Ostreavirus is a genus of viruses in the order Herpesvirales, and one of only two genera in the family Malacoherpesviridae.

A disease associated with this genus is sporadic episodes of high mortality among larvae and juveniles.

[1][2][3] Acute viral necrosis virus, which affects scallops such as Chlamys farreri, appears to be a variant of Oyster herpesvirus.

[5] Ostreavirus is enveloped, with spherical to pleomorphic geometry, and T=16 symmetry.

The genome is linear and non-segmented, around 134kb in length.