The Raw Milk MOOvement:
A Public Health Perspective
Trisha Robinson, MPH
Epidemiologist
Foodborne, Vectorborne, and Zoonotic Diseases Unit
Minnesota Department of Health
www.boston.com
www.npr.org
Raw Milk
• Raw (unpasteurized)
milk has not been
heat treated
• Accounts for
approximately 1% of
milk sold in the
United States
Milk Contamination Opportunities
• Sick cow (may show no signs of illness)
• Contamination from the surface of the cow
as she is milked
• Environmental contamination
Pathogens in Bulk Tank Raw Milk
•
•
•
•
•
Campylobacter jejuni
E. coli O157
Listeria monocytogenes
Salmonella spp.
Yersinia enterocolitica
<1% - 12.3%
<1% - 3.8%
2.7% - 6.5%
<1% - 8.9%
1.2% - 6.1%
LeJeune et al, Clin Infect Dis 2009
A Serious Health Risk
• Some of the diseases that can be acquired
from raw milk include:
– Campylobacteriosis
– Salmonellosis
– Cryptosporidiosis
– E. coli O157
infection
– Brainerd Diarrhea
– Tuberculosis
– Brucellosis
– Listeriosis
– Yersiniosis
– Streptococcal
infections
– Staphylococcal
enterotoxin poisoning
Common Clinical Picture of Illness
• Acute gastroenteritis
– Fever, diarrhea (often bloody), abdominal
cramps, vomiting
• Complications
– HUS, Guillain-Barre Syndrome, death
• Vulnerable populations
– Children, elderly, immunocompromised
National Raw Milk Outbreaks
• Between 1973 and 1992, 46 raw milkassociated outbreaks were reported to CDC
from 21 states
– 57% Campylobacter spp.
– 26% Salmonella enterica
• From January 1998 to May 2005, 45
outbreaks implicated raw milk or cheese
made from raw milk
Raw Milk Outbreaks in Minnesota
Year
County
Pathogen
No. of
Cases
Setting
Consumer Description
1981
Scott
Campylobacter jejuni
25
Farm
School Field Trip
Attendees
1984
Crow Wing
Brainerd Diarrhea
122
Dairy
Community
1989
Polk
Campylobacter jejuni
8
Farm
School Field Trip
Attendees
1992
Itasca
Campylobacter jejuni
50
Church Picnic
Picnic Attendees
2000
Kittson
Campylobacter
8
Farm
Firefighter Trainees
2001
Otter Tail
Campylobacter jejuni
4
Farm
Ministry Group
2008
Pope
Campylobacter jejuni
2
Family Reunion
Reunion Attendees
2008
Crow Wing
Campylobacter jejuni
2
Dairy
Community
2010
Multiple
E. coli O157
8
Dairy
Community
Pasteurization
• Pasteurization is the process of heating milk
to a specific temperature for a defined length
of time, and then cooling it immediately
• Improves the safety and lengthens the shelf
life of milk by destroying pathogenic and
spoilage organisms
Temperature-Time Requirements for Milk
Temperature
Time
150° F
30 minutes
161° F
15 seconds
191° F
1 second
212° F
0.01 second
History of Pasteurization
• Pasteurization began in the U.S. in 1893
• Pasteurization had become the norm by the
end of the 1940s
Legal History of Raw Milk
• Interstate sale of unpasteurized dairy
products banned in 1987
• 29 states currently allow raw milk to be sold
in some capacity
Legal Sale of Raw Milk
Illegal
Goat milk only
Farms only
Farms & Retail
Raw Milk Regulations in Minnesota
• Minnesota allows raw milk to be
“occasionally secured or purchased for
personal use by any consumer at the place
or farm where the milk is produced”
• Farmer may not advertise the sale of raw
milk
• Retail sale of raw milk for human
consumption is illegal
Raw Milk Distribution
• Some people obtain raw milk without going
to the farm
– Drop off sites
– Buying clubs
• Alternative buying options gaining popularity
– Word of mouth
– Internet sites
– Facebook groups
Cow Share Programs
• Consumers buy a percentage of a cow’s milk
for a fee and then receive a certain amount of
raw milk per week
Opposition to Pasteurization
• Some advocates believe pasteurization:
– Removes naturally occurring enzymes,
vitamins, and minerals
– Is a government conspiracy
• Some advocates believe raw milk:
– Tastes better
– Enhances fertility
– Contains anti-viral agents
– Prevents and treats disease
Raw Milk Movement
• Demand for natural and unprocessed foods
• Concept of “produce, sell, and buy local”
• Freedom of choice
Truth in Pasteurization
• The validity of any
health or nutritional
benefit from
consuming raw milk
has never been
scientifically proven
• Pasteurization does
not change the
nutritional value of
milk
Position Statements on Dangers
Associated with Raw Milk Consumption
How Many People Drink Raw Milk?
• 2006 FoodNet Population Survey found 2.0%
of Minnesotans consumed raw milk in the
7 days before interview
MDH Routine Surveillance
• Interview confirmed cases of enteric illness
about illness history and exposure
information, including raw milk consumption
Sporadic Raw Milk Cases by Year,
Minnesota, 2001-2009
70
60
50
40
30
20
10
0
2001
2002
2003
2004
2005
2006
2007
2008
2009
Sporadic Raw Milk Cases by Pathogen
•
•
•
•
79% Campylobacter
9% Cryptosporidium
8% Salmonella
4% E. coli O157:H7
Raw Milk Consumers in Minnesota
• 62% male
• Median age 17 years (range, <1 to 92 years)
– Median age 7 years for E. coli O157 cases
• Report getting raw milk from a variety of
sources (home farm, family farm, work,
neighbor, unknown farm, drop off site)
Sporadic Raw Milk Cases by Month,
Minnesota, 2001-2009
80
70
60
50
40
30
20
10
0
Jan Feb Mar Apr May Jun
Jul Aug Sep Oct Nov Dec
Raw Milk Consumption on Farms
• 248 dairy producers in Pennsylvania
surveyed
– 105 (42%) consumed raw milk
– 170 (69%) aware of foodborne pathogens
in raw milk
– Those not aware of pathogen risk were 2x
more likely to consume raw milk
– Taste and convenience most commonly
cited reasons for consuming raw milk
Jayarao et al, J Dairy Sci 2006
Raw Milk Consumption on Farms
• In 2009, 23% of sporadic raw milk consumers
reported consuming milk from their own
dairy farm
– Median age of farm family consumers was
17 (range, 2-70 years) vs. 12 (range, 1-57
years) for non-farm family consumers
2006
2007
2008
2009
Consumed Raw Milk from Home Dairy Farm
Yes
No
Unknown
7
28
16
13
32
14
7
38
9
12
40
0
Total
51
59
54
52
MDH Raw Milk Intervention
• Follow-up phone call
• Discuss health risks
• Encourage home pasteurization or buying
pasteurized milk
MDH Intervention Efforts
• Education may not be the solution
– 89% were already aware of the risks
associated with raw milk when first
contacted
• However, a follow up study found:
– 71% of cases thought follow-up phone call
was helpful
– 80% no longer consumed raw milk
Could Testing Be an Alternative?
• Product testing cannot ensure safety
– Milk contamination occurs sporadically
– Contamination may not be evenly
distributed
– Small infectious dose
– Undetectable numbers of organisms may
proliferate after testing
RealRawMilkFacts.com
Questions?