Yersinia Enterocolitica

This rare form of food poisoning occurs as a result of eating contaminated food, in particular undercooked pork. This results in those all too familiar symptoms of nausea, abdominal pain and diarrhoea which characterise most cases of food poisoning.

This is often known as Y. enterocolitica for short.

This type of illness affects both children and adults although children are affected more than adults. Anyone in a high risk group such as the elderly or those with a weakened immune system is also susceptible.

The yersinia enterocolitica bacteria

These bacteria form part of a larger group called the ‘enterobacteriaceae’. This group also includes the E coli and salmonella bacteria.

Other similar strains include ‘yersinia pestis’(responsible for plague) and ‘yersinia pseudotuberculosis’ (tuberculosis symptoms).

Not all strains of Y enterocolitica bacteria cause food poisoning in humans. The rod shaped bacterial strain which infects humans is found in pigs but other strains are found in cattle, horses, cats and dogs.

Causes of yersinia enterocolitica poisoning

This illness develops as a result of eating raw or undercooked pork, or pork based products. Other sources of contamination include unpasteurised milk or untreated water, or contact with an infected animal.

Another factor is person to person contact. If someone who has handled food or soil which has been contaminated by infected animal faeces, touches another person then this will transfer the infection to them.

This tends to happen if the infected person fails to wash their hands properly or shows a lack of attention to basic hygiene.

These bacteria can be transmitted to another person via a blood transfusion but this is very rare.

Symptoms of yersinia enterocolitica poisoning

These symptoms appear several days after initial contact with the bacteria, usually around 4 days to a week. They last from 1 to 3 weeks although they may persist even longer.

Symptoms include:

• Abdominal pain
• Fever
• Diarrhoea (often bloody)

Many older children and adults experience abdominal pain on the right had side of their bodies which along with fever, is often mistaken for signs of appendicitis.

Complications of yersinia enterocolitica poisoning

These occur in only a small number of cases. They include a skin rash, pains in the joints or the bacteria spread into the bloodstream and cause diseases such as arthritis.

Diagnosing yersinia enterocolitica poisoning

This involves a physical examination and a stool sample. The stool sample is a very common test in which a small sample of faeces is obtained and sent for laboratory analysis.

The yersinia enterocolitica bacteria are not usually tested at laboratories so any laboratory that receives this type of sample will have to be notified beforehand.

There are other tests that can be done to confirm a diagnosis which include blood, urine and swabs taken from the throat.

Treatment for yersinia enterocolitica poisoning

Most cases resolve themselves without the need for treatment. But if they require some extra help then bed rest and consuming plenty of liquids will help.

This will also prevent against dehydration which is always a risk in food poisoning cases, usually due to the frequent bouts of vomiting and /or diarrhoea.

One way of dealing with this is to purchase re-hydration powders from a local pharmacy. These powders contain electrolytes which are a replacement for essential vitamins and minerals which have become depleted as a result of this illness.

Antibiotics are not usually prescribed unless symptoms are severe or complications have arisen.

Preventing yersinia enterocolitica poisoning

There are a few measures you can take to prevent this illness. These include:

• Ensure that all pork is cooked at the correct temperature and cooking time. Do not eat undercooked pork.
• Wash your hands with soap and water before and after handling food.
• Use separate utensils, chopping boards and containers for raw and cooked foods.
• Store raw food away from cooked food

For more information visit our preventing food poisoning section.