Drinking unpasteurised milk is risky

With the dairy season in full swing the New Zealand Food Safety Authority is highlighting the dangers of drinking unpasteurised or raw milk.

NZFSA’s principal adviser for public health Dr Donald Campbell says drinking unpasteurised milk is risky because it hasn’t been heat treated to kill any harmful bacteria that might be in the raw product, such as Salmonella, E. coli, Campylobacter and Listeria monocytogenes.

“Everyone can get sick from drinking milk contaminated with these bugs, especially if it is not properly refrigerated as this provides the perfect conditions for them to grow. However, more vulnerable groups such as babies and toddlers, the frail elderly, expectant mothers and people with weakened immune systems, are at greater risk of getting sick and the consequences for them can be more severe.”

The general retail sale of raw drinking milk is not permitted in New Zealand, though under the Food Act 1981 people are allowed to purchase up to five litres from the farm gate if they intend to drink it themselves or provide it to their family. It is important to note that such milk must have been harvested in accordance with an approved Risk Management Programme (which is appropriate for milk for direct human consumption) under the Animal Products Act 1999.

Outbreaks of foodborne disease such as salmonellosis, campylobacteriosis and E. coli infection have been attributed to drinking raw milk.

While illness caused by harmful bacteria in raw milk can be a mild bout of vomiting or diarrhoea, people sometimes develop symptoms that are chronic, severe or even life-threatening. Dr Campbell emphasises that the only completely safe way to avoid getting food poisoning from raw milk is not to drink it and opt for pasteurised milk instead.

Background:

It is very easy for harmful bacteria to get into raw milk during the milking process. They can cross into milk while it is still in the udder (via unrecognised mastitis) or milk can be contaminated from the dairy farm environment during milking. Once contaminated, raw milk is not subjected to any step between collection and consumption that will rid milk of the harmful bacteria; unlike pasteurised milk, which receives a heat treatment that kills them. In addition, bacteria may grow if the raw milk is stored improperly, and even if stored at refrigeration temperatures, some, like Listeria monocytogenes, are still able to grow.

Ends

For further comment contact: Dr Donald Campbell, Principal Advisor (Public Health), 04 894 2649 or 029 894 2649

For further information contact: Miriam Meister, Adviser (Media Communications), 04 894 2466 or 029 894 2466.