States today, milkborne cases of tuberculosis are relatively uncommon, but it is a
serious problem in some areas where adequate control measures are not in effect.
(2) Brucellosis. This disease is caused by a group of organisms known as
Brucella. The disease is called undulant fever in man. In cattle, it is often called Bang's
disease or contagious abortion. It is usually spread by contact with infected animal
materials or by consumption of raw milk from diseased animals. As with tuberculosis,
programs for eradication are in effect to eliminate brucellosis in dairy herds.
(3) Q fever. This disease is a pneumonia-like disease caused by a rickettsial
organism, Coxiella burnettii. It is commonly disseminated by airborne organisms, by
contact with infected animals, or by consumption of raw milk from infected cows. The
heat resistance of this organism is reflected in the need to use a time-temperature
combination of 145F (63C) for 30 minutes or equivalent high temperature short time
pasteurization temperatures.
(4) Mastitis. Mastitis is an infection of the cow's udder. It may be caused by
mechanical injury or by several species of the Streptococcus and Micrococcus
organisms. Some species of these groups are pathogenic and are a potential source of
disease to the consumer.
(5) Salmonellosis. There are a number of diseases caused by the genus
Salmonella, which contains a wide variety of "species" pathogenic for both man and
animals. They may be transmitted from animal to man. Three clinically distinguishable
forms of salmonellosis occur in man: enteric fevers, septicemias, and acute
gastroenteritis.
b. Man to Man. The contamination of milk, milk products, or milk-handling
equipment by persons recovering from an infectious disease, or acting as a carrier of a
disease, is perhaps the most common cause of milkborne disease. Typhoid and
paratyphoid fever, scarlet fever, septic sore throat, diphtheria, cholera, amebic
dysentery, and infection by organisms of the Salmonella genus may be transmitted in
this manner.
1-7. CONTROL OF MILKBORNE DISEASES
a. Healthy Cows. Milk for dairy product production should be extracted from
healthy cows only. Dairy herds are tested and inspected by state and/or federal
veterinarians.
b. Healthy Employees. Dairy farm milk handlers and dairy plant personnel
must pass periodic medical examinations. Employees must be free of communicable
disease, open sores, and cuts. Good personal hygiene must be practiced at the farm,
milking parlor, collection vehicles and stations, dairies, and retail outlets.
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