Twenty-two herpesviruses, all within the family Orthoherpesviridae and belonging to the Alphaherpesvirinae (n = 3) and Gammaherpesvirinae (n = 19) subfamilies have been reported in 14 different pinniped species (n = 8 phocids, n = 5 otariids and n = 1 odobenid). This review critically assessed the purported pathology reported for herpesvirus infections and found a variety of lesions present dependent on both the herpesvirus and host species. Lesions included hepatic and adrenal necrosis, interstitial pneumonia, thyroid atrophy, lymphodepletion, lymphocytolysis, ulcerative stomatitis, glossitis with tonsilitis and dermatitis, necrotizing keratitis and, potentially, other ocular lesions also. Furthermore, specific individual gammaherpesvirus infections were linked to oncogeneses including urogenital carcinoma, diffuse large B cell lymphoma and B cell lymphoblastic lymphoma. However, for many herpesvirus infections the clinical significance, lesion association and definitive herpesvirus classification remain uncertain, the latter due to lack of sufficient genome data. For these reasons, identification of the definitive host species or even if separately reported herpesviruses are actually the same virus, remain challenging. More extensive genome sequencing is required to definitively identify and classify individual herpesvirus species along with sensitive and specific tools to visualize them within tissues to enable investigation of lesion association.
Robinson et al. (Thu,) studied this question.