Transmission electron micrographs of OsHV-1 infected tissues from Pacific oyster spat. A: enveloped particles (arrows) and L-particles (arrows head) detected in adductor muscle tissue. Scale bar = 1 μm; B: capsids (arrows) and nuclocapsids (arrows head) detected in the nucleus of an infected cell in the mantle. Scale bar = 2 μm; C: high magnification of capsids (arrows) and nucleocapsids (arrows head) present in the nucleus of a mantle cell from an infected oyster. Scale bar = 500 nm; D: high magnification of L-particles detected in the mantle of an infected oyster. Scale bar = 1 μm.