Diphtheria and Tetanus (DT) Vaccine


Diphtheria is caused by bacteria.  Affected persons may have fever, sore throat with patches of greyish membrane adhered to the throat and breathing difficulty.  In serious cases, it can cause airway obstruction, heart failure, nerve damage or even death.  The disease is spread by contact with patient or carrier. Less commonly, a person may get infected through contact with articles soiled with discharges from affected persons.


Tetanus is caused by bacteria, which gets into the body through a break in the skin and produce a toxin that attacks the nervous system.  It can cause painful tightening of the body and locking of the jaws, so that the infected person cannot open his/her mouth or swallow.  When tetanus affects muscles that help to breathe, the patient can die very quickly.

Diphtheria and Tetanus (DT) Vaccine

A. Why get vaccinated?

DT vaccine can effectively prevent the above 2 serious diseases.  In Hong Kong, Diphtheria, Tetanus, acellular Pertussis & Inactivated Poliovirus Vaccine (DTaP-IPV Vaccine) is recommended for routine childhood vaccination.  However, children who cannot receive a pertussis-containing vaccine should be vaccinated with DT Vaccine.

B. When should my child get vaccinated?

In order to achieve good and lasting protection, a child should receive 3 doses of DT vaccine in the first year of life (at 2, 4 and 6 months), and another booster dose at 18 months of age.  Two other booster doses will be given to primary one and primary six students. DT vaccine can be given at the same time with other vaccines.

C. The following individuals should NOT receive DT vaccine

  • Serious allergic reaction to any of the vaccine components or following previous dose of DT vaccine
  • Serious allergic reaction to certain preservatives

D.  What are the side effects?

  • Most people have no serious reactions after receiving DT vaccine. Occasionally there may be mild fever (usually occur within 3 days after vaccination) or slight swelling around the injection site.  Parents can use anti-fever medication to relieve the symptoms.
  • If the child develops breathing difficulty or coma (which is extremely rare) after vaccination, please bring him/her to the Accident & Emergency Department of hospitals immediately for management

If you have any query, please contact Maternal & Child Health Centre of the Department of Health.

(Content revised 07/2017)