Identification of Potentially Pathogenic Yeast Species in Seagull Guano by Molecular Techniques

Although studies have been performed identifying bacteria present in seagull guano, limited studies have been done with fungi, leaving a significant gap in our knowledge of a potentially significant reservoir of human disease. If pathogenic fungi are being deposited by seagulls in their feces then it is possible that the Department of Health might elect to monitor sand, as well as water, for a broad spectrum of disease-causing microbes. Currently only water is tested for the presence of coliform bacteria. It is hypothesized that there are pathogenic yeastlike fungi present in the guano of seagulls, that these fungi are deposited in areas around Myrtle Beach. These fungi may present a potential health risk to beach-goers. Six samples were collected from solid surfaces at randomly chosen public beach accesses within the Myrtle Beach city limits. These samples were then washed, diluted, and plated on Bengal Rose agar, which enhances fungal growth, and incubated at 37 degrees Celsius. Discrete colonies were then selected and grown in Sabouraud Dextrose broth at 37 degrees Celsius. Following this step DNA was isolated from the fungal cultures and polymerase chain reaction was performed, using universal fungal primers to amplify the ITS-5.82S-ITS2 region of the rDNA, which yielded three PCR products for sequencing. The sequencing reactions were unsuccessful but it was apparent that seagull guano acts as a carrier for fungi whose presence could impact the health of beachgoers. The relative significance of this source, as well as the other potential sources, may lend suggestions for controlling the presence of potentially pathogenic fungi on recreational beaches to public health officials.