Early rabies antibody response to intramuscular booster in previously intradermally immunized travelers using human diploid cell rabies vaccine

Citation
Aw. Gherardin et al., Early rabies antibody response to intramuscular booster in previously intradermally immunized travelers using human diploid cell rabies vaccine, J TRAVEL M, 8(3), 2001, pp. 122-126
Citations number
17
Categorie Soggetti
General & Internal Medicine
Journal title
JOURNAL OF TRAVEL MEDICINE
ISSN journal
11951982 → ACNP
Volume
8
Issue
3
Year of publication
2001
Pages
122 - 126
Database
ISI
SICI code
1195-1982(200105/06)8:3<122:ERARTI>2.0.ZU;2-K
Abstract
Background: Postexposure treatment (PET) of travelers who may have had a po tential rabies exposure is simpler, safer, and cheaper if the traveler is p reimmunized. Preimmunization can be done with human diploid cell rabies vac cine (HDCV) administered intramuscularly or intradermally. Some authorities , however, are now advocating that travelers vaccinated by the intradermal (ID) route should be treated as if they are not immunized. A particular con cern raised is that travelers who have received pre-exposure rabies vaccina tion intradermally, may have a delayed response to postexposure boosters. T his study is designed to elucidate whether a single intramuscular (IM) HDCV booster will provoke an early (day 5) immune response in individuals given pre-exposure ID HDCV. Methods: Twenty-nine travelers who had received a course of three 0.1 mL ID HDCV between 12 and 24 months previously were given a single 1.0 mL IM boo ster of HDCV. Rabies antibody levels were compared 5 days later to those be fore the booster. Results: Twenty-five of the 29 subjects (86%) showed an adequate rise in vi rus neutralizing antibody (VNA) titer 5 days after booster. Nine of the 29 subjects (31%) had inadequate antibody levels prior to the simulated postex posure booster. Five days after the postexposure booster, 27 of 29 (93%) ha d adequate antibody levels. The other 2 travelers were subsequently shown t o have adequate VNA levels when tested 4 and 6 weeks later, respectively. Conclusion: For travelers who were given pre-exposure ID HDCV vaccination w ithin the last 2 years and received one IM postexposure booster dose of HDC V, most mounted an adequate early immune response. This data does not suppo rt a change in current recommendations for rabies PET in this group. Furthe r research to ascertain the duration of protection of pre-exposure ID rabie s immunization is required.