1. Based on the graph, make an inference about where the "community acquired" penicillin resistant S. aureus originated from.

The "community acquired" penicillin resistant S. aureus originated from the hospital since 1940’s based on the graph and after 10 years, S. aureus resistant increases to 60%. In 1960’s, it spread to the community and eventually spread across the world.

Moreover, Staphylococcus aureus infections can be treated with penicillin in the past but when it became resistant to penicillin, pharmaceutical companies discovered methicillin, which is a derivative of penicillin. However, S. aureus resistant was also develop with methicillin from late 1980’s in the hospital and in the community from the start of year 2000.