Seroprotection after hepatitis a vaccination in patients with drug-induced immunosuppression

Increasing numbers of travelers using immunosuppressive drugs visit hepatitis A endemic countries. Data on protection rates after hepatitis A vaccination in this group are scarce.

In this retrospective study, records of subjects with hepatitis A serology taken after vaccination were searched for in travel clinic databases. Relation between immunosuppressive drug use, age, gender, and time between vaccination and serology was evaluated.

Seroprotection rates within 4 weeks after primary vaccination (50%) are lower than after 4 weeks (64%). After the complete series of two vaccinations seroprotection rates reach 95% although success depends on the immunosuppressive drug being used. Subjects under anti-TNF alpha treatment have significantly lower seroprotection rates than subjects using classical immunosuppressive drugs after the second vaccination. There is no influence of age or gender on seroprotection rates.

Last-minute vaccination in subjects using immunosuppressive medication is not reliable, only 60% of our subjects had a protective antibody level after a single vaccination. When serology was done within 4 weeks after a single vaccination, seroprotection rates were only 50%, after 4 weeks this number rose to 64%. When persons visit a travel clinic in time for a complete vaccination series, satisfactory seroprotection rates can be reached. Seroprotection rate depends on the drug being used, persons using anti-TNF alpha are less protected.