The Food Standards Agency has recently updated its guidance on the control of cross-contamination relating to E. coli 0157 bacteria. Its original guidance was published following an investigation into the outbreak of E. coli 0157 in South Wales in September 2005, where 157 cases were identified. The majority of these were schoolchildren, one of whom died.
It is believed that the bacteria entered the children’s digestive system via cooked cold meat served for school meals. The source of the infection was traced back to poor hygiene practices at the abattoir supplying meat to the caterers.
The latest FSA guidance has been revised following independent research into the effectiveness of disinfecting complex equipment, and takes into account the views of industry and local authority stakeholders. It gives greater flexibility to individual businesses on how they manage food safety risks, but is also subject to subsequent assessment by the relevant local authority to ensure that cleaning between uses will provide effective controls.
The main points of the revision
- If businesses can demonstrate that cross-contamination can be managed by time and effective cleaning and disinfection, then they do not need to have separate areas for handling raw and ready-to-eat (RTE) foods.
- Provided that businesses can demonstrate the effective cleaning and disinfection of equipment such as mixers, weighing scales and temperature probes between uses, then the same equipment can be used for raw and RTE foods.
- The third major revision concerns the effective cleaning and disinfection of more complex equipment such as mincers, slicers and vacuum packers to enable the same equipment to be used for both RTE and raw foods. In this case the equipment would need to be completely dismantled to allow all surfaces to be thoroughly cleaned.
In practice it is unlikely that businesses would want to start dismantling and cleaning mincers etc. during normal operations. Similarly the dismantling, cleaning and reassembly of vacuum packers is a complicated process requiring a competent engineer so it is doubtful that businesses would wish to undertake this.
Any disinfectants and sanitisers used to clean equipment and surfaces must meet officially recognised standards and should always be used as instructed by the manufacturer. Additionally handwashing should be carried out using a recognised technique:
- Wet hands, apply soap and rub palms together until soap is bubbly
- Rub each palm over the back of the other hand
- Rub between your fingers on each hand
- Rub backs of fingers (interlocked)
- Rub around each of your thumbs
- Rub both palms with fingertips, then rinse
- Dry your hands well on a clean, dry towel or paper towels
N.B. The use of anti-bacterial gels should not be a substitute for thorough handwashing.
How does E. coli infection occur?
E. coli 0157 bacteria are commonly found in the gut of cattle and other farm animals, so there are various ways in which they can be passed into the food we eat. For instance, if effective food safety practices have not been followed at abattoirs or in meat processing plants the meat can become infected. Or if the milk or cheese we eat is unpasteurised there is a higher risk than if it has been pasteurised.
Also, since E coli lives in animals’ guts, it is present in their faeces and can pass into soil or water supplies. Thus, the saying that ‘a little bit of dirt won’t do you any harm’ is not necessarily true.
This is why there have been outbreaks of E. coli in recent years relating to vegetables such as beansprouts and watercress. It has also emerged that there was an 8 month E coli outbreak across the UK in 2011 where 250 people became ill and one died. The outbreak was eventually traced to handling leeks and potatoes bought loose. So even though food producers have good systems in place to clean vegetables and fruit, the risks can never be entirely eliminated. It is always best to wash any fruit or veg yourself before eating them.
A few E. coli bacteria can cause a lot of trouble…
The thing is that only a very few E. coli bacteria are needed to cause an infection. The symptoms can range from mild stomach upsets to severe stomach cramps, bloody diarrhoea, vomiting and fever. In extreme cases it can cause complications such anaemia and kidney failure and even death. Complications such as these are much more common in vulnerable people; for instance, the under-fives, the elderly and those whose immune system is already down through other illness.
Other ways in which E coli can be transmitted is through swimming in contaminated water or drinking water from rivers or streams which has not been boiled or purified (see our blog on food safety when camping). You can also get infected through poor personal hygiene of someone who already has food poisoning – if they don’t wash their hands properly after using the toilet and then go on to prepare food or touch surfaces or equipment.
Make sure you prevent cross-contamination
As we mentioned at the beginning of this article E-coli is present on raw meat, so it’s essential that raw meat and ready to eat foods, such as cooked meats, salads etc. are processed separately and stored appropriately and effectively in the fridge. Don’t use the same plates, chopping boards, knives, surfaces etc. without thoroughly washing in between uses.
If you work in an environment where food is prepared and you have any of the symptoms of food poisoning, you should inform your manager and stay off work until you feel completely better and your stools have returned to normal. This also applies to people working with the elderly and babies and infants.
The Health Protection Agency also recommends that you wash all dirty clothes, bedding and towels on the hottest cycle of the washing machine. In addition you should clean toilet seats, bowls and handles, as well as taps and basins after use with detergent and hot water, followed by a household disinfectant.
Our Level 3 online food safety course goes into detail about the cause and prevention of cross-contamination, to find out more, please click here.