Active immunization against tetanus in guinea-pigs. An attempt to evaluate "rapid immunization" with tetanus vaccine.

The effect of 3 schedules for tetanus vaccination on the immunity developed by guinea-pigs was investigated, using 1.5 Lf adsorbed tetanus toxoid injected subcutaneously. The following injection schedules were used: a) 5 injections: initially and after 3, 7, 10, and 13 days; b) 3 injections:: initially and after 2 and 4 weeks; c) 2 injections: initially and after 4 weeks. Blood samples were taken after 1, 2, 3, 4, 6, and 8 weeks and the titres of tetanus antitoxin were recorded. No significant difference in the titres was observed within 2 weeks. Immunity was also tested by challenge with different amounts of tetanus toxin after 1 week, 10 days, 2, 3, and 8 weeks. A tendency to a higher immunity with schedule a) was observed after 10 days to 2 weeks; thereafter no acceleration of immunity could be shown. The results indicate that frequent injections over a short period of time do not establish rapid immunity against tetanus.