title: Effects of ocular surface strontium-90 beta radiotherapy in dogs latently infected with canine herpesvirus-1.
abstract: Latent canine herpesvirus-1 (CHV-1) infections are common in domestic dogs, but stimuli causing viral reactivation and recrudescent disease are poorly understood. Immunosuppressive pharmaceuticals are currently the only experimentally established triggers for recurrent ocular CHV-1 infection in dogs; however, ocular CHV-1 shedding has been reported clinically following strontium-90 beta radiotherapy of the ocular surface and it has been speculated that radiotherapy can directly induce viral reactivation. Strontium-90 is used as a beta radiation source for the treatment of a variety of neoplastic and immune-mediated canine ocular surface diseases. In the present study, the effects of ocular surface strontium-90 beta radiotherapy in dogs latently infected with CHV-1 were evaluated. Ten mature dogs with experimentally induced latent CHV-1 infections were randomly divided into two groups: one group received a single fraction 50 Gy radiation dose in one application from a strontium-90 ophthalmic applicator and the second group received sham radiotherapy. Dogs were then monitored for 45 days for recurrent ocular CHV-1 infection using clinical and virological outcome measures. Clinical ophthalmic examinations, ocular sample CHV-1 PCR assays, and serum CHV-1 virus neutralizing antibody assays were performed at specified intervals. No abnormalities suggestive of recurrent CHV-1 ocular disease were observed on clinical examination in any dog during the study. Ocular viral shedding was not detected and CHV-1 virus neutralizing titers remained stable in all dogs. A single fraction 50 Gy radiation dose administered to the ocular surface by strontium-90 beta radiotherapy did not result in detectable recurrent ocular CHV-1 infection in mature dogs with experimentally induced latent infection.
authors.affiliation: Cornell University, College of Veterinary Medicine, Department of Clinical Sciences, Ithaca, NY 14853, United States.
authors.forename: Amanda M
authors.initials: AM
authors.lastname: Nicklin
authors.affiliation: Cornell University, College of Veterinary Medicine, Department of Clinical Sciences, Ithaca, NY 14853, United States.
authors.forename: Margaret C
authors.initials: MC
authors.lastname: McEntee
authors.affiliation: Cornell University, College of Veterinary Medicine, Department of Clinical Sciences, Ithaca, NY 14853, United States. Electronic address: ecl32@cornell.edu.
authors.forename: Eric C
authors.initials: EC
authors.lastname: Ledbetter
mesh_terms: D000818:Animals; D001610:Beta Particles / Q000009:adverse effects; D004283:Dog Diseases / Q000821:virology*; D004285:Dogs; D005123:Eye / Q000821:virology; D005128:Eye Diseases / Q000662:veterinary* / Q000821:virology; D005260:Female; D006566:Herpesviridae Infections / Q000662:veterinary* / Q000821:virology; D002184:Herpesvirus 1, Canid / Q000502:physiology* / Q000528:radiation effects; D008297:Male; D012008:Recurrence; D013326:Strontium Radioisotopes / Q000009:adverse effects; D019562:Viral Load / Q000528:radiation effects / Q000662:veterinary; D017201:Virus Shedding / Q000528:radiation effects
chemical_list: D013326:Strontium Radioisotopes
keywords: Beta radiation; Canine herpesvirus-1; Dog; Recrudescent disease; Strontium-90 radiotherapy