Ogston provided a sophisticated account of staphylococcal illness and its connection to sepsis and abscess formation in a series of clinical observations and laboratory investigations that were published in 1880 and 1882. Even after almost a century has passed, Staphylococcus aureus (S. aureus) is still a hazardous and adaptable bacterium for humans. While overall mortality has not changed, the frequency of staphylococcal infections acquired in hospitals and the community has both been rising substantially. Resistance toward every prominent class of antistaphylococcal antimicrobial drugs including glycopeptides, penicillins, tetracyclines, sulfonamides, and other therapies is displayed by S. aureus throughout its treatment history. While the number of complex S. aureus infections is increasing, there are novel antimicrobial drugs that can be used to treat the infection, such as linezolid and daptomycin. However, the treatment requires accurate identification of enterotoxin-secreting Staphylococcus aureus. The following chapter elaborates on the immunosensing strategy for the detection of S. aureus.