The Healthy Food Guide team believe that making small diet and lifestyle changes brings the best long-term gains. We look at the science behind the headlines and promote a balanced way of eating.

Following an outbreak of this food poisoning bug, we look at how food prep and hygiene habits can lower your chances of infection.

Hot weather and outdoor eating cause food poisoning cases to soar in summer. Undercooked barbecue meats and fish are the most common culprits, says the Food Standard Agency. However this month an outbreak of e coli has been linked to pre-packed salads. In a short space of time 150 people have been infected with the most common strain E. coli 0157 and two people have died. Imports of rocket from the Mediterranean added to bagged salads are thought to be the main source.

Public Health England advises: ‘People can help protect themselves from possible infection by washing their hands before eating and handling food and by thoroughly washing vegetables and salads that they are preparing to eat (unless they have been pre-prepared and are specifically labelled ‘ready to eat’).

The symptoms

Stomach cramps, diarrhoea that may contain blood and, in severe cases, kidney failure. Symptoms usually develop between three and four days and last for two weeks. The 0104 strain causes bloody diarrhoea and may lead to haemolytic uraemic syndrome, which can cause acute kidney failure and death.

How to treat it

NHS Choice says there is no specific treatment for E. coli O157 infection, and that people who are infected can usually be cared for at home and most will get better without medical treatment. However it advises you do the following:

* It is important to drink plenty of fluids, as diarrhoea can lead to dehydration.

* You should contact your GP or call NHS 111 as soon as possible if you or your child has bloody diarrhoea.

* Antibiotics are not recommended, and may increase the risk of complications.

* Anti-diarrhoea drugs such as loperamide (Imodium) are also not recommended as they may prolong your exposure to the toxin.

How to avoid E. coli infection

Refresh your food hygiene habits with Public Health England’s checklist

*Wash hands thoroughly after using the toilet, before and after handling food, and after handling animals

* Remove any loose soil before storing vegetables and salads

* Wash all vegetables and fruits that will be eaten raw

* Store and prepare raw meat and unwashed vegetables away from ready-to-eat foods

* Do not prepare raw vegetables with utensils that have also been used for raw meat

* Cook all minced meat products, such as burgers and meatballs, thoroughly

* People who have been ill should not prepare food for others for at least 48 hours after they have recovered

Other common food poisoning strains:


The most common cause of food poisoning, this is responsible for about 80% of all cases.

Food sources

Raw or undercooked meat or poultry and unpasteurised milk are the main culprits. Chicken is the most common source in the UK – the FSA is working with the poultry industry to reduce the incidence of campylobacter
in chickens.

The symptoms

Fever, headache and generally feeling unwell, followed by severe stomach cramps and diarrhoea, which may contain blood. Vomiting is rare. Symptoms normally start between two and five days after eating but may take as long as 10 days to appear. It can last for one to seven days and symptoms can also recur about three weeks after the first symptoms develop.


This is the second most common cause of food poisoning.

Food sources

It’s found in many foods, especially raw meat, poultry, shellfish, unwashed
raw vegetables, unpasteurised milk and eggs. However, eggs that bear the Lion Quality mark come from hens that have been vaccinated against salmonella.

The symptoms

Fever, diarrhoea, vomiting and stomach pain. It can cause particularly severe illness in very young or old people or those who are already unwell. Symptoms come on between 12 and 36 hours after eating, although they can sometimes be experienced as early as six hours or as late as 72 hours, and they usually last for one to eight days.


This is a virus (rather than a bacterium) and is a particular problem on cruise ships and in nursing homes and hospitals as it can quickly spread from person to person and through handling contaminated food, water or objects.

Food sources

Raw or undercooked shellfish and chilled foods like salads and sandwiches can contain this virus. Fortunately, norovirus doesn’t multiply in food, as many bacteria do, and thorough cooking destroys it, so good food and personal hygiene can help prevent it.

The symptoms

Infection causes nausea, vomiting, diarrhoea, fever, headache, aching limbs and stomach pain within one to two days after being infected, although symptoms can start within 12 hours. They generally last around two days.