DTAP VACCINE

The acellular pertussis component (aP) of the DTaP vaccine is admin- istered to protect against pertussis (whooping cough), a potentially life-threatening bacterial disease, especially for infants under one year of age. Pertussis causes severe coughing fits that can make it difficult for children to breathe properly. These coughing fits, called coughing paroxysms can be so intense that they cause the child to lose their breath and produce a loud inspiratory “whoop” sound when they struggle to inhale, giving the disease its nickname. This process can result in cyanosis, where the child’s face turns blue due to a temporary lack of oxygen due to the coughing fits. 

A video depicting an infant girl with pertussis can be viewed at [this link]: https://www.youtube.com/watch?v=S3oZrMGDMMw

Although it is difficult to watch, this video is important because it vividly illustrates the severity of pertussis in young children. In recent times, complacency regarding severe diseases like pertussis has become more common. Many in our country have forgotten why vaccines are essential and why they were developed in the first place. Vaccines prevent severe disease and death. This video underscores this fact. For more information on addressing vaccine hesitancy, please see the section below on the subject.

The severity of pertussis varies with age, affecting different age groups in distinct ways. Infants with pertussis often require intensive care and prolonged hospitalization due to the severe nature of the infection at this age. In older children, the infection is less severe but still results in a persistent, severe cough. Recently, pertussis has become more common among teenagers and young adults, who may experience a persistent cough lasting longer than three weeks. Despite the lower severity in older age groups, the prolonged cough can significantly impact daily activities and quality of life. Universal immunization through scheduled vaccinations is the most effective way to prevent pertussis infections across all age groups.

Pregnant women are recommended to receive a Tdap vaccine during the third trimester of each pregnancy. This vaccination strategy not only protects the mother from pertussis (also known as whooping cough) but also helps transfer protective antibodies to the baby. These antibodies can significantly reduce the risk of the newborn contracting pertussis during the first few months of life, when they are most vulnerable and unable to receive their own vaccinations. The Tdap vaccine is an important preventive measure to safeguard both maternal and infant health and is a key component in the effort to minimize the incidence of pertussis in newborns.

To prevent pertussis in babies, a primary series of DTaP vaccinations for babies begins at two months of age and consists of three doses given at two-month intervals. Additional booster doses are administered in early childhood at 15 months and again at 4 years of age (the preschool shots), totaling five doses. Delaying doses of the DTaP is most unwise because it opens up a window of opportunity for disease to strike babies.

With each successive dose of the five needed doses, additional and more permanent immunity is added:

First Dose: After the initial dose, some immunity begins to develop. However, the protection against pertussis (whooping cough) is not strong at this point. Immunity against diphtheria and tetanus starts to form but is relatively low compared to the complete series. In other words, the child is not completely protected with the first dose to all three components.

Second Dose: The second dose boosts the immune response. For pertussis, the protection is better, but full protection still requires additional doses.

Third Dose:  After the third dose, the vaccine usually provides about 80- 85% protection against pertussis. Immunity against diphtheria and tetanus also strengthens considerably as well.

Fourth Dose: This dose further boosts immunity. The pertussis protection 147 increases to about 80-90%. This is considered the baseline for pertussis immunity. Other vaccines offer much higher levels of protection than the pertussis vaccine.

Fifth Dose: The final dose in the series is typically given around 4-6 years of age, ensuring long-lasting immunity into the school years. It helps maintain the protection levels of around 80-90% for pertussis and also solidifies high long-term protection against the other two diseases in the vaccine: diphtheria and tetanus.

It’s important to note that immunity to pertussis can decrease over time, which is why booster doses of the Tdap vaccine are recommended during adolescence and into adulthood. Implementing universal immunization programs helps establish herd immunity, which is crucial in pre- venting the spread of communicable diseases like pertussis. By reducing the number of individuals who can carry the disease, the overall exposure within the population decreases. This limits the transmission and perpetuation of the disease. Herd immunity is a compelling reason to support universal immunization programs and practices.

In summary, given the significant risks and potential severity of pertussis, comprehensive vaccination programs are essential. These include maternal immunization during pregnancy and ensuring that infants receive their primary series of vaccinations on schedule. Such measures are critical in combating the disease and protecting vulnerable populations, especially newborns and those who cannot be vaccinated due to medical reasons.

Adverse Reactions to the DTaP Immunization: Potential minor side effects of DTaP vaccine may occur in a few of the children receiving it. These reactions are not concerning. They usually resolve in 24 to 48 hours after receiving the immunization. These reactions may include:

1. Fever, usually around 101 degrees F. You may treat this with acetaminophen (see dosing Guide).
2. Irritability and fussiness. Your child should be consolable and not have uncontrollable crying. See below on when to call if this is excessive.
3. Redness, swelling and/or knot at the injection site. The redness and swelling will resolve within a few days. Sometimes the knot at the injection site may persist for weeks to months. This should be of no concern.

A message to Grandparents:  The transition from the whole-cell pertussis vaccine (DTP) used in previous generations of children in the US, to the newer acellular pertussis vaccine (DTaP) that we now use was driven by the need to reduce side effects of the vaccine. The newer DTaP vaccine, which includes acellular pertussis vaccine, was licensed in the US in 1991 for the fourth and fifth booster doses and later received approval for the entire series in 1996, replacing the whole-cell version in routine immunization programs. 

The whole-cell version of the Diphtheria Tetanus Pertussis vaccine, introduced in 1948, contained inactivated whole cells of Bordetella pertussis bacteria. While this vaccine provided effective protection against pertussis, it often caused significant side effects, such as fever, pain at the injection site, and, in some cases, severe reactions. It was a crude vaccine composed of the entire inactivated Bordetella pertussis bacterium, which contains several cell proteins that can be toxic to children. As a result, reactions to the old DTP vaccine occurred relatively frequently.

By 1991, advancements in vaccine technology led to the development and approval of the acellular pertussis vaccine that is widely used today. Unlike the older whole-cell DTP version, the acellular DTaP vaccine contains purified protein components from the pertussis bacterium’s outer cell coat. The cell coat proteins of the DTaP vaccine effectively trigger a protective immune response but are free from the other toxic proteins that were present in the whole-cell vaccine. The newer acellular pertussis vaccine is produced through recombinant DNA technology. These purified components make the DTaP vaccine both effective and significantly safer, resulting in fewer and milder side effects.

The introduction of the newer DTaP vaccine marked a significant improvement in the balance between efficacy (effectiveness) and tolerability. The DTaP vaccine is highly effective at preventing pertussis and has minimal side effects. Grandparents who remember the more intense reactions of the past can rest assured that today’s DTaP vaccine offers improved safety with effective disease prevention.

In summary, Pertussis still occurs every year in Arkansas and has increased in the last few years. In our practice, we treat children with pertussis with some frequency. Many children who catch pertussis are inadequately immunized. If your child remains un-immunized to pertussis, you are taking a great risk with his or her health. Pertussis immunizations have prevented the devastating pertussis epidemics of the past. We agree with the ACIP and the American Academy of Pediatrics in recommending that your child receive diphtheria, tetanus and acellular pertussis vaccines unless specifically advised against by our office, which is extremely rare.

The D component of the DTP immunization prevents diphtheria, a serious disease which can cause difficulty breathing due to a pus-filled pseudomembrane in the throat, paralysis and even heart failure. 5 to 10% of the people who get diphtheria die of it. The Diphtheria component of the vaccine is quite safe with few side effects.

The T component of the DTP immunization prevents tetanus (lock- jaw). Please see the section below on tetanus.