Three instances of delayed HIV seroconversion occurring in health-care workers have been reported;[10] in these instances, the health-care workers[11] tested negative for HIV antibodies greater than 6 months postexposure but were seropositive within 12 months after the exposure.[12] DNA sequencing confirmed the source of infection in one instance. Two of the delayed seroconversions were associated with simultaneous exposure to hepatitis C virus (HCV). In one case, co-infection was associated with a rapidly fatal HCV disease course; however, it is not known whether HCV directly influences the risk for or course of HIV infection or is a marker for other exposure-related factors.
