Although the exposure of HK leukocytes to inactivated VHSV in vitro was not capable of significantly increasing the percentage of IgM+ B cells expressing CD38A on the cell membrane nor that of cells expressing CD38A without IgM, a bath infection with VHSV significantly up-regulated the levels of transcription of both CD38 homologues in the HK. The gene discussed is CD38; the disease is infection.