Think... before you drink... unpasteurised milk

Date: 2002


Be Aware

Milk produced on farms on the island of Ireland is generally acknowledged to be of very high standard. The microbiological standards demanded of milk at EU level have been consistently improving over recent years. What you may not know, however, is that these routine tests do not specifically check for E. coli, Salmonella and other potentially harmful bacteria which may be present in unpasteurised milk. There are, therefore, potential risks associated with the consumption of unpasteurised milk and farming families who frequently drink unpasteurised milk produced on the farm should be aware of the possible risks.

Benefits of Pasteurisation

Pasteurisation is a process which destroys harmful bacteria in unpasteurised milk by heating. Milk which may have become contaminated on the farm, either directly from the animal or indirectly from the farming environment, is thereby rendered safe.

Unpasteurised Milks – The potential risks

While cattle are tested for brucellosis and tuberculosis (TB) on a regular basis, herd breakdowns can and do occur – often without warning – and families may unwittingly continue to consume unpasteurised milk without realising the potential dangers.

Who is at risk?

Anyone who drinks unpasteurised milk is at potential risk of being exposed to a number of bacteria. Those at most risk include vulnerable people such as young children, the elderly, pregnant women or those whose immunity is low. The following bacteria may contaminate unpasteurised milk at farm level:

  • Brucellosis symptoms are often flu-like; they are characterised by continued or intermittent fever, headaches, weakness, profuse sweating, joint pain, depression and weight loss.
  • Bovine TB infection causes either abdominal disease or cervical adenitis (enlarged neck glands).
  • E. coli are bacteria which are present in the intestines of humans and animals and many are not harmful. Some strains, however, such as E. coli O157:H7, produce a toxin and infection may lead to serious complications in the bowel and kidney.
  • Salmonella infection in humans may cause sudden onset of headache, fever, stomach cramps, diarrhoea, nausea and sometimes vomiting.
  • Campylobacter infections in humans may cause diarrhoea, stomach cramps, fever, nausea and vomiting.
  • Listeria infection symptoms are generally mild and flu-like. Vulnerable individuals may suffer from meningitis or septicaemia (blood poisoning). Abortion may occur in pregnant women.

How can infection be prevented?

The safest option is to drink milk that has been pasteurised. Farming families and visitors to farms are therefore strongly advised to either buy pasteurised milk for home consumption or to pasteurise their own milk with a reliable home pasteuriser.

The assistance of the Cork Zoonoses Committee in compiling this information is acknowledged.