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Unpaseurized Milk Articles
Bielaszewska, M., J. Janda, et al. (1997). "Human Escherichia coli O157:H7 infection associated with the consumption of unpasteurized goat's milk." Epidemiol Infect 119(3): 299-305.
A cluster of four cases of haemolytic uraemic syndrome in children occurred in Northern Bohemia, Czech Republic, between 15 June and 7 July, 1995. All the cases had significantly elevated titres of anti-O157 lipopolysaccharide (LPS) antibodies as detected by the indirect haemagglutination assay. All but one of them had drunk unpasteurized goat's milk from the same farm within the week before the disease. Evidence of E. coli O157 infection was subsequently found in 5 of 15 regular drinkers of the farm's raw goat's milk; four of them were asymptomatic, 1 had mild diarrhoea at the end of June. Verocytotoxin 2-producing E. coli O157:H7 strains of phage type 2 and of identical pulsed-field gel electrophoresis patterns were isolated from 1 of 2 farm goats and from 1 of the asymptomatic goat's milk drinkers. The frequency of anti-O157 LPS antibodies found among regular drinkers of the farm's raw goat's milk (33%; 5 of 15) was significantly higher than that found in control population (0%; none of 45) (P = 0.0005; Fisher's exact test). Our findings indicate that goats may be a reservoir of E. coli O157:H7 and a source of the infection for humans; raw goat's milk may serve as a vehicle of the pathogen transmission.
Blaser, M. J., J. Cravens, et al. (1979). "Campylobacter enteritis associated with unpasteurized milk." Am J Med 67(4): 715-8.
Campylobacter fetus ss. jejuni has recently been recognized as a human enteric pathogen. Laboratory isolation has been hindered by its fastidious nature. Methods for recovery of this organism from stool culture and a specific serologic test are described. An outbreak is reported in which three members of the same family became simultaneously ill with fever, severe abdominal cramps and diarrhea. C. fetus ss. jejuni was recovered from stool specimens from all three. A fourfold increase in serum immunoglobulin G (IgG) titer to this organism was demonstrated in each patient. All three patients had been consuming unpasteurized milk from a cow whose feces were infected with C. fetus ss. jejuni.
CDC (2002). "Outbreak of Campylobacter jejuni infections associated with drinking unpasteurized milk procured through a cow-leasing program--Wisconsin, 2001." MMWR Morb Mortal Wkly Rep 51(25): 548-9.
On December 7, 2001, the Sawyer County Department of Health and Human Services in northwestern Wisconsin notified the Wisconsin Division of Public Health about five cases of Campylobacter jejuni enteritis. All of the ill persons drank unpasteurized milk obtained at a local dairy farm. This report summarizes the investigation of these and other cases and of a cow-leasing program used to circumvent regulations prohibiting the sale of unpasteurized milk in Wisconsin. The outbreak highlights the hazards of consuming unpasteurized milk and milk products.
Chin, J. (1982). "Raw milk: a continuing vehicle for the transmission of infectious disease agents in the United States." J Infect Dis 146(3): 440-1.
Doyle, M. P. and D. J. Roman (1982). "Prevalence and survival of Campylobacter jejuni in unpasteurized milk." Appl Environ Microbiol 44(5): 1154-8.
Campylobacter jejuni was isolated from 1 to 108 (0.9%) milk samples obtained from the bulk tanks of nine grade A dairy farms and from 50 of 78 (64%) cows producing grade A milk. Survival of eight Campylobacter strains in unpasteurized milk (4 degrees C) varied greatly: the most tolerant strain showed a less than 2-log10 decrease in viable cells after 14 days, and the most sensitive strain showed a greater than 6-log10 decrease after 7 days. One strain was still recoverable 21 days after the inoculation of milk. Inactivation of the different strains corresponded with an increase in milk aerobic plate count and a decrease in milk pH; however, no absolute correlation could be made between the rates of change of these parameters and the rates of campylobacter inactivation. When held at 4 degrees C, C. jejuni was most stable in brucella broth, died most rapidly in unpasteurized milk, and was inactivated at an intermediate rate in sterile milk. Our results indicate the presence and possible persistence of C. jejuni in raw grade A milk and reaffirm the need for pasteurization of milk.
Headrick, M. L., S. Korangy, et al. (1998). "The epidemiology of raw milk-associated foodborne disease outbreaks reported in the United States, 1973 through 1992." Am J Public Health 88(8): 1219-21.
OBJECTIVES: This study describes the epidemiology of raw milk-associated outbreaks reported to the Centers for Disease Control and Prevention from 1973 through 1992. METHODS: Surveillance data for each reported raw milk-associated outbreak were reviewed. A national survey was conducted to determine the legal status of intrastate raw milk sales for the period 1973 through 1995. RESULTS: Forty-six raw milk-associated outbreaks were reported during the study period; 40 outbreaks (87%) occurred in states where the intrastate sale of raw milk was legal. CONCLUSIONS: Consumption of raw milk remains a preventable cause of foodborne disease outbreaks.
Keene, W. E., K. Hedberg, et al. (1997). "A prolonged outbreak of Escherichia coli O157:H7 infections caused by commercially distributed raw milk." J Infect Dis 176(3): 815-8.
A protracted outbreak of Escherichia coli O157:H7 infections was caused by consumption of unpasteurized ("raw") milk sold at Oregon grocery stores. Although it never caused a noticeable increase in reported infections, the outbreak was recognized because of routine follow-up interviews. Six of 16 Portland-area cases reported between December 1992 and April 1993 involved people who drank raw milk from dairy A. By pulsed-field gel electrophoresis (PFGE), E. coli O157:H7 isolates from these cases and from the dairy A herd were homologous (initially, 4 of 132 animals were E. coli O157:H7-positive). Despite public warnings, new labeling requirements, and increased monitoring of dairy A, retail sales and dairy-associated infections continued until June 1994 (a total of 14 primary cases). Seven distinguishable PFGE patterns in 3 homology groups were identified among patient and dairy herd E. coli O157:H7 isolates. Without restrictions on distribution, E. coli O157:H7 outbreaks caused by raw milk consumption can continue indefinitely, with infections occurring intermittently and unpredictably.
Potter, M. E. (1985). Statement of Morry Potter, DVM. Hearings before the Subcommittee on Health and the Environment of the Committee on Energy and Commerce House of Representatitves, Washington D.C., U.S. Government Printing Office.
Potter, M. E., M. J. Blaser, et al. (1983). "Human Campylobacter infection associated with certified raw milk." Am J Epidemiol 117(4): 475-83.
Between May 27 and June 18, 1981, 50 individuals in 30 households in suburban Atlanta, Georgia, had a gastrointestinal illness caused by Campylobacter jejuni. Epidemiologic evidence strongly associated consumption of unpasteurized milk with illness. A culture survey confirmed fecal carriage of C. jejuni by cows in the implicated dairy and in a control dairy, but failed to document presence of the organism in the milk. The standard plate counts and leukocyte counts (two indicators of microbiologic quality of milk), facilities, and operating procedures at the implicated dairy were all within accepted levels for production of Grade A raw milk in Georgia. Inasmuch as the parameters used by regulatory officials to determine the wholesomeness of milk were not violated at the implicated dairy, the only means available to ensure the public's health would be proper pasteurization before consumption.
Potter, M. E., A. F. Kaufmann, et al. (1984). "Unpasteurized milk. The hazards of a health fetish." JAMA 252(15): 2048-52.
Meaningful differences in nutritional value between pasteurized and unpasteurized milk have not been demonstrated, and other purported benefits of raw milk consumption have not been substantiated. Conversely, the role of unpasteurized dairy products in the transmission of infectious diseases has been established repeatedly. To effectively counsel patients attracted by the health claims made for raw milk, practicing physicians must understand both the rationale used by proponents of raw milk and the magnitude of the risk involved in drinking raw milk.
Sharp, J. C., G. M. Paterson, et al. (1985). "Pasteurisation and the control of milkborne infection in Britain." Br Med J (Clin Res Ed) 291(6493): 463-4.
Infections carried in milk, particularly salmonellosis and campylobacter enteritis, have continued to feature in Great Britain in recent years. Less commonly reported infections included an outbreak in 1984 in England due to Streptococcus zooepidemicus, in which 12 people, eight of whom died, were admitted to hospital. The implementation of legislation in 1983 requiring heat treatment of cows' milk for sale to the public reduced the incidence of milkborne infection in Scotland compared with previous years and compared with England and Wales, where, without legislative control, outbreaks continue to occur. Until compulsory pasteurisation is introduced throughout Britain and dairy farming communities can be persuaded to drink only heat treated milk outbreaks of milkborne infection will continue.
Taylor, D. N., J. M. Bied, et al. (1982). "Salmonella dublin infections in the United States, 1979-1980." J Infect Dis 146(3): 322-7.
Human isolates of Salmonella dublin were reported to the Centers for Disease Control, Atlanta, 103 times in 1980, as isolation rate nearly twice that reported in 1979. In 1979 and 1980 S. dublin was isolated predominantly in the western United States, frequently from males (60% of the total), from adults older than 40 years of age (55%), and from blood (37%). Detailed histories were obtained for 39 cases outside of California and Oregon, and 32 cases were matched with 62 age-, sex-, and locality-matched control subjects. We found that persons infected with S. dublin were more likely to have suffered from chronic noninfectious diseases (P less than 0.001) and were more likely to have ingested antacids (P less than 0.01) than their controls. In the case-control study, 21 (66%) of the infected persons were hospitalized and six (19%) died. When exposure to cattle, beef, or dairy products was examined, we found that cases differed significantly from controls only by a more frequent consumption of raw milk (P less than 0.001).
Taylor, D. N., B. W. Porter, et al. (1982). "Campylobacter enteritis: a large outbreak traced to commercial raw milk." West J Med 137(5): 365-9.
Taylor, J. P. and J. N. Perdue (1989). "The changing epidemiology of human brucellosis in Texas, 1977-1986." Am J Epidemiol 130(1): 160-5.
From 1977-1986, a total of 331 laboratory confirmed cases of human brucellosis were reported in Texas. The annual number of cases ranged from 13 in 1977 to 84 in 1983. Males accounted for 66% of the cases. Cases ranged in age from one to 92 years, with 57% between the ages of 20 and 49 years. Brucella melitensis infections accounted for 66% of the bacteriologically confirmed cases. Infection with Brucella canis was identified in four patients. Annual incidence rates were higher in Hispanics in each age and sex group when compared with whites and blacks. Epidemiologic features of cases reported during 1977-1981 are dissimilar to features of cases reported during 1982-1986. In the first five years, a majority of cases (82%) were males, and a majority (54%) were white. Exposure to cattle or swine was reported for 72% of the cases. In the second five years, a majority (72%) of cases were Hispanic, and only 55% were males. Ingestion of unpasteurized goat milk products was reported for 67% of the cases during 1982-1986
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