An unusual reaction to rabies vaccine.

This report describes a previously undescribed reaction to human diploid cell rabies vaccine (HDCV). The vaccine is available for prophylaxis against Australian bat lyssavirus (ABL) infection both prior to and after possible exposure. Australian bat lyssavirus is the most recent lyssavirus to be discovered and has been linked to at least one death in Queensland. HDCV appears to be effective against the virus. A 27-year-old man was scratched on the right shoulder on 22 March 1999 by an unidentified bat while he was at work on a construction site. He was assessed at his local hospital and, following consultation with the Public Health service, was given rabies immunoglobulin and one ampoule of HDCV. He was discharged and given instructions to return for further doses on days 3, 7, 14 and 28 following the first injection. The vaccine administered to this patient was rabies strain Pitman-Moore/W 1381503-3M cultured on human diploid cells and inactivated by ß-propiolactone. Each injection contains 2.5 IU of the virus. It is indicated for prophylaxis against ABL both prior to and subsequent to potential exposure and is administered intramuscularly. He presented to the Mt Isa Base Hospital for the day three injection. He reported that following the first injection, he had experienced transient neurological symptoms for 30–60 minutes. These included blurred vision and occipital numbness and resolved spontaneously. He was given the day three vaccine, observed for 90 minutes and discharged. Visual acuity following injection was recorded on this occasion and was 6/36 in both eyes. He presented for the third injection on 31 March 1999 and repor ted the same symptoms following the second injection as those that occurred after the first. However, on this occasion, the symptoms had lasted for nearly 2 days. Approximately 30 minutes after the third injection, he developed blurred vision, light-headedness and occipital numbness, as well as tingling over the left parieto-temporal region. Examination revealed a thin, fully orientated young man with stable haemodynamic parameters and a GCS of 15. Visual acuity was 6/60 in both eyes, correctable to 6/36 with pinhole. He had a left horizontal nystagmus and a positive Romberg's sign. Gait, coordination and the remaining neurological and general examination were normal, as well as fundoscopy. At this point, advice was sought from the regional Public Health Unit as well as from a clinical microbiologist. While the literature at that time had reported no permanent neurological deficits linked to …