on Beach Street in Chinatown, which racked up 70 such violations, according to city records.

That restaurant also had the highest total of violations in all categories — at 219 — last year. As of last month, Best Barbecue Kitchen had accumulated the highest number of the most serious violations: 130, dating back to 2007, when the city began posting the data online. It also had the second-highest total of violations of any type: 614.

The restaurant that had the second-highest total of the most serious violations last year was Cosi, a cafe and sandwich chain inside South Station, where 50 were found. The restaurant with the third-highest total of the most serious violations last year could be found several feet away inside South Station: Master Wok, which had 45.

Staff members at all three restaurants declined to comment last week and requests to speak with managers went unanswered.

Bob Luz, president and chief executive of the Massachusetts Restaurant Association, said the safety of customers is the top priority for restaurant owners.

“Food safety is number one for every restaurateur in the state, and obviously it’s something we consider as incredibly important,” said Luz.

Uh-huh.

Canada, how long does it take to write a PR? 13 sick with E. coli infections and possible link to leafy greens

The leafy greens cone of silence continues to silence or impair epidemiology across North America.

leafy.green.lettuceThe Public Health Agency of Canada says today that 13 people across Canada were sickened with E. coli O157:H7 with a possible link to leafy greens, and that the investigation concluded on May 12, 2015.

Two weeks is a long time to get approval for a simple press release.

“Although leafy greens were identified as a possible source of illness, a specific source of the outbreak could not be confirmed.

“During the investigation, exposure to leafy greens was identified as a possible source of illness. Leafy greens can include all varieties of lettuces and other green leaf vegetables such as kale, spinach, arugula, or chard. The Canadian Food Inspection Agency conducted an investigation into leafy greens, however no specific food products were identified as the source of the outbreak.”

And the usual boilerplate:

waynes-world-monkeys-might-fly-out--e1297873880696“Canadians are reminded to always follow safe food handling practices to avoid illness. Wash your hands thoroughly before preparing or eating food. Wash raw fruits and vegetables thoroughly with clean, safe running water before you prepare and eat them.”

Yup, 13 people from Alberta to Newfoundland got sick with the same E. coli because of bad handwashing (not).

Inspections and audits are never enough: Blame the consumer, German version, deadly Salmonella outbreak traced to Bavarian egg farm

Despite visiting the infected farm on a number of occasions, finding Salmonella and seeing an unusual amount of dead chickens, Bavarian health authorities took no action, leading to widespread illness and multiple deaths across Europe last summer, Sputnik reported.

salmonella.eggsAn outbreak of Salmonella which led to hundreds of people falling ill across Europe last summer, and was linked to several deaths, has been traced back to contaminated eggs from a farm in Bavaria, German media has revealed.

The farm is owned by the Bayern Ei company, one of Germany’s largest egg producers which operates four chicken factories, where hens lay some one million eggs a day.

At the farm in question, in the southern region of Lower Bavaria, where hundreds of chickens were being found dead each day, company bosses initially told employees the death rate was due to chickens dying from heat.

According to the investigation carried out by reporters from Germany’s Suddeutsche Zeitung and Bayerischen Rundfunk, the Bavarian Health and Food Safety Authorities knew about the presence of Salmonella at the farm, having found evidence of the infection in two separate investigations.

However, the authorities turned a blind eye and took no action to take products from the farm off the market, since “the responsible customer” is aware that “eggshells are not sterile,” and should wash their hands after handling an egg.

Hamburgers and Memorial Day

As I devoured a 160F tip-sensitive thermometer verified hamburger this morning while watching Tampa beat New York in hockey playoffs, I was reminded that NY Times foodie Sam Sifton took 1,600 words last year to describe how to cook the ‘perfect burger’ and no mention of thermometers.

The Times wonders why it’s losing readers (and please, stop sending me the daily offers to resubscribe for almost nothing, it’s embarrassing).

Food porn always trumps food safety, until someone gets sick.

Bask in Memorial Day, my fellow U.S. citizens, remember those who gave and continue to give, and try not to make anyone barf.

hamburger-safe and unsafe-thumb-450x138-175

193 take part in mass lawsuit over UK Toby Carvery Norovirus outbreak

Almost 200 people are taking part in a group legal action against an Exeter restaurant following the outbreak of norovirus.

sorry-technical-difficulties-600x337-300x169Lawyers who specialize in helping victims of illness outbreaks in the UK and abroad are investigating the norovirus outbreak at Toby Carvery at the Exeter Arms, Middlemoor.

Initially it was thought that in excess of 100 people could have been affected by the outbreak in March.

But solicitors Irwin Mitchell have now revealed that it is representing 193 people in relation to the case.

The restaurant chain confirmed that tests run by the Environmental Health department, after a man was sick in the restaurant foyer in the evening of Sunday, March 29, tested positive for the virus.

the-exeter-arms-in-middlemoorThe pub underwent a deep clean overnight on Thursday, April 2, but continued to trade over the busy Easter bank holiday weekend when more customers fell ill, finally closing on Tuesday, April 7.

Scores of people claim to have visited Toby Carvery between Monday, March 30, and Easter Sunday, April 5, and since become ill with sickness and diarrhea for several days. Restaurant staff were also affected.

New regs to control Vibrio in raw oysters

I don’t eat raw oysters.

Lifelong Brisbane residents I know will not eat oysters, raw or cooked (and we have an abundant supply — of oysters, and lifelong Brisbane residents).

raw.oysters.washJoNel Aleccia of The Seattle Times writes that when a work trip sent Jill Poretta to Seattle two summers ago, the New Jersey resident decided to make a vacation of it, a chance to see the sights and enjoy the city’s fine dining.

But an appetizer plate of mixed oysters soon spoiled the trip. The day after her dinner at a restaurant on the central waterfront, Poretta became so violently ill she had to take a cab to a hospital at 3 a.m.

“I couldn’t get out of the car,” recalled the 43-year-old legal researcher from Haddonfield, N.J. “I’m vomiting as soon as I walk in the door.”

Poretta had to cut short her trip and head home, where she says she felt exhausted and ill for two weeks. Tests showed she’d contracted Vibrio parahaemolyticus, known as Vp, a leading cause of seafood poisoning in the U.S.

In July 2013, her case was one of four traced to Hammersley Inlet, an arm of water in southwest Puget Sound. State health officials closed the shellfish-growing area — but only after Poretta and others had gotten sick.

Starting this month, there’s a new approach — a first-in-the-nation effort by state health officials and shellfish growers — to curb heat-loving Vp long before it hits the plate. It requires quicker cooling of oysters when air and water temperatures get too warm and closing at-risk commercial beds before illnesses occur.

The protocol requires real-time monitoring to determine how fast harvested oysters must be cooled to a safe 50 degrees — and when they shouldn’t be gathered at all.

The rules aims to reduce the 40 to 45 infections tied to Washington oysters that are confirmed each year and another 6,000 to 7,000 cases that go undiagnosed, health officials said.

 “Anytime you’re basically waiting for illnesses to trigger an action, it means you’ve missed your peak window for public-health protection,” said Laura Wigand Johnson, a marine and environmental scientist who led the state’s two-year process to put the Vp procedures in place.

But the new strategy, which took effect May 1 and runs through Sept. 30, has sent ripples of concern through Washington state’s commercial shellfish industry. That includes 329 licensed private growers and 39 tribal producers, though only about 150 deal in oysters, Johnson said.

All say they are in favor of reducing hard-to-predict Vp illnesses, even as they acknowledge the move requires new duties, new documentation and extra staff.

“It’s quite a shift in the way we do business as it relates to oysters for raw consumption,” said Bill Dewey, a spokesman for Shelton-based Taylor Shellfish Farms, the largest producer of farmed shellfish in the U.S. “We’re working through the nuts and bolts of how we do it.”

Those nuts and bolts apply to shellfish harvesters and dealers who supply fresh oysters to market to be eaten raw, not oysters designated for shucking or post-harvest processing.

There’s lots more at http://www.seattletimes.com/seattle-news/health/tighter-rules-aim-to-limit-seafood-poisoning-from-raw-oysters/

Restaurant inspection and disclosure LA style

A few weeks ago, NBC Los Angeles released an interactive map with confirmed food poisoning cases in L.A. county over the last 18 months. The map was published as a public service, so consumers know which restaurants to possibly avoid. But does this information really help consumers avoid food poisoning?

larry.david.rest.inspecI don’t think it’s very useful as a tool of where you’re going to have foodborne illness,” said Angelo Bellamo, the Director of Environmental Health for L.A. County.

“We’re only able to associate 25 cases each year [in L.A.] where we’ve had an outbreak that is more than a couple of people, and we’re able to verify the restaurant,” Bellamo said. “This is a big problem. It’s really under-reported, and our methods for actually determining whether or not restaurants are causing foodborne illnesses aren’t perfected yet. They’re nowhere near being perfected.”

The issue of concern is the collection of data. Right now, tips of potential contamination are collected through complaints people send to the office. Unfortunately, the information is few and far between. (Seriously, when was the last time you even considered calling the department after a particularly queasy meal?) So, rather than waiting for tips to hit their desks, officials are looking for ways to obtain it themselves.

“The use of social media is vital,” Bellamo said. He mentions a recent investigation where an investigator logged onto Yelp and found a number of complaints directed at a facility. The investigator contacted the reviewers and built the case from there. This is one way of using social media to further investigations, but also a strategy that’s far from perfected. “A lot of information in social media is not very useful, some is not credible, but there are nuggets in there,” Bellamo said. “If we found a way to selectively screen certain words or certain locations, there could be some real value there.” (Other cities have already begun using Twitter to identify outbreaks, which Bellamo believes will soon be part of L.A.’s efforts as well.)

One thing consumers shouldn’t do is simply trust the grade letter on the front window.

“It represents a snapshot in time,” Bellamo said. “That letter grade reflects the last inspection, which took place over the course of a couple of hours. You can’t look at just the letter grade.” Bellamo wants to change the current system, so that instead of simply showing how the last inspection went, to make it include an average of the last six inspections. “Good and bad days can happen to the best and poorest of restaurants,” he said. “An average score would be a lot more indicative of how that restaurant actually operates.”