People who may be exposed to diphtheria in their jobs are recommended to receive a dose of either dT or dTpa vaccine if their last dose of diphtheria-toxoid vaccine was more than 10 years ago

Laboratory workers who may be exposed to toxigenic Corynebacterium diphtheriae in their jobs are recommended to have a serology test for diphtheria antibodies every 10 years. They should receive a booster dose of either dTpa or dT if the diphtheria antitoxin level is <0.1 IU per mL.

See Recommended vaccines for people at increased risk of certain occupationally acquired vaccine-preventable diseases in Vaccination for people at occupational risk.