IN medically important infections with cytopathic viruses, neutralizing antibodies are generated within 6–14 days. In contrast, such protective antibodies appear late (50–150 days) after infection with immunodeficiency virus (HIV) and hepatitis B virus (HBV) in humans, or lymphocytic choriomeningitis virus (LCMV) in mice^1–6. However, during these infections, non-neutralizing antibodies appear much earlier^2,6,7. It has been proposed that T cells suppress antibody responses generally and against viruses in vitro^6,8–10. Here we show that the suppression of neutralizing-antibody responses in LCMV infections in mice is due to selective infection of neutralizing-antibody-producing B cells by this non-cytopathic virus, and their subsequent destruction by virus-specific cytotoxic T cells. Such specific B-cell elimination that leads to a delay in neutralizing-antibody production could help to establish persistent virus infections by non-cytopathic viruses.