MRSA (Methicillin-resistant Staphylococcus aureus)

Our MRSA (Methicillin-resistant Staphylococcus aureus) design draws attention to the increasingly serious issue of antibiotic resistance. Typically transmitted skin-to-skin, MRSA in its earliest form was primarily a hospital-acquired pathogen. However, it has now mutated into a community-acquired strain, characterized by excretion of a potent toxin which attacks the immune system and destroys tissues. It is important to note that resistant forms look the same as other bacteria except that they bear genes and products  as demonstrated in our design by the glow around the mutant strains - which protect them from antibiotics.

Inspiration for this design was provided by APUA (Alliance for the Prudent Use of Antibiotics), an international organization dedicated to improving use of antimicrobials use and curbing antimicrobial resistance world wide. (


Magnified 20,000X, this colorized scanning electron micrograph (SEM) depicts a grouping of methicillin resistant Staphylococcus aureus (MRSA) bacteria. See PHIL 617 for a black and white view of this image.

These S. aureus bacteria are methicillin-resistant, and are from one of the first isolates in the U.S. that showed increased resistance to vancomycin as well. Note the increase in cell wall material seen as clumps on the organisms surface.

This 2005 scanning electron micrograph (SEM) depicted numerous clumps of methicillin-resistant Staphylococcus aureus bacteria, commonly referred to by the acronym, MRSA; Magnified 9560x.

Recently recognized outbreaks, or clusters of MRSA in community settings have been associated with strains that have some unique microbiologic and genetic properties, compared with the traditional hospital-based MRSA strains, which suggests some biologic properties, e.g., virulence factors like toxins, may allow the community strains to spread more easily, or cause more skin disease. A common strain named USA300-0114 has caused many such outbreaks in the United States.

Methicillin-resistant Staphylococcus aureus infections, e.g., bloodstream, pneumonia, bone infections, occur most frequently among persons in hospitals and healthcare facilities, including nursing homes, and dialysis centers. Those who acquire a MRSA infection usually have a weakened immune system, however, the manifestation of MRSA infections that are acquired by otherwise healthy individuals, who have not been recently hospitalized, or had a medical procedure such as dialysis, or surgery, first began to emerged in the mid- to late-1990's. These infections in the community are usually manifested as minor skin infections such as pimples and boils. Transmission of MRSA has been reported most frequently in certain populations, e.g., children, sports participants, or jail inmates.

What you need to know about the critical issue of antibiotic resistance and its prevention.