What is raw milk and why is it a concern?
Raw milk is milk that has not been pasteurized.   Drinking unpasteurized milk or raw milk products can result in a variety of mild to severe illnesses, including death.   It can affect not only those who choose to consume it, but also those who do not.

 

It is illegal for anyone in Canada to distribute or sell raw milk and raw milk products. 
 
Why is milk pasteurized?
The pasteurization of milk was implemented specifically to destroy common pathogens found in raw milk and, secondarily, to give milk a longer shelf life by reducing the number of spoilage-causing organisms.  Even under the strictest conditions, cows naturally carry certain disease-causing bacteria which may be passed to the milk that they produce, including Salmonella, Campylobacter, Listeria, Tuberculosis and E.coli 0157:H7.   The bacteria do not harm the cow, but humans consuming unpasteurized milk may become infected, leading to serious health concerns such as meningitis, encephalitis, septicemia, endocarditis, spontaneous abortion and tissue abscesses.    Common symptoms of an infection include severe diarrhea (which may be bloody), stomach cramps or abdominal pain, vomiting, fever, weakness and chills.   Certain groups, such as the young, elderly, ill, pregnant women or those with compromised immune systems, are at increased risk. 

 

How does pasteurization make milk safe to drink?
Pasteurization is the process of heating milk for the purpose of destroying disease-producing organisms that cause bacteria-related illnesses.  The minimal pasteurization requirement in Ontario is to heat the milk to 72° Celsius for 16 seconds at a dairy processing plant to destroy disease-producing bacteria.

 

Can raw milk be sold?
All milk sold in Canada for human consumption must be pasteurized.  Milk-related legislation is complex and many agencies are involved.  Since 1938, strict legislation has made it mandatory for all Ontario dairy farmers to sell or distribute only pasteurized milk.  Under the Health Protection and Promotion Act (HPPA), the sale, delivery and distribution of unpasteurized milk and milk products in Ontario is prohibited.  Health Units are responsible for enforcing this Act.  Under the legislation, a Medical Officer of Health, or their designate, can seize milk products and issue a “cease and desist” order to stop the sale or distribution of milk products.

 

There are some exceptions to the prohibition of the sale of unpasteurized milk and milk products.  Certain raw milk cheeses are permitted to be sold because harmful bacteria are destroyed during manufacture and aging.  These cheeses must be made according to Health Canada guidelines.  Ontario farmers are allowed to drink raw milk produced by their own goats or cows.  Unpasteurized milk distribution is also allowed under regulated conditions in other jurisdictions, including some parts of the United States and Europe.  Continued raw milk-related outbreaks in these areas, however, are increasing the call for pasteurization legislation.  

 

Have there been recent cases of raw-milk related illness?
The true incidence of food and milk-borne diseases is unknown because people may not relate illness to consuming raw milk, or may not report illness to their physician.  Recent outbreaks in Ontario from unpasteurized milk consumption include one that occurred in Barrie in April 2005.  At least four people became ill with E.coli 0157:H7 disease, the same bacteria that caused the outbreak in Walkerton, Ontario, though there may have been additional, unreported cases. 

 

According to the Ministry of Health and Long-Term Care, between 2005 and 2007, 92 cases of illness caused by unpasteurized milk or cheese made from unpasteurized milk were reported in Ontario. With 61 cases reported, Campylobacteriosis was the most common illness caused by unpasteurized milk or cheese made from unpasteurized milk.

 

Can the bacteria from drinking unpasteurized milk be passed on to others?
If someone becomes ill from drinking raw milk, the infection can be passed from person to person by hand-to-mouth contact.  Individuals can also become asymptomatic carriers of disease, passing the disease on to another without showing signs of illness themselves.

 

Is raw milk more nutritious than pasteurized milk?
Pasteurization destroys disease-causing pathogens while having little effect on the quality of milk and the loss of nutrients.  It does not effect the quality of nutrients present in fluid milk, such as calcium, protein, riboflavin, niacin, folic acid, vitamin B6, pantothenic acid and vitamin A.  About 20 per cent of vitamin C is destroyed during pasteurization; however, milk is not a significant source of vitamin C.  Any other loss of nutrients is less than 10 per cent.  Vitamin D, which improves the absorption of calcium, is added to pasteurized milk.  Raw milk does not contain a significant amount of vitamin D.

 

What should I do if I drink raw milk and develop symptoms of an infection?
Anyone who shows symptoms should see their doctor immediately.  Symptoms include severe diarrhea (which may be bloody), stomach cramps or abdominal pain, vomiting, fever, weakness and chills.   About 10 per cent of people with E.coli 0157:H7 develop Hemolytic Uremic Syndrome (HUS).  HUS is a serious complication that can lead to kidney failure and death.

 

Ontario Ministry of Health and Long-Term Care Fact Sheet
http://www.health.gov.on.ca/english/public/pub/pub_menus/pub_foodsafe.html
 
Ontario Ministry of Agriculture, Food and Rural Affairs Fact Sheet
http://www.omafra.gov.on.ca/english/food/inspection/dairy/pasteurized%20milk%20infosheet.htm

 

Health Canada’s Position on Raw Milk
http://www.hc-sc.gc.ca/ahc-asc/media/advisories-avis/_2006/2006_65-eng.php

 

Dairy Farmers of Ontario – Pasteurization
http://www.milk.org/corporate/view.aspx?content=Faq/Pasteurization

 

Centers for Disease Control and Prevention 
http://www.cdc.gov/mmwr/preview/mmwrhtml/00000104.htm
http://www.cdc.gov/mmwr/preview/mmwrhtml/00000318.htm
http://www.cdc.gov/enterics/publications/425-Jain2007.pdf
http://wonder.cdc.gov/wonder/prevguid/p0000005/p0000005.asp