Preventing the spread of germs

It is essential to keep work surfaces and fridges clean to prevent the spread of bacteria.

Cleaning

Right now, your hands could be carrying germs – thousands of them. They're invisible, and can easily spread onto food, making you and your loved ones ill.

Stop the invasion before it's too late! Keep yourself and your kitchen clean by washing and drying your hands thoroughly:

  • before preparing food
  • after touching raw food, especially meat and vegetables
  • after going to the toilet

Make sure you keep worktops, chopping boards and utensils clean. If they’ve been touched by raw food such as meat, poultry, vegetables or eggs, you'll need to wash them thoroughly.

Don't forget to change dish cloths and tea towels regularly. They may look clean, but they're the perfect place for germs to breed. Don't let the germs win.

Killer fact

Harmful germs spread more easily on damp hands. Keep yourself and your family safe by drying washed hands thoroughly.

Cooking

Germs such as salmonella and E. coli are waiting to strike at any time. However, they can be killed by thorough cooking:

  • always follow the instructions on the label
  • always check your food is steaming hot in the middle – there should be steam coming out
  • don't reheat food more than once
  • when reheating, take extra care your food is cooked all the way through

It's especially important to make sure poultry, pork, burgers and sausages are cooked all the way through. If there's any pink meat or the juices have any pink or red in them, germs could be lurking. So stop them.

Some meat, such as steaks and joints of beef or lamb, can be served rare as long as the outside has been properly cooked.

Killer fact

Food poisoning cases double during the summer months. Cook your burgers and sausages until there is no pink meat left and they are steaming hot throughout.

Chilling

To us, it's a fridge. To some harmful germs, it's a living hell – so stop them growing by keeping them cold. And make sure you put the right foods in the fridge – look out for a 'use by' date or 'keep refrigerated' on the label.

Your fridge is a superb weapon in the battle against germs, but it must be used effectively. Here are a few useful things to remember:

  • keep it at the right temperature (between 0°C and 5°C)
  • keep the fridge door closed as much as possible
  • wait for food to cool down before you put it in the fridge
  • if your fridge is full, it might need your help - turn the temperature down to help it fight germs

Despite all that, some germs can grow at cold temperatures – even in the fridge. To help keep your food safe, eat leftovers within two days.

Keep food out of the fridge for the shortest time possible and when you're eating outside at a barbecue or picnic, use a cool bag or cool box.

If you're putting out food for a party, try not to leave it out for more than four hours. Otherwise germs might have a party of their own.

Killer fact

Outside the fridge, just 10 invisible germs can multiply to 1,000 in six hours. Keep your family's food in a cool bag or cool box when you're eating outside.

Cross-contamination

This is the final operation in the battle against germs. They mustn't be allowed to spread around your kitchen and invade food that's ready to eat. This is one of the major causes of food poisoning.

But here are a few simple things you can do to help stop it happening:

  • keep raw food such as meat, poultry and vegetables separate from ready-to-eat food
  • don't let raw meat drip onto other food – keep it in sealed containers at the bottom of your fridge
  • never use the same chopping board for raw food  and ready-to-eat food without washing the board (and knife) thoroughly in between
  • don't wash meat before cooking it. Washing doesn't get rid of harmful germs – only proper cooking will. You also run the risk of splashing germs onto worktops and utensils
  • unless packaging around vegetables says ‘ready-to-eat’ you must wash, peel or cook them before consuming

Killer fact

Salmonella can easily be spread around your kitchen. Help protect your family by keeping raw meat and poultry in covered containers at the bottom of the fridge.

Look out for listeria

If you’re over 60, pregnant, or if you aren’t well or have a long-term medical condition, you’re at higher risk from listeria. So make sure you avoid it by taking a closer look in your kitchen.

How to avoid listeria

The 'use by' date

You will see 'use by' dates on food that goes off quickly. Given the chance, listeria bacteria will grow rapidly in your food, so make sure you store it in the fridge and eat, cook or freeze it by the 'use by' date shown on the label.

Even if the food looks and smells fine, using it after the 'use by' date could put your health at risk. Don't take the chance, throw it out.

And remember, the 'use by' date is different from the 'best before' date, which you'll also see on some food labels. The 'best before' date is more about the quality of the food rather than its safety. Once food is past its 'best before' date it doesn't mean it will make you ill, but you might find that it starts to lose its flavour and texture.

The temperature of your fridge

Make sure your fridge is cold enough because this will help stop food poisoning bacteria like listeria from growing in your food. Your fridge should be between 0ºC and 5ºC (32ºF and 41ºF).

If you’re not sure how the temperature setting or dial works on your fridge, you could use a fridge thermometer to check it’s the right temperature.

The storage instructions for your food

Food that goes off quickly usually has storage instructions on the label that say how long you can keep the food and whether it needs to go in the fridge.

This sort of food often has special packaging to help keep it fresh for longer. But, once you open it, the food will go off quickly.

This is why the storage instructions also tell you how long the food will keep once the packaging has been opened. For example, you might see ‘eat within two days of opening’ on the label.

You can keep some foods for longer if you freeze them, as long as you freeze them before the ‘use by’ date.

Always check and follow any storage instructions on the label carefully.

What is listeria?

Listeria is a type of food poisoning bacteria that can live and grow in food – chilled food in particular, for example pâté, cooked sliced meats, soft cheeses and smoked fish.

You might already know that pregnant women need to avoid certain foods because they can contain listeria, but the fact is that anyone over the age of 60 is also at a higher risk from listeria. The same is true for anyone who is ill or who has a long-term medical condition.

The number of cases of listeria in people over 60 has doubled in the past nine years. And one in three of the people who get food poisoning caused by listeria die as a result.

Food bugs

Some types of bacteria in food can give us food poisoning. Check out how this happens and which bugs cause which symptoms.

What happens in the body ?

When you eat food containing certain types of bacteria, these bacteria – or the chemicals they produce – can give you food poisoning.

When you swallow the bacteria you will start to see symptoms after a delay called the ‘incubation period’. This delay is because most bacteria that cause food poisoning need time to multiply in the intestine.

The length of the incubation period depends on the type of bacteria and how many have been swallowed. It could be as little as a few hours or as much as several days.

Because the bacteria enter the body through the digestive system, generally this is the part of the body where the symptoms appear. So you might get nausea, vomiting, abdominal cramps and diarrhoea, or a combination of these. In some cases, food poisoning can cause very serious illness or even death.

When the bacteria get into your body, they stick to the lining of the intestine and destroy the cells there, either by sheer weight of numbers or by the toxins (poisons) they produce. Sometimes these toxins are absorbed and cause damage elsewhere in the body.

Some bacteria produce toxins when they grow in food. Because the toxins themselves are harmful, the bacteria don't need to multiply in the intestine to make you ill, so the symptoms come on very quickly.

How bacteria grow

Bacteria need warmth and moisture to grow – that’s why we need to keep certain foods nice and cold in the fridge. Bacteria reproduce by dividing themselves, so one bacterium becomes two, two become four, and so on.

In the right conditions, one bacterium could become several million in eight hours and thousands of million in twelve hours.

This means that if a food is contaminated with a small number of bacteria and you leave it out of the fridge overnight, it could be seriously contaminated by the next day. Then just one mouthful could make you ill. If you put food in the fridge it will stop bacteria from multiplying.

Since you can't see, taste or smell bacteria, the only way you can be sure that food is safe is to follow good food hygiene at all times.

About the bugs – campylobacter, clostridium, salmonella, listeria and E.coli

Campylobacter

Campylobacter is the most common identified cause of food poisoning. It’s found mainly in poultry, red meat, unpasteurised milk and untreated water.

Although it doesn't grow in food, it spreads easily, so if you’re not careful only a few bacteria in a piece of raw chicken could spread onto food that is ready-to-eat and cause food poisoning.

So make sure you keep raw meat separate from ready-to-eat food and always cook food properly to kill any bacteria that might be in it.

What are the symptoms?

diarrhoea, which can be severe and bloody, with abdominal cramps
vomiting is very rare

Clostridium perfringens

Clostridium perfringens is found at low levels in many types of food, particularly meat and poultry, and products made out of them. It’s also found in the soil, people’s intestines and animal intestines, in sewage and in animal manure.

Unlike many other types of bacteria that cause foodborne disease, Clostridium perfringens isn't completely destroyed by ordinary cooking. This is because it produces spores that can resist heat.

The bacteria are killed by cooking, but the heat-resistant spores they produce can survive and the heat might actually make the bacteria grow. If the food isn’t eaten at once, but is allowed to cool slowly, the bacteria that are produced when the spores germinate multiply rapidly.

Unless the food is reheated so that it’s steaming hot , the bacteria will survive.

After the bacteria have been eaten, if there are enough of them, the bacteria will produce toxins and the toxins will cause symptoms.

Foods most likely to be associated with Clostridium perfringens food poisoning are those that are cooked slowly in large quantities and left to stand for a long time at room temperature.

So make sure you cool food as quickly as possible (ideally within one to two hours) and store it in the fridge. You can help food cool down more quickly by dividing it into smaller portions.

What are the symptoms?

  • diarrhoea and severe abdominal pain
  • occasionally causes nausea
  • vomiting or fever are rare

Salmonella

Salmonella is the second-most common cause of food poisoning after campylobacter. It has been found in unpasteurised milk, eggs, products containing raw egg, meat and poultry. It can survive if food isn’t cooked properly.

Salmonella can grow in food – unless the food is chilled. There only need to be a small number of bacteria in a food for them to multiply.

People infected with salmonella should be particularly careful with personal hygiene because they could infect anyone who comes into direct contact with them. For example, if someone with salmonella doesn't wash their hands properly after going to the toilet, they could have bacteria on their hands.

What are the symptoms?

  • diarrhoea
  • vomiting
  • fever
  • abdominal pain

Listeria

Listeria or Listeria monocytogenes can cause illness in certain groups of people, such as pregnant women, unborn and newborn babies, and anyone with ‘reduced immunity’ particularly the over 60s.

People with reduced immunity include people who've had transplants; are taking drugs that weaken the immune system; or with cancers affecting their immune system, such as leukaemia or lymphoma. Among these vulnerable groups, the illness is often severe and can be life-threatening.

Listeria has been found in certain chilled ready-to-eat foods, such as pre-packed sandwiches, butter, cooked sliced meats, smoked salmon, soft cheeses and pâtés.

Anyone in these vulnerable groups should avoid eating soft cheeses such as Camembert, Brie or chevre (a type of goats' cheese), or other cheeses that have a similar rind (whether they’re pasteurised or unpasteurised), soft blue cheeses, and all types of pâté, including vegetable pâté.

Take special care to follow the storage instructions on food labels. Your fridge should be between 0°C and 5°C – and chilled foods should be kept out of the fridge for the shortest time possible. Don’t use food after its 'use by' date.

What are the symptoms?

  • flu-like symptoms (high temperature, muscle pain and can include nausea and diarrhoea)
  • severe cases can cause blood poisoning and meningitis, symptoms include severe headaches, stiff neck, confusion, fits, lack of physical co-ordination
  • can cause spontaneous abortion or stillbirth in pregnant women

Check listeria

Listeria can be a killer. So take a closer look before you prepare your food and stay safe.

  • don’t use food past its ‘use by’ date
  • make sure your fridge is between 0ºC and 5ºC (32ºF and 41ºF)
  • follow the storage instructions on food labels

E.coli

Most strains of E.coli are harmless, but the strain called E.coli O157 can cause severe illness. This is because it can produce toxins (called verocytotoxins). In other countries different strains that produce these toxins are more common, such as E.coli O111 and E.coli O26.

E.coli O157 (and other similar toxin-producing E.coli) are transmitted through eating, drinking or contact with undercooked minced beef and milk that is unpasteurised, hasn’t been pasteurised properly, or has been contaminated after pasteurisation.

It's also possible to become infected by direct contact with people or animals that are infected, or with land contaminated with animal faeces.

What are the symptoms?

  • bloody diarrhoea and abdominal cramps
  • can have very serious complications, including kidney failure, severe anaemia and neurological problems
  • can sometimes lead to death

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