Typically, children catch E.Coli O157 visiting farms and petting zoos, where basic safety precautions such as washing hands with hot water and soap can prevent infection. Where people are infected in restaurants, the cause is often poor storage of food, cross-contamination and poor hygiene generally.
Public Health England (PHE) offers the following information as background to Escherichia coli (E. coli) O157 infection:
"Escherichia coli (E. coli) bacteria can live in the intestines of healthy people and animals without causing any illness. Other types of E. coli can cause illness in people and among these is a group of bacteria which are known as Shiga toxin-producing E. coli or STEC.
E. coli O157 are the commonest type of STEC bacteria in the UK. These bacteria cause infections with a broad range of clinical presentations; from no symptoms, through to mild diarrhoea and to severe bloody diarrhoea. In addition, two serious complications may arise - haemolytic uraemic syndrome (HUS) and thrombotic thrombocytopaenic purpura (TTP). These complications affect the blood, kidneys and brain and can be fatal, particularly in infants, young children and the elderly.
Infection occurs when people get E. coli O157 bacteria in their mouth and this can happen through:
- consuming food or drink that is contaminated with E. coli O157 bacteria – including raw or undercooked meat, foods contaminated with E. coli O157 from contact with raw meat, faeces from infected animals or faeces from infected people;
- hand-to-mouth transmission following contact with faeces from a person with E. coli O157 infection or contact with an object or the environment contaminated with faeces by an infected person;
- putting an object in the mouth that has been contaminated with faeces from an infected person or animal;
- hand-to-mouth transmission following contact with animals that carry E. coli O157 or an environment contaminated with animal faeces, such as a farm.
The incubation period is the time from being exposed to the bacteria to the time that symptoms start. The incubation period for E. coli O157 is usually three to four days but has been recorded as anywhere between one and 14 days.
E. coli O157 infection is highly infectious and ingesting ten to 100 bacteria can cause human illness. The infection can spread easily within households and in other settings such as day nurseries, primary schools, nursing homes and hospitals. E. coli O157 bacteria can survive for a long time in the environment.
Cattle are the most common reservoir of E. coli O157 in the UK although STEC have also been found in the faeces of a wide range of animals including sheep, goats, deer, rabbits, horses, pigs and wild birds. E. coli O157 cause no symptoms in animals but they can carry the infection for long periods and shed E. coli O157 in their faeces."
Claire's case involves a then 9-year-old child (AB) who visited a farm in Cambridgeshire on a school trip and then again with family. AB remembers feeding the lambs. Shortly afterwards, AB became very unwell and her parents took her to hospital. She was discharged home but later that night her symptoms worsened and on return to hospital it was apparent her kidneys were failing. She was put onto dialysis in hospital for approximately one week.
AB had contracted haemolytic uraemic syndrome (HUS) as a result of E.Coli O157. HUS is the most significant complication of infection by E.Coli O157 and can occur when the infection causes the kidneys to fail. HUS can lead to very serious complications including high blood pressure, heart failure, diabetes, seizures, coma, and, in severe cases, brain damage.
Several years after the farm visit, AB has been left with ongoing symptoms for which she continues to receive treatment. What is extremely worrying for her and her family are what the future impact of the infection on her health will be. Her kidney function will be need to be tested regularly in hospital to monitor this.
Claire said 'Unfortunately, the consequences of infection with E.Coli O157 may be much longer lasting than the initial painful and unpleasant symptoms of abdominal pain and diarrhoea. There can be debilitating ongoing problems with abdominal pain, bowel control, kidney function and bladder control. In some cases, there is permanent neurological damage, and of course the trauma of the acute illness and the invasive hospital treatment can have its own psychological and behavioural consequences, such as anxiety or phobia of medical treatment. It can be particularly distressing for children who become infected and have to deal with any, or a combination, of these ongoing symptoms'.
Harvinder was instructed by the family of a teenage girl, Sally*, who contracted E.Coli O157 and associated HUS after eating in a local pub in Sunderland to celebrate a birthday. A few days later, she woke up in the night with stomach pain, followed by vomiting and bad diarrhoea, which contained blood. She went to her GP and was sent straight to A&E. She was in terrible pain. Initially the hospital considered appendicitis and Chron's disease but test then revealed it was E.Coli O157. She needed morphine to control the pain and, at times, was unable to wake up.
The impact on Sally's life has been terrible. She is a high achiever at school but her education has been badly affected by having to having to take so much time off school. She is understandably wary of food which has caused her to lose weight, and the whole family are too worried to eat out in restaurants, preferring to eat at home.
While the girl was in hospital, a then 18 month-old was admitted with similar symptoms, having eaten at the same restaurant. The family has also instructed Harvinder. This young boy has been left with a reduced kidney function meaning he has had to follow a special diet and requires close monitoring. He has also developed seizures which are currently under investigation.
In each of these three cases, Fieldfisher has issued a letter of claim for personal injury against the insurers of the premises involved and works in parallel with investigations by Public Health England to identify the source of the infection but also to ascertain whether there is corporate negligence involved in failing to keep people safe.
An additional concern for all families involved is uncertainty of the impact of the infection on their children as they grow up. At the very least, they face regular and ongoing hospital tests and live under the stress of potential long-term health problems. In some circumstances it is appropriate to consider the settlement of these cases with a Provisional Damages Order, meaning that the clients can re-open their cases in the future if they develop one of the identified risks.
Following investigation by PHE, the at-fault premises must undertake processes as instructed to prevent further infection and must comply with guidelines set out to keep the public safe.
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