Please be aware that this information is provided to supplement the care provided by your physician. It is neither intended nor implied to be a substitute for professional medical advice. CALL YOUR HEALTHCARE PROVIDER IMMEDIATELY IF YOU THINK YOU MAY HAVE A MEDICAL EMERGENCY. Always seek the advice of your physician or other qualified health provider prior to starting any new treatment or with any questions you may have regarding a medical condition.

Diphtheria Vaccine

(DTaP Vaccine-Diptheria; Tdap Vaccine-Diptheria)
by Amanda Barrett, MA
What Is Diphtheria?

Diphtheria is a highly contagious and potentially life-threatening infection. It is caused by a bacterium called Corynebacterium diphtheriae . The germ produces a toxin that can spread from the site of infection to other tissues in the body. Diphtheria usually affects the throat and nose. In serious cases, it may affect the nervous system and heart.

Diphtheria spreads easily from person to person by coughing or sneezing. People nearby breathe in the infected droplets. In rare cases, they come into direct contact with excretions from an infected person’s mouth, nose, throat, or skin.

Because of a widespread immunization program, diphtheria is now rare in the US.

What Is the Diphtheria Vaccine?

The diphtheria vaccine is an inactivated toxin called a toxoid. There are different types of the vaccines to prevent diphtheria, including:

  • DTaP—given to children to protect against diphtheria, tetanus, and pertussis
  • DT—given to children who cannot receive the pertussis part of the DTaP vaccine
  • Tdap—given to children, adolescents, and adults to protect against tetanus, diphtheria, and pertussis
  • Td—given to adolescents and adults to protect against tetanus and diphtheria

The vaccine is injected into the muscle.

Who Should Get Vaccinated and When?
DTap

The DTaP vaccine is generally required before starting school. The regular immunization schedule is to give the vaccine at:

  • 15-18 months
  • 2 months
  • 4 months
  • 4-6 years
  • 6 months
Tdap

Tdap is recommended for:

  • Adults aged 65 years and older who have not been previously vaccinated and who have contact with babies aged 12 months or younger
  • Children aged 11-12 years who have completed the DTaP series
  • Children aged 7-10 years who have not been fully vaccinated
  • Pregnant women who have not been previously vaccinated
  • Teens and adults who did not get the Tdap when they were 11-12 years old
Td

Td is given as a booster shot every 10 years.

Catch-Up Schedule

If you or your child has not been fully vaccinated against tetanus, talk to the doctor. There are "catch-up" schedules based on age.

What Are the Risks Associated With the Diphtheria Vaccine?

Most people tolerate it well, but the diphtheria vaccine sometimes causes:

  • More serious complications:
    • Very rare: seizures associated with brain damage
    • Rare: allergic reactions, crying for over three hours, and high fever
  • Mild side effects: soreness or redness at the site of the injection, a low-grade fever, fatigue, general irritability, lack of appetite, and vomiting

Acetaminophen (eg, Tylenol) is sometimes given to reduce pain and fever that may occur after getting a vaccine. In infants, the medicine may weaken the vaccine's effectiveness. Discuss the risks and benefits of taking acetaminophen with the doctor.

Who Should Not Get Vaccinated?

There are two circumstances where the risks of the vaccine outweigh its benefits:

Since the diphtheria vaccine is generally given as DTaP, it can be hard to determine which component is causing a problem. It is usually best to avoid all three vaccines if there are serious side effects.

If your child has any of these reactions, you should get medical care right away:

  • Collapse with shock -like state (unresponsive with low blood pressure)
  • Convulsions, with or without fever, occurring within three days
  • Fever greater than 105ºF (40.5ºC)
  • Persistent, inconsolable crying lasting more than three hours
  • Severe swelling of the entire limb used for the vaccination

If your child has a moderate to severe illness, wait until he has recovered before getting the vaccine.

What Other Ways Can Diphtheria Be Prevented Besides Vaccination?

Prevention depends on getting the vaccine and responding quickly to outbreaks.

What Happens in the Event of an Outbreak?

Suspected cases of diphtheria need to be reported right away to public health authorities.

In the event of a suspected or confirmed outbreak, only close contacts are considered to be at risk. For close contacts, treatment includes:

  • Getting a booster dose if you have not had a dose in five years
  • Getting a dose right away if you have had fewer than three doses
  • Having samples taken for lab tests, taking antibiotics, and being followed closely for seven days (even if you have been vaccinated)

Last reviewed: December 2010 by David Horn, MD, FACP.

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