First Detection of Hemotropic Mycoplasma sp. in Cetaceans of European Waters

Mycoplasma spp. are wall-less bacteria classified as hemotropic (hemoplasmas) and non-hemotropic that can cause disease and death in immunosuppressed hosts. While hemoplasmas have been described in cetaceans of the Americas, their presence in cetaceans of Europe remains unknown. In this study, we surveyed hemoplasma in cetaceans stranded in Cantabria (n = 20) and the Valencian Community (n = 48), Spain. Specifically, we used real-time PCR to test spleen and lung samples from 68 cetaceans of the families Delphinidae (n = 60), Phocoenidae (n = 4), Kogiidae (n = 3), and Ziphiidae (n = 1). Overall, 11.8% (8/68) were Mycoplasma-positive, all striped dolphins (Stenella coeruleoalba) of the Valencian Community. Two nucleotide sequence type (STs) were detected; one was identical to a hemoplasma from a short-beaked common dolphin (Delphinus delphis) from Brazil, and the other showed 96.1% nucleotide identity with hemoplasma previously found in Bolivian river dolphins (Inia boliviensis), raccoons (Procyon lotor), and Candidatus Mycoplasma haemolamae of llamas (Lama glama) and alpacas (Vicugna pacos). Our findings broaden the known geographic range of hemoplasma in cetaceans, reporting for the first time its presence in dolphins in Europe. The health impacts of the detected hemoplasmas in cetaceans are still unknown.