Regulation of Raw Milk Cheeses in Other Countries

Canada regulates cheeses made from raw milk similar to the US, except for Quebec where raw milk cheeses can be manufactured without 60-day aging if strict rules for milk quality and veterinary inspections of cattle herds are followed.  In 1996, following an outbreak of E. coli O157:H7 linked to cured Gouda cheese, Health Canada proposed a ban on all raw milk cheeses, but the initiative was defeated by industry and consumer groups (Honish 2005).

The European Union has no aging rule, but their requirements for hygiene during milking, storing, and collection of milk for cheesemaking are likely much stricter than in the US.  Additionally, requirements for both animal health and worker/personnel health help ensure safe raw milk cheese production.  Cheeses made from raw milk in Europe must be labeled “Made with Raw Milk.”

The regulation of raw milk cheeses in Australia and New Zealand has been an area of intense controversy in recent years.  Australia bans all domestic raw milk cheeses, but allows importation of certain cheeses—Roquefort, Gruyere, Sbrinz, Emmental—from Europe and Switzerland provided they are aged 90 days and meeting European safety standards (Standard 4.2.4A).  Domestic cheeses must be “thermised” by using a low temperature heat treatment followed by aging for 90-days.


The epidemiology of cheese-related outbreaks has changed in the US since the 60-day aging rule was established in 1950.  The studies conducted in the 1940’s that presumably  provided the basis for the rule were based on diseases such as Typoid fever, an infection transmitted by human carriers.  Today, most of the cheese-linked illnesses are due to zoonotic enteric pathogens carried by ruminants including Campylobacter, E. coli O157:H7, Listeria monocytogenes, and SalmonellaL. monocytogenes is also a ubiquitous inhabitant of the dairy environment.  Table 2 shows some of the major pathogens that may survive in cheese even after aging.  

Internationally, dairy-related outbreaks are relatively uncommon in developed countries, but an estimated 11.8% are attributed to cheeses made from raw milk (FSANZ 2006).  Foodborne disease outbreaks have been reported in all countries that allow raw milk cheese including France where raw milk cheeses are popular (Desenclos 1996; Desenclos 1996; DeValk 2000; Dominguez 2009; Haeghebaert 2003; Ostyn 2010).  The most recent published review in the US examined reported cheese-related outbreaks and illnesses from 1973 – 1992 (Altekruse 1998).  Fresh Mexican-style cheeses (for example, queso fresco) were the most frequently implicated vehicle and caused 56 of the 58 deaths described in the review; the other 2 deaths were linked to improper pasteurization of Mozzarella cheese. 

Table 2.  Bacterial pathogens that can survive in cheeses aged for 60 days.



Duration of illness

Signs and symptoms


Brucella spp.

1-2 months or longer

May relapse for years

Fever, headache, joint pain, depression, weight loss

Cause of abortions in dairy animals


2-5 days

2-7 days; some patients develop paralytic syndrome as a long-term complication

Diarrhea (sometimes bloody), cramps, fever, nausea, vomiting, muscle aches

Found in health dairy animals

E. coli O157 and other pathogenic E. coli

2-8 days

5-8 days; some patients develop kidney disease or other long-term complications

Diarrhea (often bloody), cramps, sometimes low-grade fever

Found in healthy dairy animals

Listeria monocytogenes

3 – 70 days (average 3 weeks)

Variable depending on susceptibility; Death rate in patients with meningitis as high as 80%; septicemia as high as 50%

Septicemia, meningitis, intra-uterine infections in pregnant women with spontaneous abortions and stillbirths

Found in healthy dairy animals and the dairy processing environment

Mycobacterium bovis

4 – 12 weeks to positive tuberculin test; 1-2 years for systemic infection

Years; may persist lifetime as latent infection

Pulmonary and extra-pulmonary disease

Systemic illness in cattle; transmitted through milk and aerosols

Salmonella enterica

6 – 48 hours

 2-8 days; some patients develop long-term complications including arthritic disease

Diarrhea, nausea, vomiting, cramps fever

Some strains cause illness in dairy animals

Salmonella typhi

8 – 14 days

Variable;  case fatality of 10-20% without antibiotic treatment

Fever, cramps, diarrhea, anorexia

Human carriers

Staphylococcus enterotoxin

2-4 hours

1-3 days

Vomiting, nausea, cramping

Animal and human carriers; toxin produced following growth in a food

The problem with fresh, soft cheeses is ongoing and most often associated with use of inadequately pasteurized milk and cross-contamination in the processing environment (CDC 2000; CDC 2001; CDC 2008; CDC 2009; Cody 1999; MacDonald 2005; Villar 1999).  Listeria monocytogenes and Salmonella are pathogens most often found in fresh Mexican-style soft cheeses as reviewed previously (Marler, 2009).  Over the last decade, there have been only two deaths from cheese made with raw milk; both occurred in 2003, and were due to consumption of contaminated fresh (un-aged) queso fresco Mexican-style cheese (CDC OutbreakNet).

In contrast, outbreaks and illnesses linked to 60-day aged cheese are relatively rare despite microbiological evidence of pathogen survival in these cheeses (Altekruse 1998; D’Amico 2008b; D’Amico 2010; Donnelly 1990; Jaros 2008; Reitsma 12996; Schlesser 2006).  Researchers from the University of Vermont have speculated that the relative paucity of outbreaks and illnesses associated with 60-day aged cheese may be due to 1) a low contamination level in milk used for cheesemaking or 2) alterations in virulence of pathogens within the cheese matrix (D’Amico 2010).

However, there are notable exceptions including E. coli O157:H7 outbreaks linked to cured Gouda cheese in Canada in 2002 (Honish 2005) and the US in 2010 (CDC 2010).  In the latter, at least 38 cases have been linked to consumption of Gouda cheese made with raw milk and presumably aged for 60-days in accordance with FDA regulations.  The CDC summarized findings from the ongoing investigation in a November 24, 2010 report:


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