PHOCINE DISTEMPER VIRUS

Tavishi Phocine distemper virus, or PDV, is a morbilivirus causing infection and mortality within pinnipeds. PDV is very, very similar to the commonly known canine distemper virus, and it's very likely that PDV developed from CDV. PDV is also related to measles, which is another type of morbilivirus. Below are a group of harbor seals.

These seals do not have PDV. They are, however, very cute. PDV was first observed in Baikal seals in 1987, following an unusual mortality event. At first, PDV was mistaken for canine distemper, but was later recognized as its own virus. Aside from that, PDV has been detected in many northern pinniped species including the gray seal, harbor seal, harp seal, and ringed seal. In pinnipeds, PDV presents with nasal discharge, conjunctivitis, keratitis, coughing, mucosal cyanosis, lethargy, and depressive symptoms. Generally, discharge appears mucopurulent, or kinda greenish/yellowish- opaque discharge. Keratitis and conjunctivitis are both characterized by ocular discharge and swelling. However, keratitis affects the cornea and conjunctivitis affects the conjunctiva. Mucosal cyanosis is a lack of oxygen to mucosal membranes causing blue coloration. In some patients, seizures and convulsions are present.

Above is a gray seal pup. Cute. PDV replication begins in T and B lymphocytes before then spreading around the body to endothelial tissues, and worst of all, the central nervous system. PDV can be diagnosed based off of histopathological examinations of tissue. These examinations look for ICIBs, or intracytoplasmic inclusion bodies, and INIBS, or intranuclear inclusion bodies. Inclusion bodies are protein clumps that indicate a viral infection; in this case, where PDV has been found in cells, generally indicating a site of viral replication. The stain used for these tissue samples is generally hematoxylin and eosin, detecting the acidophilic and amphophilic inclusion bodies. Acidophilic inclusion bodies are also known as eosinophilic, as they'll appear the pinkest in response to the acidic dye eosin. Amphophilic inclusion bodies respond to both hematoxylin and eosin, and generally appear purplish-blue. (Should I do a histology Kradigan series?) Other methods of diagnosis include ELISA, RT-PCR, and more.

Vaccination in the wild has been done to protect the especially vulnerable Hawaiian monk seal- the Hawaiian monk seal is endangered, and PDV can be extremely deadly. Vaccination of wild animals prior to infection is crucial to create herd immunity.

In his sleep, he is vaccinated. Mwahahaha.