FDA issues an update statement on Yuma E coli outbreak

Earlier this year, a serious multi-state outbreak of Escherichia coli O157:H7 infection was associated with consumption of Romaine lettuce from Yuma, Arizona.

The US FDA has now issued an update statement, though the investigation is not completed.  Tests of canal water close to the lettuce growing farms has tested positive for the outbreak strain of E. coli O157:H7, which is capable of producing Shigatoxin.  Infection with this microorganism can result in serious disease - 210 people in 36 states have become ill, with 96 hospitalizations and five deaths.

No single farm has been determined as the source of the outbreak, nor has the distribution chain been implicated so far.

The lettuce growing farms and canal are close to a Concentrated Animal Feeding Operation (CAFO), which can hold in excess of 100,000 head of cattle at any one time.   Since cattle can harbour the STEC E. coli involved in the outbreak, there is the possibility that the presence of the bacteria in the canal water originated from the CAFO.  Further testing of the CAFO and the animals would be necessary to establish a link.

The means by which the lettuces became contaminated must also be investigated.  Was the canal water used directly for irrigation, or were the bacteria somehow transferred from the canal water to the leaves?

Want to know more about the origin of Shigatoxin-producing E. coli?

 Bill Marler is a very rare individual: he is a lawyer with an ability to grasp the principles of microbiological food safety and to write about them in a way that is accessible to the general public.  Bill has been closely involved in food borne illness litigation since 1993, when he obtained a $15.6 million settlement for Brianne Kiner, a nine year old girl who suffered HUS and ultimately kidney, liver and pancreas failure after eating Jack-in-the-Box hamburger.  He has become a fiercely active food safety campaigner.

Recently, Bill conducted a literature review on the origins of Shigatoxin-producing Escherichia coli  and has published the first two parts on his food safety blog.  These publications are well worth reading - they are not written in highly technical language, but the reference list allows those readers sufficiently interested and capable to follow up his sources and read the original material.

Links to the first two parts are shown below:

http://www.marlerblog.com/lawyer-oped/where-the-hell-did-shiga-toxin-e-coli-come-from-a-literature-review---part-1/

http://www.marlerblog.com/case-news/where-the-hell-did-shiga-toxin-e-coli-come-from-a-literature-review---part-2/

There is just one problem with this review; Bill has taken away my option to set such a study of literature as an assignment for my postgraduate students in my course "Frontiers of Food Microbiology".  The students will still be expected to read and discuss the material, but I can't use their reviews for assessment purposes.  Thanks Bill!

Big One becomes Big Seven

Escherichia coli O157:H7 has now been joined on the FSIS most unwanted list by the "Big Six" - other strains of E. coli capable of producing Shigatoxin.

As we saw in May and June 2011 in the German outbreak, Shigatoxin-producing E. coli can cause a potentially deadly food borne infection that can leave survivors damaged for life.  The outbreak also resulted in huge economic loss in several European countries as fresh produce was either banned by authorities or shunned by consumers.

As of the 13th September 2011, these seven strains - O157:H7, O26, O11, O103, O121, O45 and O145 - will not be permitted in non-intact raw beef in USA.  If they are found to be present, the meat must either be destroyed or cooked before sale.

It has been a long road to get to this point. In October 2009, Bill Marler, a US attorney, filed a petition with USDA/FSIS for an Interpretive Rule declaring all enterohaemorrhagic Shigatoxin-producing serotypes of E. coli, including non-O157 serotypes, to be Adulterants within the meaning of the Federal Meat Inspection Act.

Not much has been heard since, though there has been a certain amount of correspondence.  Even the regulatory authorities didn't seem to have a united view.  On the 3rd June 2011, the Deputy Director of CFSAN, Donald Kraemer, stated on the FDA website "FDA considers any disease-causing strain of E. coli in food to be illegal”.  The FSIS deems only O157:H7 to be an adulterant.  Tellingly, Kraemer’s comment was removed from FDA website on 5th July 2011.

The new declaration is being hailed as a victory.  Elisabeth Hagen, head of food safety at the Department of Agriculture, said that this was "one of the biggest steps forward in the protection of the beef supply in some time.  We’re doing this to prevent illness and to save lives.”  A worthy cause.

However, I have some concerns about this optimism.  Will the reclassification of the Big Six make meat safer?  I'm not so sure.  Certainly, if these bacteria are detected in meat, the product will not be allowed on the market unless it is diverted to cooked products.  This may be a challenge for the meat processors - since 1994, O157:H7 in raw ground beef has been declared an adulterant with zero tolerance by FSIS.  In October 2007, the Topps Meat Company recalled 21.7 million pounds of ground beef, bringing the total recalls in the US between April and October 2007 to over 30 million pounds of red meat, mostly hamburger.  A company manufacturing frozen hamburger patties is unlikely to have the capacity to redirect this much meat to a cooking process and there may be difficulties in finding a buyer for the product, so it may have to be destroyed.

Secondly, as far as I am aware, there is no requirement for processors to test for these bacteria.  If this situation doesn't change, the first indication that something is wrong may still be when people start showing up at the hospital with gastrointestinal disease.

Thirdly, the cost of testing is currently very high and the testing may take up to 5 days, even when things go well.  I have already written about the impossibility of guaranteeing safe food by testing.

Finally, testing for the Big Seven will miss any Shigatoxin-producing non-members, as was the case with the German outbreak of O104:H4

The FSIS move is a good start and is motivated by good reasons.  However, the only way that safety of food can be improved is by development of risk management plans and rigorous application of critical control points throughout the food chain, including food service outlets, i.e. farm to fork.  Consumers should not receive contaminated food, but they too must play their part by prevention of cross contamination in the home and proper cooking of foods.  Future posts will deal with some of these approaches.

Where does that leave us with foods like sprouts?  Food for thought.

Since I wrote this article, Shawn Stevens has written an article "Big six declared Adulterants: Is it a good thing?" in Meatingplace.com, a blog for the meat industry in the US.  It seems that he too has some concerns. You may have to register to read the article, but registration is free.

Why do people buy insurance?

Do you sometimes think "Why do I keep paying insurance premiums for my car, boat, house, personal liability, camera etc?  I hardly ever make a claim".  In all the years I have been paying premiums, I have only once made a claim on my car insurance, and that was when one of the local semi-evolved simians stole it and drove it into a ditch.  Would you consider not insuring your house?  Would you be able to continue with business as usual if your offices burned down?  The chances of making a claim and getting some of the premiums back are quite small.

The probable reason we continue to pay is that it gives us peace of mind, knowing that if we do smash the car into a BMW or Rolls Royce, we won't be bankrupted by the repair bills for the other car.  We can drive, secure in the knowledge that we have that one covered.

Pasteurisation of milk is insurance and free.  A mild heat treatment kills all the pathogens that might have got into the milk during milking and transport, leaving the nutritional value essentially unchanged.  Why would you even consider drinking raw milk or eating raw cheese, knowing that there is a small chance that it could result in illness that would change your life or that of your family for ever?    There has been plenty written about the dangers of Escherichia coli O157:H7 and other STECs, so I'm not going to go over it again here.  (See other posts on E. coli by clicking the E. coli label at the RHS of this blog).

Please, this Christmas season, if you really want to eat and drink raw milk products, you can make an informed choice.  But don't give these products to children - they don't have that choice and a dose of E. coli O157:H7 can lead to HUS, which will probably ruin the rest of their lives.

Is food less safe these days? Part 1

Over the Christmas period I have done a lot of eating and drinking and being merry. I’ve also done a lot of thinking about food safety. In the last year we seem to have read almost daily of Listeria being found in deli meat, that babies have been poisoned by formula milk, children have been hospitalized with failing kidneys resulting from Escherichia coli O157:H7 infection, that melamine has turned up in yet another food product, or that an established company has closed its doors because of massive losses resulting from a food recall. Is our food less safe these days?

I don’t think that there is a simple answer, but I do have some suggestions. In this three-part posting I’ll share them with you.

I think that the whole thing can be analysed under a few subheadings.

Food Preparation: Some of my Christmas celebrations have involved large functions where caterers have served meals to hundreds of partygoers. These meals could not have been produced on the premises, so the food must have been pre-prepared and transported to the venue in insulated containers or perhaps reheated before serving. Other celebrations have been more modest, catered by the “bring a plate” approach. We have had barbecues, where foods were cooked outside on gas or charcoal burners. All of these scenarios have at least one thing in common – the foods were prepared by others for us, perhaps in non-ideal conditions, or were not eaten immediately after preparation. The opportunities for contamination of the food, incomplete cooking and growth of bacteria were numerous.

Centralization: The economies of scale lead to evolution of very large manufacturing operations with huge distribution networks. Smaller companies are squeezed out of the market. If something goes wrong in this supply chain, the impact can be widespread. In 2000, Staphylococcus aureus bacteria built up in raw milk that was unable to be cooled for several hours after fat separation in Snow Brand's Taiki factory. Ultimately, at least 14,700 people, mostly in western Japan, were affected by food poisoning after consuming milk or related products made by the company. Topps Meat Company, a US company specializing in manufacture of frozen ground beef, recalled 21.7 million pounds of ground beef, bringing the total recalls in the US between April and October 2007 to over 30 million pounds of red meat, mostly hamburger. The reason was that there had been a number of cases of Escherichia coli O157:H7 infection tied to its products. There was evidence of an inability to identify unique batches of product and this probably contributed to the size of the recall. The USDA also cited the company for “inadequate process controls in the non-ground meat production line”.

Ignorance may play a part. Last Easter in New Zealand, 22 people were poisoned, some seriously, when they consumed comb honey which had been made by bees that collected honeydew from tutu plants (Coriaria arborea) infested by vine hoppers. The upshot was that the honey contained large amounts of the toxin tutin, which is found in the sap of the tutu plant. In April last year, I wrote that this was not a new problem. See here Indeed, F.S. Fastier, Roslyn Emeritus Professor of Pharmacology at University of Otago, wrote last week that he was present at a meeting of interested parties in Wellington in 1964, where the issue was debated. Beekeepers have known how to manage this hazard for a long time, but a small beekeeping operator last year apparently failed to take account of the fact that there were tutu bushes in flower in the bees’ foraging area and continued to sell the comb honey. The resulting poisonings have led to the New Zealand Food Safety Authority introducing legislation to limit the amount of tutin that may be present in honey offered for sale. See here
This has not pleased everyone – some think the regulations don’t go far enough, some in the industry consider them to be unnecessary. However, NZFSA could not stand by and do nothing without risking the health of the population and the future of the lucrative New Zealand honey industry. The regulations will be reviewed at the end of the 2009 season.


In Part 2: click here:  Globalization and Greed

Guaranteed safe (?) At what cost?

You may have read of the shocking toll taken by Escherichia coli O157:H7 in the U.S. and the apparent increasing incidence of the disease. E. coli O157:H7 infection often causes severe bloody diarrhoea and abdominal cramps that may last for 5 to 10 days. In some people, particularly young children and the elderly, the infection can also cause haemolytic uremic syndrome (HUS), in which the red blood cells are destroyed and the debris causes kidneys failure. About 8% of patients may develop HUS. Sometimes the patients recover after a long illness, but a significant number of children have required kidney transplants.

Topps Meat Company, a US company specializing in manufacture of frozen ground beef, initially recalled 330,000 pounds of beef hamburger patties because of E. coli contamination. There had been a number of cases of O157:H7 infection tied to its products. On the 29th September, the company extended the recall to 21.7 million pounds of ground beef, bringing the total recalls in the U.S from April this year to over 30 million pounds of red meat, mostly hamburger. A week later, the company announced that it was going out of business, citing inability “to overcome the reality of a recall this large”.

Clearly, 21.7 million pounds is more than a single day’s production, so there is some sort of systemic failure in the plant. An inability to identify unique batches of product probably contributed to the size of the recall. The USDA also cited the company for “inadequate process controls in the non-ground meat production line”.

The recall highlights the problem of regulations based on product testing. In the US, E. coli O157:H7 is regarded as an adulterant; there is zero tolerance for its presence, so if it is found, the whole product lot must be withdrawn. However, it is extremely difficult to demonstrate total absence of a micro-organism from a product – even with large numbers of samples, it is highly likely that a low-level non-homogeneous contamination would be missed. I am told that the product in question had actually passed two levels of testing and that the recall began only when consumers became ill.

The problem is compounded by the predilection of Americans for consumption of hamburgers cooked rare. Doug Powell at Kansas State University has said many times (and again today) that colour is a poor indicator of sufficient cooking and that consumers should use a meat thermometer. Nobody should be made ill by the food they consume and no company has a right to claim that their small size should exempt them from running properly controlled safe production processes, but consumers must take some responsibility for their own safety. At least one of the consumers who contracted the O157:H7 infection admitted that she had cooked the burgers until they were pink inside.

Raw ground meat is inherently hazardous – it is manufactured from animals that may carry bacteria capable of causing human disease. It is almost impossible to guarantee that some of these bacteria will not be found on the carcase. When the meat is ground, the exterior surfaces and interior tissues are all mixed together, spreading the contamination throughout the meat. (That’s why you can cook a steak rare and produce a beautiful, safe meal, but cooking ground meat rare can leave the pathogens in the centre undamaged and capable of causing illness).

The whole thing is getting out of hand in the US. Companies are recalling huge amounts of food, the authorities are closing processing plants, lawyers are suing for massive damages and consumer advocates are calling for guarantees that food is safe. The result can be only a loss of confidence in the food supply and an increase in costs to the consumer. I see some parallels developing in the case of Campylobacter in poultry in New Zealand

From the industry point of view, the answer lies in greater process control based on a thorough risk analysis, not on discredited end product testing.