From October 2011 to December 2014, 11 swimmers reported bites by a sea lion or harbor seal. All bites involved the lower extremities. Because of the risk of Mycoplasma infection, treatment with a tetracycline is recommended in pinniped bites with signs of infection or serious trauma.
Nuckton, T.J., Simeone, C.A. and Phelps, R.T., 2015. California sea lion (Zalophus californianus) and harbor seal (Phoca vitulina richardii) bites and contact abrasions in open-water swimmers: a series of 11 cases. Wilderness & Environmental Medicine, 26(4), pp.497-508.