Close and frequent contact between cleaner and host species creates ample opportunity for transfer of infectious organisms. Based on the observation that reef cleaner fish bite tumors of green turtles, we hypothesized that such reef fish may serve as carriers or vectors for the transmission of GTFP. To determine the role of reef cleaner fish in GTFP. DNA prepared from various tissues and organs (including snout, gill, eye, brain, heart, liver, gut content, intestine, swim bladder, spleen, gall bladder, spinal cord, gonad, and muscle) of six healthy-appearing saddleback wrasse (Thalassoma duperrey), captured from a cleaning station in North Kaneohe Bay, Oahu, Hawaii, were tested for evidence of GTHV infection by nested polymerase chain reaction. GTHV sequences were detected in snout (3/6), gill (2/6) and liver (1/6). All other tissues were negative. Except for a single nucleotide substitution (from A to G at position 48 which resulted in an single amino acid change from isoleucine to methionine at position 16), the DNA sequences detected in the fish were identical to that of a newly reported GTHV. Although preliminary, these data represent the first evidence for an association of a herpesvirus with saddleback wrasse, suggesting that cleaner fish may serve as vectors or carriers for the transmission of the agent causing GTFP.