Most adverse events (AEs) during the immunization of rabies vaccine were slight, there was little information about the allergic reaction induced by rabies vaccines and had to stop or change the immunization program. Here, we reported a case that a 4-year-old boy had category II exposure to rabies and showed severe allergic reaction after being immunized with lyophilized purified vero cell rabies vaccine (PVRV). After the anti-allergy therapy with hormone, allergy testing indicated medium allergy to egg and milk, and implied the allergic reaction most likely associated with animal-sourced gelatin in lyophilized PVRV. Therefore, a new immunization program with liquid PVRV without stabilizers under the Zegrab regimen (2-1-1) was enrolled at day 7 post-exposure. Although lower than the levels of normal <5 -year population at day 14 and 45, the neutralizing antibody (RVNA) titers of this boy showed adequate protective antibody (≥ 0.5 IU/ml), even after 365 d post-immunization. This study not only highlighted the importance of several types of rabies vaccines co-existing in the market, but also implied the necessary for doctors to fully understand the allergies history of patients prior to immunize rabies vaccine.
Keywords: allergic reaction; neutralizing antibody (RVNA) titer; purified chick embryo cell vaccine (PCECV); purified vero cell rabies vaccine (PVRV); rabies virus neutralizing antibody (RVNA).