DTaP vaccine
The DTaP vaccine is a combined immunization that protects against three serious bacterial diseases: diphtheria, tetanus, and pertussis (whooping cough). Diphtheria is caused by the bacterium *Corynebacterium diphtheriae*, leading to severe throat issues; tetanus, from *Clostridium tetani*, causes painful muscle contractions; while pertussis, triggered by *Bordetella pertussis*, results in a debilitating cough. The vaccine works by using inactivated forms of the toxins produced by these bacteria, stimulating an immune response without causing disease. Initially licensed in 1948, the DTaP vaccine has evolved, particularly in 1991, when the acellular pertussis component was introduced to reduce side effects.
Children are typically vaccinated at two, four, six, and fifteen to eighteen months, with a booster given between four and six years of age. Adolescents and adults then receive a Tdap booster, which has lower doses of diphtheria and pertussis components, with Td boosters recommended every ten years thereafter. The DTaP vaccine significantly reduced occurrences of diphtheria and tetanus in the U.S., although pertussis remains a concern, particularly among infants and adults whose immunity may wane over time. The ongoing challenge of vaccine hesitancy has raised concerns about the future public health achievements related to these preventable diseases.
DTaP vaccine
- ALSO KNOWN AS: Diphtheria, tetanus, and acellular pertussis vaccine
Definition
The DTaP vaccine protects against three different bacterial illnesses. The first disease, diphtheria, is caused by the bacterium Corynebacterium diphtheriae. Infection with this bacterium causes a severe sore throat and difficulty breathing and swallowing. The second disease, tetanus, is caused by the bacterium Clostridium tetani and leads to what is commonly referred to as lockjaw. This disease causes intense muscle contractions and can interfere with breathing. The last disease, pertussis, or whooping cough, is caused by the bacterium Bordetella pertussis. This bacterium produces a severe persistent cough with a characteristic whooping sound on inspiration between coughing fits and can lead to respiratory failure.
Mechanism of Action
The vaccine incorporates the three toxins produced by the bacteria in their inactivated forms (known as toxoids). These toxoids are then administered, leading to an immune response without causing the disease, protecting from future illness.
History
Individual vaccines against diphtheria, tetanus, and pertussis were first developed in the late nineteenth and early twentieth centuries. The combination vaccine that incorporated all three was first licensed in 1948. The vaccine was further modified in 1991 in response to a high rate of side effects thought to be caused by the original whole-cell pertussis component. A new, acellular pertussis element was developed at that time and has resulted in a significant decrease in the side effect profile of the vaccine. The DTaP vaccine can be found as a component of combination vaccines such as Pediarix (with hepatitis B and inactivated poliovirus) and Pentacel (with Haemophilus influenzae type B and inactivated poliovirus).
Administration
Following the recommended vaccination schedule is crucial for ensuring maximum protection. Health experts advise that children receive the DTaP vaccine at ages two, four, six, and fifteen to eighteen months and again between the ages of four and six years. Adolescents and adults should then receive one administration of the Tdap vaccine, which contains less of the diphtheria and acellular pertussis components than the DTaP. After the Tdap, adults should receive the Td booster immunization against tetanus and diphtheria every ten years.
Impact
The DTaP vaccine has made a significant impact on public health by reducing the incidence of the diseases it prevents. Diphtheria has been nearly eradicated in the United States, and the occurrence of tetanus and pertussis has been greatly diminished. However, of the three diseases, pertussis continues to affect many adults and children in the United States, with morbidity and mortality rates rising among infants. Adolescents and adults who were fully vaccinated against pertussis often see their immunity decline, emphasizing the critical importance of receiving a booster vaccination. Adults who contract pertussis may only experience mild symptoms, but the danger lies in their ability to spread the infection to others, such as children and those with compromised immune systems. Furthermore, the anti-vaccine movement of the twenty-first century has put the work of vaccines in jeopardy.
Bibliography
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Loehr, Jamie. The Vaccine Answer Book: Two Hundred Essential Answers to Help You Make the Right Decisions for Your Child. Naperville, Ill.: Sourcebooks, 2010.
Ludlow, John T. "Diphtheria Tetanus Pertussis (DTaP) Vaccine - StatPearls." NCBI, 7 Oct. 2022, www.ncbi.nlm.nih.gov/books/NBK545173. Accessed 3 Oct. 2024.
Pan American Health Organization. World Health Organization. Control of Diphtheria, Pertussis, Tetanus, "Haemophilus influenzae" Type B, and Hepatitis B Field Guide. Washington, D.C.: Author, 2005.
Playfair, J. H. L., and B. M. Chain. Immunology at a Glance. 9th ed., Hoboken, N.J.: Wiley-Blackwell, 2009.
Plotkin, Stanley A., Walter A. Orenstein, and Paul A. Offit. Vaccines. 5th ed., Philadelphia: Saunders/Elsevier, 2008.