Tetanus is an infection transmitted by Clostridium tetani bacteria. The bacteria lives in mud, soil and dust, but can also be present in human and animal feces. The bacteria can enter the body through any open wound, even small ones, and infect the nerves that control the muscles, causing severe muscle pain and spasms. Without appropriate hospital treatment, tetanus can be fatal. The best protection against tetanus is the vaccine, which is included in Quebec’s child immunization program. The anti-tetanus test checks to see if an individual is adequately protected against tetanus. Results are expressed in international units of anti-tetanus antibodies per millilitre of blood (IU/ml), and levels equal to or greater than 0.01 IU/mL are considered sufficient for adequate protection.
Anti-tetanus levels below 0.01 IU/mL are insufficient to protect a person against tetanus and may indicate who should be vaccinated, if applicable. It usually takes two to three weeks after vaccination to measure whether the body’s response to the vaccine was adequate. The absence of antibodies following vaccination may be associated with a weak immune system or may be caused by the use of immunosuppressive drugs.