A REVIEW OF BACTERIAL PATHOGENS FOUND IN RAW MILK AND THEIR HEALTH SIGNIFICANCE

Abstract

Raw milk has benefits such as maintenance of healthy bones due to the combination of nutrients helping prevent diseases such as osteoporosis, high protein content in milk making people full for a longer period of time thus reducing obesity, nutritional benefits due to the presence of nutrients, beneficial microflora and antibacterial systems and protection against the development of allergies. Milk is composed of water, fat, protein, lactose, enzymes, minerals and vitamins in different proportions. Milk is an excellent culture and protective medium thereby creating a conducive environment for pathogenic bacteria such as Salmonella, E. coli, Campylobacter spp, Staphylococcus aureus, Streptococcus spp and Listeria to thrive in. Thus, intake of raw milk has been associated with health complications such as typhoid fever, infantile gastroenteritis, campylobacteriosis, pneumonia, listeriosis and food poisoning. Pathogens contaminate milk through infested cattle faeces, udder, handler and utensil, mastitic milk and infertility as in the case of listeriosis. Thus, the objective of this paper was to review on bacteria pathogens associated with raw milk and their health significance. Salmonella has two species but only S. enterica is pathogenic and causes salmonellosis with nausea, vomiting, abdominal cramps, diarrhea, fever, chills, headache and blood in the stool as its symptoms. Pathogenic E. coli are of six types causing infertile gastroenteritis, hemolytic and uremic syndrome associated with symptoms of severe intestinal and extra intestinal diseases, diarrhea, abdominal cramp and vomiting. Streptococcus has S. pneumoniae, S. pyogenes and S. agalactiae as the pathogenic species causing pneumonia, sore throat and scarlet fever. Campylobacter has seven pathogenic species but only Campylobacter jejuni and Campylobacter coli are the most common pathogens causing campylobacteriosis. Staphylococcus aureus is the main bacteria responsible for causing foodborne poisoning in human due to its production of exotoxins. Listeria has L. monocytogenes and L. ivanovii as the pathogenic species responsible for septicemia, circling disease, encephalitis, abortion and still births. Proper handling of milk may alleviate health complications associated with pathogens contaminants. Practices such as pasteurization and sterilization of equipment are necessary to ensure milk safety.