Testudines as sentinels for monitoring the dissemination of antibiotic resistance in marine environments: an integrative review

Dissemination of antibiotic resistance (AR) in marine environments is a global concern with a propensity to affect public health and many ecosystems worldwide. We evaluated the use of sea turtles as sentinel species for monitoring AR in marine environments. In this field, antibiotic-resistant bacteria have been commonly identified by using standard culture and sensitivity tests, leading to an overrepresentation of specific, culturable bacterial classes in the available literature. AR was detected against all major antibiotic classes, but the highest cumulative global frequency of resistance in all represented geographical sites was against the beta-lactam class by a two-fold difference compared to all other antibiotics. Wastewater facilities and turtle rehabilitation centres were associated with higher incidences of multidrug-resistant bacteria (MDRB) accounting for an average of 58% and 49% of resistant isolates, respectively. Furthermore, a relatively similar prevalence of MDRB was seen in all studied locations. These data suggest that anthropogenically driven selection pressures for the development of AR in sea turtles and marine environments are relatively similar worldwide. There is a need, however, to establish direct demonstrable associations between AR in sea turtles in their respective marine environments with wastewater facilities and other anthropogenic activities worldwide.