E. coli O157, England and Wales

I am fascinated with viruses, and we’re all hosts on a viral planet.

We used whole-genome sequencing to investigate the evolutionary context of an emerging highly pathogenic strain of Shiga toxin–producing Escherichia coli (STEC) O157:H7 in England and Wales.

A timed phylogeny of sublineage IIb revealed that the emerging clone evolved from a STEC O157:H7 stx-negative ancestor ≈10 years ago after acquisition of a bacteriophage encoding Shiga toxin (stx) 2a, which in turn had evolved from a stx2c progenitor ≈20 years ago. Infection with the stx2a clone was a significant risk factor for bloody diarrhea (OR 4.61, 95% CI 2.24–9.48; p<0.001), compared with infection with other strains within sublineage IIb. Clinical symptoms of cases infected with sublineage IIb stx2c and stx-negative clones were comparable, despite the loss of stx2c. Our analysis highlighted the highly dynamic nature of STEC O157:H7 Stx-encoding bacteriophages and revealed the evolutionary history of a highly pathogenic clone emerging within sublineage IIb, a sublineage not previously associated with severe clinical symptoms.

Highly pathogenic clone of shiga toxin-producing Escherichia coli O157:H7, England and Wales, December 2018

Emerging Infectious Diseases vol. 24 no. 12

Lisa Byrne, Timothy Dallman, Natalie Adams, Amy Mikhail, Noel McCarthy, and Claire Jenkins


Salmonella sample swap: Welsh biologist used patient’s poo to get time off work

Philip Dewey and Jessica Walford of Wales Online report a scientist who didn’t want to work day shifts swapped his own feces with a patient who had salmonella to prove to his bosses he had food poisoning.

Bernard Watkins worked as a biomedical scientist in the microbiology department at Cwm Taf University Health Board.

After he was handed day shifts, instead of his preferred night shifts, he went into a freezer at work and took a patient sample which had tested positive for salmonella before using a computer at work to check a patient’s confidential details and make sure they had the disease.

But days later he confessed all to one of his bosses – admitting he had “spiked” his sample.

Mr Watkins was due to appear before a conduct and competence panel of the Health and Care Professions Council (HCPC) for allegations of dishonesty, misconduct and whether his fitness to practise has been impaired, but the hearing was held in his absence.

The panel heard on Thursday how on October 10, 2016, Mr Watkins, who had 20 years service at the time, told his bosses he was unable to come into work as he feeling unwell and suffering from diarrhoea and vomiting.

He left a fecal sample in the office on the same date.

Two days later, on October 12, he called his employers to say he wouldn’t be working for the rest of the week as he remained unwell.

The same day the fecal sample tested positive for salmonella.

One of his bosses, Kelly Ward, the manager for Microbiology, phoned Mr Watkins and asked him to submit another fecal sample signed by his GP.

On October 13 Mr Watkins explained to Mrs Ward he had been to his GP and provided the sample. But the sample tested negative for salmonella.

On October 17 Mr Watkins returned to work and Mrs Ward completed a return to work form. She discussed concerns with him going off work when he was required to work day shifts instead of his preferred night shifts.

But just two days later, as Mr Watkins was finishing a night shift which ended at 8am, he called Mrs Ward and asked to meet her when she got into work.

He told her he “deliberately contaminated” a sample of a patient who had salmonella with his own feces by adding in his own fecal matter, saying his employer would have “found out anyway”.

4 sick with campy linked to raw milk served at Royal Welsh Show

In 2013, at least 50 people, mainly children, became ill with E coli O157 at the Ekka, Queensland, Australia’s version of the state fair.

It starts again on Friday, and because organizers have done little except to encourage people to wash their hands, we won’t be going.

Handwashing is never enough.

Manure from ruminants is easily aerosolized in these environments, and I’ve been to many human-animal interaction events for research, and there is shit everywhere.

Although ostensibly designed to promote understanding of food production, these agricultural celebrations rarely discuss risk – until an outbreak happens.

The motto seems to be: It’d be better for us if you don’t understand.

Now, four people have been sickened with Campylobacter linked to unpasteurised or raw cow’s milk from Penlan y Môr farm near New Quay, Ceredigion and sold at the Royal Welsh Show.

Public Health Wales says the four cases all consumed or bought the milk at Aberystwyth Farmer’s Market after June 1.

But visitors to the Royal Welsh Show in Builth Wells may also have sampled or bought the milk which was available there on Wednesday, 26 July.

A table of animal-human-interaction outbreaks is available at https://www.barfblog.com/wp-content/uploads/2017/08/Petting-Zoo-Outbreaks-Table-7-26-17.xlsx

Erdozain G, Kukanich K, Chapman B, Powell D. 2012. Observation of public health risk behaviours, risk communication and hand hygiene at Kansas and Missouri petting zoos – 2010-2011. Zoonoses Public Health. 2012 Jul 30. doi: 10.1111/j.1863-2378.2012.01531.x. [Epub ahead of print]

Observation of public health risk behaviors, risk communication and hand hygiene at Kansas and Missouri petting zoos – 2010-2011Outbreaks of human illness have been linked to visiting settings with animal contact throughout developed countries. This paper details an observational study of hand hygiene tool availability and recommendations; frequency of risky behavior; and, handwashing attempts by visitors in Kansas (9) and Missouri (4), U.S., petting zoos. Handwashing signs and hand hygiene stations were available at the exit of animal-contact areas in 10/13 and 8/13 petting zoos respectively. Risky behaviors were observed being performed at all petting zoos by at least one visitor. Frequently observed behaviors were: children (10/13 petting zoos) and adults (9/13 petting zoos) touching hands to face within animal-contact areas; animals licking children’s and adults’ hands (7/13 and 4/13 petting zoos, respectively); and children and adults drinking within animal-contact areas (5/13 petting zoos each). Of 574 visitors observed for hand hygiene when exiting animal-contact areas, 37% (n=214) of individuals attempted some type of hand hygiene, with male adults, female adults, and children attempting at similar rates (32%, 40%, and 37% respectively). Visitors were 4.8x more likely to wash their hands when a staff member was present within or at the exit to the animal-contact area (136/231, 59%) than when no staff member was present (78/343, 23%; p<0.001, OR=4.863, 95% C.I.=3.380-6.998). Visitors at zoos with a fence as a partial barrier to human-animal contact were 2.3x more likely to wash their hands (188/460, 40.9%) than visitors allowed to enter the animals’ yard for contact (26/114, 22.8%; p<0.001, OR= 2.339, 95% CI= 1.454-3.763). Inconsistencies existed in tool availability, signage, and supervision of animal-contact. Risk communication was poor, with few petting zoos outlining risks associated with animal-contact, or providing recommendations for precautions to be taken to reduce these risks.

Best practices for planning events encouraging human-animal interactions

Zoonoses and Public Health

G. Erdozain , K. KuKanich , B. Chapman  and D. Powell


Educational events encouraging human–animal interaction include the risk of zoonotic disease transmission. It is estimated that 14% of all disease in the US caused by Campylobacter spp., Cryptosporidium spp., Shiga toxin-producing Escherichia coli (STEC) O157, non-O157 STECs, Listeria monocytogenes, nontyphoidal Salmonella enterica and Yersinia enterocolitica were attributable to animal contact. This article reviews best practices for organizing events where human–animal interactions are encouraged, with the objective of lowering the risk of zoonotic disease transmission.

Hepatitis A outbreak strikes in Welsh schools

Parents are being advised not to send their child to school for seven days if Hepatitis A is suspected following a number of cases in Caerphilly, South Wales

hep.aParents are being warned over an outbreak of hepatitis across schools in the UK.

Public Health Wales have confirmed that two more cases – including one at a secondary school – have been diagnosed in Caerphilly.

The total number of cases of hepatitis A in the area is now 11.

Heather Lewis, a consultant in health protection, warned there may be more cases to come, reports Wales Online.

Hepatitis A vaccination is not routinely offered on the NHS, as the infection is rare in the UK, with 13 reported cases in Wales in 2012.

It is strongly advised that anyone travelling to a country where the infection is more common should receive the vaccination.

Scientists find ancient Welsh beer recipe that could treat food poisoning

While breweries in China may date back 5,000 years, a 16th century Welsh drink has been found to contain antibacterial properties that could help fight food poisoning.

stream_imgScientists at Cardiff University hope to create a “super mead” using a mixture of herbs that can tackle salmonella.

“We’re actually running out of antibiotics now, so it’s imperative that we identify new products that are active against these bacteria, especially the likes of salmonella and e-coli which are causing problems all over the country and indeed the world…”

– Dr James Blaxland, Cardiff University

The scientists have been trying to work out how to make a so-called ‘super honey’.

They’ve found with a mix of herbs that together can fight bacteria like salmonella.

“Back in the sixteenth century, there was a Welsh drink called metheglin. Metheglin translates into ‘healing liquor’.

Basically, it’s mead… alcoholic mead that we drink… combined with medicinal herbs.

What we are trying to do is identify those medicinal herbs that we could add to the mead to make a drink that was antibacterial.”

– Prof Les Baillie, Cardiff University

They hope combining Welsh history with science being done in Wales could lead to new and effective drugs.

Restaurant was never named but should be: 33 sickened by Campylobacter in Cardiff, 2015

Knowing when to go public in an outbreak situation is challenging. But it’s better than silence.The most important conclusions from this Public Health Wales report are:

Buffet_CounterOn the 27th May 2015 the Shared Regulatory Services Communicable Disease Team (Cardiff)  identified two cases of Campylobacter (one in Cardiff and the other in the Vale of Glamorgan) that were linked to the same premises (Premises A) in Cardiff.

This triggered an immediate investigation and an Outbreak Control Team was subsequently convened, declaring a formal outbreak on 4th June 2015.

In total there were 33 cases meeting the case definition of which 11 were microbiologically confirmed as Campylobacter jejuni. No cases were hospitalised. 24 cases ate at Premises A on 17th May. Of the remaining cases, seven ate on 16th May and one on 18th May. The final case ate on 7th June.

Repeated environmental visits were undertaken and issues that could potentially lead to cross contamination were identified. Premises A voluntarily closed on 4th June to address these issues and reopened on 6th June.

Of the 33 cases, 31 participated in a case control study.  These all ate between the 16th and 18th May.  The study revealed that 100% (31) of included cases had eaten from the salad bar compared to 84.9% (45/53) controls (p=0.024). In addition, 30 of 31 cases (96.8%) had eaten pasta salad from the salad bar, compared with 22/50 controls  (44%) (odds ratio 38; 95% CI 5.3–1611). Adjustment for other exposures using logistic regression did not materially change the association with eating pasta salad. A similar but independent association with eating noodles from the salad bar was also identified but few of the cases (6/31) had consumed noodles.

Environmental investigation found areas of non compliance with statutory food hygiene regulations and confirmed that several poor food hygiene practices had been identified that potentially could result in pasta salad cross-contamination within the kitchen area.

It was therefore concluded that eating pasta salad from the salad bar between 16th and 18th May 2015 was significantly associated with acquiring Campylobacter infection in this outbreak, and that for the small number of individuals who ate noodles this may have been independently associated with acquiring Campylobacter infection. The identification of non-meat items (often salad) in Campylobacter outbreaks is a reoccurring theme.

IMG_7739Ensuring good food hygiene is always the sole responsibility of the Food Business Operator. Nevertheless, it is important to note that this outbreak identified several issues which have implications more widely.

These included:

  • Issues with the interpretation and implementation by the food business of the Food Standards Agency E. coli O157 Control of Cross Contamination Guidance (revised December 2014).
  • Issues relating to the Primary Authority’s response in outbreak situations (relevant to Food Business Operators with multiple outlets).

The specific points of concern are explained in the discussion section of this report. 

Related to these issues, investigations highlighted three matters which may have implications for other high throughput food businesses.  These were:

  • Not using physical separation as the primary control measure to prevent cross-contamination.
  • An over reliance on two-stage cleaning as a control measure which may fail during busy periods.
  • The need to design out (as much as possible) any potential for human error resulting in cross-contamination.

Following this outbreak, improvements with respect to these three matters have been implemented in Premises A and all other similar premises nationally that are under the same ownership.

The outbreak was declared over on 25th August 2015.


  1. There were 33 cases of Campylobacter associated with this outbreak. Eleven were microbiologically confirmed.
  2. This had the features of a point source outbreak. All but one case ate at Premises A on the weekend 16-18th May. The final confirmed case ate at the premises on 7th June.
  3. Epidemiological and environmental investigation identified cross-contamination of the pasta salad as the most likely source of the outbreak for the cases on 16-18th May. No source was identified for the case on 7th June.
  4. Environmental investigation found areas of non compliance with statutory Food Hygiene Regulations and confirmed that several poor food hygiene practices had been identified that potentially could result in pasta salad cross-contamination within the kitchen area.
  5. The interpretation and application of the December 2014 revised version of the Food Standards Agency E. coli O157 Control of Cross Contamination Guidance by the Food Business Operator of Premises A resulted in the business not using physical separation as the primary control measure to prevent cross-contamination. This and over reliance on two-stage cleaning as a control measure was potentially not effective in preventing cross-contamination. This guidance was then used by the Food Business Operator to defend such arrangements and structural layouts as being in line with the recommendation of this guidance.
  6. Implementation of some control measures in this outbreak were delayed by involvement of the Primary Authority.
  7. Being unable to interview food handlers involved in this outbreak at an early stage in a structured format away from Premises A hampered outbreak investigation and control.
  8. Issuing a proactive press release without naming the premises resulted in this decision becoming the media focus rather than the outbreak.


  1. The Food Standards Agency E. coli O157 Control of Cross Contamination Guidance (revised December 2014) should be reviewed in light of the issues identified in this outbreak.
  2. The Food Standards Agency should work with the Better Regulation Delivery Office to develop advice for Primary Authorities on providing timely and effective responses to outbreak investigations.
  3. Proactive follow-up for example via telephone of all confirmed Campylobacter cases in Wales should be routine practice by all Local Authorities. This supports early detection of outbreaks, the application of control measures to be timely and prompt hygiene advice to be given to cases.
  4. Local Authorities should ensure that they retain sufficient Environmental Health staff with Food Safety and Communicable Disease skills to be able to proactively follow up communicable disease cases and investigate suspected outbreaks.
  5. Although direct poultry contact or consumption is known to be the most common source for Campylobacter infection in humans, the Food Standards Agency Campylobacter Reduction Strategy should note for consideration that outbreaks in Wales have also been linked to non meat products such as salads. This could of course in some cases represent cross contamination but they may wish to consider looking at the body of evidence from such outbreaks across the United Kingdom to inform the Strategy going forward.
  6. The use of ‘Requests for Co-operation’ under health protection legislation should be considered early in outbreak investigations in order to effectively interview food handlers.
  7. In future outbreaks proactive media engagement without naming the premises should be avoided.


It’s not a virus or bacterium, it’s a parasite: 7 positive, 16 sick with crypto after visit to Welsh petting farm

A Monmouthshire farm has cancelled a series of open day visits for primary school children following the outbreak of a diarrhea-causing virus.

powell.namePublic Health Wales along with Torfaen and Monmouthshire councils are continuing to investigate an outbreak of cryptosporidium associated with Coleg Gwent’s farm in Usk.

Seven people have tested positive for cryptosporidium and 16 others are suspected of having the bug after regular attendance at the farm or contact with those who have.

Heather Lewis, consultant in health protection for Public Health Wales, said: “We are continuing to work with Coleg Gwent, who have written to all students who may have been on the farm in March.

“As a precaution, Coleg Gwent have also cancelled a series of open days which were due to take place with invited primary schools from Tuesday, April 12 to Friday, April 15.”

A spokesman from Public Health Wales said: “Good hand washing after coming into contact with farm animals, their bedding or dirty equipment including clothing is of the utmost importance in preventing infection with cryptosporidium.

“There is no reason for anyone to avoid visiting petting farms as long as they ensure that anyone who has touched animals, thoroughly washes their hands with hot water and soap immediately afterwards and before eating, as hand sanitisers or alcoholic gels should not be solely relied upon.”

Handwashing is never enough.

Welsh farm investigated after visitors test positive for crypto

A Monmouthshire farm is being investigated after a number of visitors tested positive for a microscopic parasite that causes a diarrheal disease.

Coleg Gwent’s farm in UskPublic Health Wales, Torfaen County Borough Council and Monmouthshire County Council are investigating an outbreak of cryptosporidium at Coleg Gwent’s farm in Usk.

Three people have tested positive for cryptosporidium and eight others are under investigation after a regular attendance at the farm.

“All the confirmed cases had direct contact with the lambs at the college farm. As part of our investigations, we are checking on all those whom we believe had contact with these animals and Coleg Gwent is co­operating fully with our investigations.


Food giants’ low food hygiene ratings in Wales

KFC in Pontypool was given a zero score by the Food Standards Agency, the worst rating meaning urgent action is needed.

KFC in PontypoolCo-operative stores in Pontardawe, Porth, and Birchgrove, Cardiff scored one, along with Subway in Queen Street, Cardiff and Harvester in Cardiff Bay.

Costa in Brecon, Tesco cafe in Maesteg and Asda in Aberdare had a two rating.

That means improvement is necessary.

There are more than 26,000 businesses in Wales which have ratings, of which more than 1,400 had a two rating or below. The highest score is five.

Russel Smith, chief operating officer, KFC UK, said: “I was extremely disappointed by the rating this restaurant received, which is completely unacceptable.

“We took immediate action to return the restaurant to the standards we demand and are awaiting a re-inspection which we are sure will reflect this.”

Going public: Seven people struck by campy in UK but public health body refuses to name restaurant it closed down

Wales Online reports that a public health body says it will not name a Cardiff restaurant at the centre of a food poisoning outbreak.

wales.food.rating.19Public Health Wales says it is “satisfied” that the situation – which led to seven people being confirmed with the campylobacter infection – has been dealt with and there is “no risk to public health.”

The victims ate at the restaurant during the weekend of May 16, and two people are also suspected to have the infection.

At the end of last week, Public Health Wales, the Regulatory Service for Cardiff, the Vale of Glamorgan and Bridgend councils, Cardiff and Vale University Health Board and the Food Standards Agency said they were working together to investigate an outbreak of campylobacter with links to the restaurant.

The restaurant is not being named despite the fact that new laws require all premises dealing with food to openly display their food hygiene ratings.

Facebook user Claire Drewen said: “That is wrong! The public have a right to know. Public Health Wales should release the name. Maybe people would like to avoid the restaurant when it reopens.”

But Greg Cannon said: “Why can’t we have an intelligent debate rather than scaremongering? There is probably a very good legal as well as commercial argument for not naming; but in the age of social media all it takes is one Facebook or Twitter post and the name is known. PHW might avoid the legal case and the public still get the information they think they need.”