IMMUNE STATUS AND BOOSTER EFFECTS OF LOW-DOSES OF TETANUS TOXOID IN SWEDISH MEDICAL PERSONNEL

Of 102 medical staff at a Swedish hospital, 81% had tetanus antitoxin titres greater than or equal to 0.01 IU/ml in 1984-85. The unprotected individuals (antitoxin titre <0.01 IU/ml) were all >30 years of age. Of this group, one-third lacked a protective antibody level against tetanus toxin. Low booster doses of tetanus toroid (0.75 or 1.9 Lf) were given to 66 vaccinees with a history of previous basic vaccination and no history of booster vaccination within the previous 5 years. The median titre increased from 0.26 IU/ml before to 3.3 IU/ml after vaccination. Low doses of tetanus toroid may thus still provide an adequate immune response when given as a booster vaccination to individuals with a reliable history of basic immunization.