Diphtheria

Diphtheria is a serious disease that can cause death through airway obstruction, heart failure, paralysis of the muscles used for swallowing and pneumonia. It is caused by the bacterium Corynebacterium diphtheriae, which produces toxins that cause cell death both at the site of infection and elsewhere in the body.

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 about one case of diphtheria occurs each year in the United States. However, in areas where the immunization rate has recently fallen (such as Eastern Europe and the Russian Federation), tens of thousands of people are suffering from diphtheria. The bacterium is still here—even though we do not see many cases. Our children are protected by being immunized and by everyone else being immunized too.

The diphtheria toxoid (inactivated toxin) vaccine offers the greatest protection against this disease. The fully immunized person who is exposed can become a carrier of the bacterium but 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.

Who Should and Should Not Receive the VaccineTop

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 who are younger than 7 years of age for whom there is a reason to not give a pertussis-containing vaccine, the TD can be administered. Children seven to nine years of age who are incompletely immunized, should receive Tdap. Previously unimmunized children between the ages of seven and nine, also should receive a dose of Td one to two months later and then another dose of Td 6 to 12 months later.

• Children between 11 and 18 years of age should receive a dose of Tdap. The preferred age for Tdap vaccination is 11-12 years. Detailed recommendations for the use of Tdap for preteens and adolescents are available from the CDC.

• Adults 19-64 years of age should also receive a single dose of Tdap (ADACEL) to replace a single dose of Td for booster immunization if their most recent tetanus toxoid-containing vaccine was 10 or more years earlier. Tdap may be given at an interval shorter than 10 years since the last tetanus and diphtheria toxoids-containing vaccine in order to protect against pertussis, especially for:

  • Women <65 years of age who might become pregnant.

  • Women who have not previously received Tdap (including those who are breast feeding) should receive Tdap as soon after birth as is feasible. Many experts also recommend that Tdap be considered for pregnant teenagers.

  • Adults who have or anticipate having close contact with an infant aged <12 months should receive a single dose of Tdap and trivalent inactivated influenza vaccine. Ideally the vaccines should be given at least 2 weeks before contact.

  • Health-care personnel who have direct patient contact should receive a single dose of Tdap.

• Td vaccine should be administered every 10 years to provide continued immunity against diphtheria and tetanus.

Who should not receive the vaccine?

• Those with a history of a serious allergic reaction (such as anaphylaxis) to any of the vaccine components.

• Those with a history of encephalopathy (e.g. coma or prolonged seizures) not attributable to an identifiable cause within 7 days of administration of a vaccine with pertussis components should not receive a pertussis-containing vaccine.

People with the following conditions should discuss with their health care professional whether they should receive these vaccines:

• 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.

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.

Hib

Haemophilus influenzae type b (Hib) is a bacterium that can infect the outer lining of the brain causing meningitis. Hib is transmitted from person to person through mucus droplets that are spread by coughing or sneezing. Invasive Hib disease occurs most often at three months to three years of age, peaking at six to seven months of age. The disease is uncommon after age five years.

Hib can cause a wide variety of serious infections, including pneumonia, severe throat swelling that makes breathing difficult (epiglottitis), and infections of blood, bones, joints, and the covering of the heart. Complications of Hib meningitis include blindness, deafness, mental retardation, learning disabilities, and death. About 5% of children (500 out of every 10,000) with Hib meningitis die despite antibiotic treatment.