Staphylococcus Aureus Is a Type

Staphylococcus aureus is a type of bacteria that normally resides in or on humans. It is most often diagnosed by obtaining a culture from the areas suspected of infection. The proper method to identify S. aureus is through clinical isolation (Sewell, 2002, p. 1077), using such methods as microscope, colony morphology, and other tests (Rowlinson et al., 2006, 857). One method of growing S. aureus in laboratory, as demonstrated in an experiment, is by using Difco Antibiotic medium III at 37° C. with shaking (Koch et al., 1984, p. 358).

What is most important for the growth of the bacteria is the level of temperature which has been demonstrated to interfere with the process (Joyce et al., 1970, p. 323). But what raises concerns nowadays is resistance to antimicrobial agents which can lead to various infections. In this respect, antibiotic resistance can be depicted by PCR and DNA sequencing. Based on their conducted study, Duran et al. (2012), concluded that "the detection of mecA gene by PCR techniques is considered the gold standard method." (p.

394) Because we live in a world surrounded of bacteria, the majority of them undetectable at once, antibiotic resistance poses a great challenge as man is more and more subjected to catching bacteria that are difficult to treat. When the bacteria resides on an individual but is unthreatening, it is said that person is colonized. Colonization can be of various durations, sometimes transient or may establish itself for a period of years in which case it is named persistent (Sanford et al., apud Chambers, 2001, p. 178).

Children are more susceptible to catching the bacteria through respiratory tracts, but generally, over 25% to 33% of individuals carry it. The bacteria can also come from poor sanitation, which ultimately can lead to food poisoning. Tests are therefore conducted to examine if there is a presence of S. aureus that caused the illness and if the bacteria is or can be recognised as a potential source for food poisoning (Bennet & Lancette, 2001).

One such test is known under the name of Direct Plate Count Method as it was illustrated by Bennet and Lancette, generally requiring a step-by-step procedure involving a. Equipment and materials, B. Media and reagents, C. Preparation of sample, D. Isolation and enumeration of S. aureus, E. coagulase test, F. Ancillary tests, and G. Knowledge of some typical characteristics of species of staphylococci and micrococci (Bennet & Lancette, 2001).

After considering several mediums for growing Staphylococcus, it seems Tryptic Soy Agar (TSA) is of some convenience as it allows for the cultivation of a wide variety of microorganisms. Also, the nutritional composition favours plate counting which is beneficial in the examination of.