by George Looby, DVM
Two of the major diseases that prompted the industry and public health officials to develop standards for the sale of milk many years ago are still with us. Brucellosis and tuberculosis have yet to be completely eradicated from this country, although they are found at increasingly lower levels. Pasteurization has played the major role in this control program but despite this, there remain a group of consumers who prefer to drink raw milk.
Recently a New Jersey company called Udder Milk was issued a cease and desist order by the New Jersey Department of Health after a woman who drank milk purchased from that company became infected with brucellosis. Of particular concern is that the strain isolated from the patient was Brucella RB51, a rare antibiotic resistant strain. As most are aware, Brucella abortus is the organism that causes contagious abortion in cattle and undulant fever in humans. It is a particularly nasty illness because those affected are prone to relapses that are quite debilitating.
The Brucella RB51 strain is the one that is used to vaccinate heifer calves between the ages of four and eight months against brucellosis. This vaccine, in use for many decades, has proven to be most effective in protecting these animals against the disease. If the vaccine is administered at an age older than recommended there is a chance that the organism will persist in the system and will give rise to a low-grade titer that can persist into adulthood rendering the cow a carrier. The criteria for vaccination may vary from state to state making it important that those involved be familiar with the regulations in the state in which they are working.
In Washington State there were two recorded cases of a rare strain of Salmonella which resulted in the hospitalization of both affected patients. The Washington State Department of Health was able to confirm that the strain of Salmonella Dublin, isolated from the hospitalized patients, matched that of those isolated from milk samples taken from the Pride and Joy processing plant located in Toppenish, WA. The samples taken from the plant were part of the routine testing program in place for all licensed raw milk dairy operations. Isolates from those samples were submitted to the State Department of Health where a linkage was established to the human cases found earlier in the year.
At the time when the two patients were diagnosed state inspectors did visit the plant and the samples collected at that time were negative for Salmonella but were positive for E. coli. This finding resulted in state inspectors working with management and plant personnel to correct existing sanitary deficiencies. At that time, some recently shipped milk was recalled from retail outlets and sales were temporarily discontinued during the cleanup process. At the same time state officials reminded the public that although raw milk can be sold at farm stands, drop off sites and retail stores throughout the state, it is considered a health hazard and is not recommended for young children, the elderly, pregnant women or people with compromised immune systems.
In Texas, the K-Bar Dairy, another raw milk distributor, has found itself in a similar situation where milk samples from its plant also tested positive for Brucella RB51. Again, a woman became ill after drinking milk from this facility. In this case, the milk produced was sold only at the dairy but the exposure to its products were far reaching — consumers from several states reported purchasing milk there. The source of the infection in this case was in the dairy herd where two cows were found to have been infected with the RB51 strain.
Education may seem repetitious, but ensuring everyone knows the potential risks is beneficial to all.
Raw milk still an issue
by George Looby, DVM