Seroimmunity to Tetanus and Diphtheria among Immunocompetent Adult Patients Admitted to a Tertiary Hospital for Any Reason

Ignoring the importance of receiving booster doses of vaccines in vast majority of adults could result in their lack of immunity against tetanus and diphtheria. In this prospective cohort study all immunocompetent adults ≥ 40 years old who were admitted for any reason during the time period of the survey were enrolled and antibody levels against tetanus and diphtheria were measured. 84 patients (48%) were 40 - 60 years old and 93 (52%) subjects aged older than 60 years. In general, anti-tetanus antibody titer was <0.1 IU/mL (non-immune range) in 83 people (46.9%). For anti-diphtheria antibody, 74 (41.8%) were considered non-immune. Of all people whose tetanus antibody level was <0.1, 19 had a complete history of childhood diphtheria and tetanus immunization and 64 had unknown vaccination history. Among people with diphtheria antibody levels < 0.1, 18 (24.3%) had complete history of childhood vaccination and 56 (75.6%) had unknown history.