Prevalence of Staphylococcus aureus in Raw Milk and Some Dairy Products in Port Said Governorate

Staphylococcus aureus Food Poisoning is a common cause of food-borne disease worldwide. Of particular relevance is the ability of some Staphylococcus aureus strains to produce heat stable enterotoxins that cause staphylococcal food poisoning, which ranks as one of the most prevalent worldwide causes of gastroenteritis. Several studies have shown that 15% to 80% of the Staphylococcus aureus isolated from various sources (dairy products, ice heavy cream, meat products) is able to produce enterotoxin. Classically, enterotoxins from Staphylococcus aureus strains can be classified into 18 serological types: A-U (except S, F and T), most of these serotypes are heat stable. The percentage of samples of milk and milk products contaminated with S. aurues in the current study were 46% which is higher than that reported by who detected S. aureus in 17 % and 32 % respectively of the analyzed samples of milk and milk products. Staphylococcal enterotoxins are low molecular weight proteins (MW 26.900 – 29,600).They are encoded by genes embedded in mobile genetic elements such as phages and pathogenicity islands .There are several methods for detection of enterotoxigeneic bacteria. The phonotypical methods are not reliable in specificity, because staphylococcal enterotoxins serotypes are antigenically similar. On the other hand, commercial serological kits can not detect all the serotypes and are limited in serotypes (A-B). Therefore, molecular techniques such as multiplex polymerase chain reaction and real-time polymerase chain reaction are recommended for detection of Staphylococcus aureus enterotoxins genes