As part of a Master's Thesis, samples of sand and water were taken at three beaches along Tampa Bay and analyzed for bacterial concentration and antibiotic-resistant bacteria. The sites were Courtney Campbell beach, Ben T. Davis Beach, and Cypress Point Park Beach (Figure 1).

At each beach, one liter samples of water were collected, along with two sand samples - one in the 'swash' zone, where the incoming waves interact and mix with the sand, as well as the 'foreshore', where the waves do not reach.

The samples were filtered for total E. coli and enterococci, as well as ampicillin-resistant E. coli and erythromycin-resistant enterococci. Antibiotic-resistant bacteria were confirmed to species or genus level and then tested for multidrug resistance using the Kirby-Bauer assay. Ampicillin-resistant E. coli isolates were tested against six additional antibiotics, while erythromycin-resistant Enterococcus spp. isolates were tested against five additional antibiotics (Figure 2 A and B, respectively).