Search: Go
Immunization Science
Immunization Issues
Vaccines and the Diseases they Prevent
Health Professionals
About NNii

Vaccine Information


Entry last updated: March 12, 2004

- Understanding the Disease
- Available Vaccines
- History of the Vaccine
- Who Should and Should Not Receive the Vaccine
- Dose Schedule
- Effectiveness of the Vaccine
- Known Side Effects
- Related Issues
- Key References and Sources of Additional Information
- State Vaccine Requirements
- Important Facts for Parents to Know
- Frequently Asked Questions
- CDC Vaccine Information Statement

Understanding the Disease

Diphtheria is a serious disease that can cause death through airway obstruction, pneumonia, heart failure, and paralysis of the muscles used for swallowing.

Diphtheria usually begins with a sore throat, slight fever, and swollen neck. Most commonly, bacteria multiply in the throat, where a grayish membrane forms. This membrane can choke the person. Sometimes, the membrane forms in the nose, on the skin, or other parts of the body. The bacteria can release a toxin that spreads through the bloodstream and may cause muscle paralysis, heart and kidney failure, and death. Approximately 5% of people who develop diphtheria (500 out of every 10,000) die from the disease and many more suffer permanent damage.

In the 1920s, before the diphtheria vaccine, there were 100,000 to 200,000 reported cases in the United States each year. Because of the high level of immunization, only one case of diphtheria was reported in the United States in 1999. However, in areas where the immunization rate has fallen (such as Eastern Europe and the newly independent states of the former Soviet Union), tens of thousands of people suffered from diphtheria in recent years.

The diphtheria vaccine offers the greatest protection against this disease. The fully immunized person who is exposed can become a carrier of infection, may only develop a mild case, or may not get sick at all. But if not fully vaccinated, the risk of getting� severely ill is 30 times higher.

Available Vaccines

No diphtheria-only vaccine is available. The diphtheria vaccine is available as:

  • DTaP (Diphtheria-Tetanus-acellular Pertussis vaccine)
  • DTaP in combination with Haemophilus influenzae type b (Hib) vaccine
  • DTaP in combination with hepatitis B and inactivated polio vaccines
  • DT or Td (in combination with tetanus vaccine)

Vaccines containing the whole-cell pertussis component (DTP) are no longer recommended in the United States and are, therefore, not listed here.

All DTaP vaccines are available containing no or only trace amounts of thimerosal. For information on the thimerosal content vaccines, see the Food and Drug Administration at

Product Name: Diphtheria and tetanus toxoids adsorbed� (DT)
Manufacturer: Aventis Pasteur
Year licensed: 1984

Product Name: Tetanus and diphtheria toxoids adsorbed for adult use (Td)
Manufacturers (Year licensed): Massachusetts Public Health Biologic Laboratories (1970), Aventis Pasteur (1978)

Product Name: Tripedia� (DTaP)
Manufacturer: Aventis Pasteur
Year licensed: 2001

Product Name: Infanrix� (DTaP)
Manufacturer: GlaxoSmithKline
Year licensed: 1997

Product Name: TriHIBit� (DTaP and Hib conjugate vaccine)
Manufacturer: Aventis Pasteur
Year licensed: 2001

Product Name: DAPTACELTM (DTaP)
Manufacturer: Aventis Pasteur
Year Licensed: 2002

Product Name: PediarixTM (DTaP, hepatitis B, and inactivated polio vaccines)
Manufacturer: GlaxoSmithKline
Year licensed: 2002

History of the Vaccine

In the mid-1940s, the diphtheria vaccine was combined with vaccines against tetanus and pertussis.� The combined DTP vaccine soon was routinely used in the United States, but is no longer recommended.

In 1991, the Food and Drug Administration licensed the DTaP (diphtheria-tetanus-acellular pertussis) vaccine.� While DTP vaccine was made using whole cells of the pertussis germ, DTaP is made using only small, purified pieces of the germs.� Fewer side effects have been reported with the DTaP vaccine than with DTP.� In 1991, DTaP was licensed for only the fourth and fifth doses in the series, and in 1997 it was licensed for all five doses. DTP is no longer recommended for use in the United States but is widely used in other countries; it is equally effective.

Who Should and Should Not Receive this Vaccine

Who should receive the vaccine?

  • Most infants and children younger than seven years of age should receive DTaP beginning at two months of age.
  • For children seven years of age and older, the Td vaccine should be administered every 10 years to provide continued immunity against diphtheria and tetanus.�

Who should not receive the vaccine?

  • Pertussis vaccines (including the DTaP vaccine) are not currently recommended for children after they reach their seventh birthday because pertussis is not a life-threatening disease in older children and adults, though they often spread the disease to infants and young children. Studies are currently being undertaken to determine the safety and efficacy of DTaP when given after age six; preliminary data suggests that the vaccine is safe and effective in adolescents and adults.�

People with the following conditions should discuss with their health care professional whether they should receive DTaP vaccine:

  • Moderate or serious reaction after receiving DTP or DTaP in the past
  • Seizure or have a parent or sibling who has had a seizure (the risk of fever and seizure is much less with the new DTaP vaccines than with DTP).
  • Brain problem that is unstable or getting worse
  • People who are moderately or severely ill should consult with their physician before receiving any vaccine.

This vaccine is recommended by:

  • Advisory Committee on Immunization Practices of the Centers for Disease Control and Prevention
  • American Academy of Pediatrics
  • American Academy of Family Physicians

The complete childhood immunization schedule can be found at:

The summary of adolescent/adult immunization recommendations can be found at:

Dose Schedule

The DTaP vaccine�or DTaP, hepatitis B, and inactivated polio vaccines (PediarixTM1, GlaxoSmithKline)�is given to most children at two, four, and�six months of age. PediarixTM can only be given for the first three doses a child receives.

A fourth dose of DTaP�or DTaP and Hib conjugate vaccine (TriHIBit�, Aventis Pasteur)�is given between 15 and 18 months, and a fifth dose is given at age�four to six years. If the fourth dose was given after age four years, then no fifth dose is needed. TriHIBit� can only be given for these booster doses, not for the initial three doses.

Receiving combination vaccines from different manufacturers, which may include different component vaccines, can make the dose schedule more complex.� However, since giving combination vaccines means fewer shots overall for a child, healthcare providers will usually choose to administer them.� Healthcare professionals should attempt to select vaccines for their patients, especially children who have been seen by other practices, based on what they have already been given.

Children younger than age seven who should not receive the pertussis vaccine should receive the DT (diphtheria-tetanus) vaccine. At age seven or older, Td (tetanus-diphtheria), which contains the same amount of tetanus vaccine as in DTaP or DT, but contains much less diphtheria toxoid, is given to protect against tetanus and diphtheria.

The Td vaccine is given to unimmunized children age seven and older instead of DTaP (or any combination vaccine that includes a pertussis component).� Two doses are given one to two months apart, and a third dose should be given 6 to 12 months after the second dose.

At age 11-12 years, a booster dose of tetanus-diphtheria (Td) is needed. For best protection of the child, Td should be given by age 16. Every 10 years thereafter, a booster of Td is needed to maintain protection against diphtheria and tetanus.

1 NNii uses vaccine trade names only for clarity in our presentation of immunization recommendations. NNii does not recommend specific vaccine brands over others.

Effectiveness of the Vaccine

The DTaP vaccine is 95% effective in preventing all three diseases that it immunizes against--diphtheria, tetanus and pertussis. It is also about 95% effective in preventing diphtheria, while the protection rates are lower for pertussis and higher for tetanus. Immunity against diphtheria lasts about 10 years; therefore a booster dose of Td (tetanus-diphtheria) vaccine is needed every 10 years to maintain immunity. If exposed to diphtheria, partially immunized individuals can acquire the disease, although generally it is less severe than in unimmunized people.

Known Side Effects

Half of those vaccinated with DTaP will experience no side effects at all. About half of those vaccinated will experience mild reactions such as soreness where the shot was given, fever, fussiness, reduced appetite, tiredness, or vomiting. The risk of fever and seizure is much less with the new DTaP vaccines than with DTP. Because of decreased vaccine reactions with DTaP compared with DTP, the DTP vaccine is no longer recommended in the United States. Some children may experience a temporary swelling of the arm or leg where DTaP was given; this reaction is more common after the fifth dose of DTaP.

DTaP is now recommended because the rate of serious reactions to the DTaP vaccine is lower than with DTP; however, if a person has had immediate anaphylaxis, or encephalopathy within 7 days following DTP, they should not be given DTaP.

In rare cases (about 100 children out of 10,000 shots given, or about 1%) children have moderate reactions such as prolonged crying, fever of 105 degrees or higher, seizure, or the child becoming limp, pale, and less alert. The decision to administer additional dose of a pertussis containing vaccine should be considered carefully.

In very rare cases (less than 1 out of every 10,000 shots given, or about .003%) children have serious reactions such as breathing difficulty, shock, or severe brain reaction (brain inflammation, long seizure, coma or lowered consciousness). These adverse reactions are usually due to the vaccine's pertussis component; therefore, doctors advise that infants and children who experience these adverse reactions to DTaP should receive DT for each of the remaining doses in the primary series.

Studies have shown that children who receive the Hib vaccine in combination with or at the same time as the DTaP vaccine are no more likely to experience side effects than children who only receive the DTaP vaccine.

Related Issues

Questions about the relationship between the DTP vaccine and the incidence of Sudden Infant Death Syndrome (SIDS) have arisen. Scientific investigations have shown no causal relationship between the DTP or DTaP vaccines and Sudden Infant Death Syndrome (SIDS).

For more information, see:

Key References and Sources of Additional Information

  • American Academy of Pediatrics, Committee on Infectious Diseases. (2003). Red Book: Report of the Committee on Infectious Diseases (26th ed.). Elk Grove Village, IL: Author.
  • Atkinson W, Wolfe C, Humiston S, and Nelson R (Eds.). (2000). Diphtheria. In Epidemiology and prevention of vaccine-preventable diseases. (The Pink Book). (6th ed.). Atlanta: Centers for Disease Control and Prevention. Available on-line:
  • Centers for Disease Control and Prevention (CDC). (1991). Diphtheria, tetanus, and pertussis: Recommendations for vaccine use and other preventive measures: Recommendations of the Immunization Practices Advisory Committee (ACIP). Morbidity and Mortality Weekly Report (MMWR), 40( RR-10), 1-28.
  • CDC. (1997). Vaccine Information Statement (VIS). Available on-line:
  • CDC. (2000). Recommended childhood immunization schedule - United States, January-December, 2001 (Approved by the ACIP, AAP, and AAFP). MMWR, 49(2), 35-38, 47.
  • CDC, National Immunization Program. (2000). Vaccine-preventable childhood diseases�- Diphtheria. Available on-line:
  • Combination Vaccines for Childhood Immunization: Recommendations of the Advisory Committee on Immunization Practices (ACIP), The American Academy of Pediatrics (AAP), and the American Academy of Family Physicians (AAFP). (1999). Pediatrics, 103(5). Available online:
  • Food and Drug Administration. (2002). Product approval information � Licensing action. Available online:
  • Humiston SG and Good C. (2000). Vaccinating your child: Questions and answers for the concerned parent. Atlanta: Peachtree Publishers.
  • Offit PA and Bell LM. (1999). Vaccines: What every parent should know (revised edition). New York: IDG Books.

Also see our image gallery of diseases.

Including available vaccines, history of the vaccine, who should and should not receive it, dose schedules, effectiveness, known side effects, and related issues.

Diphtheria Vaccine State Requirements

Check to see if your state requires this vaccine.

Important Facts for Parents to Know about the Diphtheria Vaccine

A fact sheet that gives basic information on this disease, as well as the effectiveness and possible side effects of the vaccine that can prevent it.

Frequently Asked Questions about the Diphtheria Vaccine

A fact sheet with in-depth answers to common questions about this vaccine.

CDC Vaccine Information Statement for Diphtheria

Information provided by the Centers for Disease Control and Prevention on specific vaccines and the diseases they can prevent. Healthcare providers are required to give these to their patients before administering a vaccine.

Home�|�About NNii�|�Contact Us�|�Contribute�|�Disclaimer�|�Site Map