Abstract
Between 25–30% of humans are colonized by Staphylococcus aureus and approximately 2% are methicillin-resistant (MRSA) or resistant to other beta-lactam antibiotics.5 These bacteria represent a potential public health threat and understanding the biology and transmission of disease is important.10 Animals can be infected with MRSA organisms and concern is on the rise as production animals and pets may be sources of human infections.6 Dolphins, both free-ranging and managed populations, have been diagnosed with Staphylococcus aureus and MRSA diseases, but the true prevalence of colonization is unknown.1-4,7-9 This prospective study looked at Staphylococcus aureus colonization in both populations of dolphins by sampling animals from various locations and testing for antibiotic-resistant bacteria. The overall objectives were to determine if healthy dolphins could be colonized by Staphylococcus aureus, if routine laboratory testing misidentified the bacteria, if the bacteria could be further classified as MRSA, and what spa types might colonize dolphins. While the number of animals sampled in this pilot study was small, the results were encouraging. The sampling methods represented the bacterial flora of dolphins isolating over 130 bacteria from fecal, blowhole and gastric samples. Two animals, one from each population, were identified as carriers of Staphylococcus aureus and one MRSA organism was identified using advanced PCR techniques. Genomic sequencing showed a spa type that is potentially pathogenic, but rarely encountered (0.11% of reported cases), in humans. Further research is ongoing to determine the prevalence of Staphylococcus aureus and MRSA in cetaceans and to better understand its relationship to human health.
* Presenting author
+ Student presenter
Literature Cited
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