
DTaP and Tdap are vaccines to protect against diphtheria, tetanus, and pertussis also known as whooping cough. These vaccines are effective in offering immunity to the vaccinated against the bacterial infections that and respiratory infection. The conditions are highly contagious in nature and can result in serious complications if infected. One of the condition, tetanus is also life threatening in nature. Following subsections offer a detailed look at the vaccines, including information that answers the question – DTaP vs Tdap Vaccines – What’s the difference between them?
Overview of conditions prevented by the DTaP vaccine
Acronym for Diphtheria, Tetanus, and acellular Pertussis vaccine, DTaP is given to infants and young children to provide immunity against the three diseases, listed below. DTaP vaccines are typically administered in a series of five doses given at specific intervals during childhood, usually at 2, 4, 6, and 15-18 months of age, with a booster dose given between 4-6 years of age.
Diphtheria, a bacterial infection that primarily affects the throat and can lead to severe breathing difficulties and heart problems.
- Tetanus, caused by a bacterium that produces a toxin affecting the nervous system. It can lead to muscle stiffness, lockjaw, and potentially life-threatening complications.
- Pertussis, or whooping cough, is a highly contagious respiratory infection characterized by severe coughing spells. It can be particularly dangerous for infants and young children.
Overview of conditions prevented by the Tdap vaccine
Acronym for Tetanus, diphtheria, and acellular Pertussis, the Tdap vaccine is a booster vaccine that provides continued protection against the three diseases mentioned below in older children, adolescents, and adults. Tdap is commonly recommended for adolescents between 11-12 years of age, as well as adults who have not received a previous Tdap vaccine. It is also advised during pregnancy to help protect newborns from pertussis. In some cases, a Td vaccine (tetanus and diphtheria) may be given instead of Tdap if pertussis immunity is not required.
- The Tdap vaccine contains additional components to boost immunity against tetanus and diphtheria. It helps maintain protection against these diseases beyond the childhood DTaP doses.
- The acellular pertussis component in Tdap helps prevent whooping cough.
Mechanism of action of DTaP Vaccines
The mechanism of action of DTaP vaccines involves stimulating the immune system to produce an immune response against the bacteria that cause diphtheria, tetanus, and pertussis. Each component of the vaccine works as outlined below:
- Diphtheria Toxoid: The DTaP vaccine contains inactivated diphtheria toxin, also known as a toxoid. The toxoid is derived from the toxin produced by the bacteria Corynebacterium diphtheriae, which causes diphtheria. The toxoid is treated to remove its toxicity while retaining its ability to stimulate an immune response. When the vaccine is administered, the immune system recognizes the toxoid as a foreign substance and produces antibodies against it. These antibodies help neutralize the diphtheria toxin if a person is exposed to the actual diphtheria bacteria.
- Tetanus Toxoid: Similar to diphtheria toxoid, the DTaP vaccine includes an inactivated form of the toxin produced by the bacterium Clostridium tetani, which causes tetanus. The toxoid stimulates the production of antibodies against the tetanus toxin. In the event of an actual tetanus infection, these antibodies can bind to and neutralize the toxin, preventing it from causing the characteristic muscle stiffness and spasms associated with tetanus.
- Acellular Pertussis Components: The pertussis component of the DTaP vaccine contains inactivated components of the Bordetella pertussis bacteria. Unlike older whole-cell pertussis vaccines, which used whole, killed bacteria, the acellular pertussis vaccines use purified components of the bacteria. These components typically include pertussis toxin, filamentous hemagglutinin, pertactin, and fimbriae. These components stimulate the production of antibodies against pertussis bacteria, helping to prevent or lessen the severity of the infection.
By introducing these inactivated components of the disease-causing bacteria into the body, the DTaP vaccine triggers the immune system to recognize and respond to these bacteria. When vaccinated individuals are exposed to the actual bacteria in the future, the immune system mounts a rapid and effective immune response, preventing or reducing the severity of the infection.
The immune response generated by the DTaP vaccine provides long-lasting protection against diphtheria, tetanus, and pertussis. However, immunity can reduce over time, and booster doses of Tdap or Td vaccines are recommended in adolescence and adulthood to maintain protection against these diseases.
Possible side effects of DTaP Vaccines and precautions
All medications, including vaccines come with the possibility of undesirable effects and DTaP vaccines are no exception, despite being considered as generally safe and well-tolerated. The most common side effects of DTaP vaccines include the following:
#1 Mild reactions at the injection site:
Redness, swelling, or soreness at the site where the vaccine is administered. These local reactions are usually mild and resolve on their own within a few days.
#2 Fever:
A low-grade fever is a relatively common side effect after DTaP vaccination. It typically occurs within the first 24-48 hours and is usually mild and short-lived.
#3 Irritability or fussiness:
Some children may experience increased irritability or fussiness following DTaP vaccination. This is usually temporary and resolves within a day or two.
#4 Fatigue or drowsiness:
Some individuals may feel tired or sleepy after receiving the vaccine. This side effect is generally mild and temporary.
Serious side effects from DTaP vaccines are rare, but can occur. This includes severe allergic reactions such as anaphylaxis, seizures, or high fever – above 105°F. The risk of serious side effects is much lower than the risks associated with contracting the actual diseases prevented by the vaccine.
Precautions and considerations regarding DTaP vaccines include:
- Allergies: Individuals with known severe allergic reaction to a previous dose of DTaP or any vaccine component are not to receive further doses. Any history of severe allergic reactions to a specific vaccine component, such as neomycin or any other vaccine ingredient, needs to be informed to the healthcare providers.
- Fever management: Whenever fever develops after vaccination, over-the-counter pain relievers such as acetaminophen or ibuprofen is typically used to help manage discomfort. However, aspirin should not be given to children or adolescents due to the risk of a rare but serious condition called Reye’s syndrome.
It’s important to consult with healthcare professionals for personalized advice and to discuss any specific concerns or medical conditions before receiving the DTaP vaccine.
Mechanism of action of Tdap Vaccines
The mechanism of action of Tdap vaccines is similar to that of DTaP vaccines, as both provide protection against diphtheria, tetanus, and pertussis. Tdap vaccines stimulate the immune system to produce an immune response against the respective bacteria and their toxins. Here’s a breakdown of how each component of the Tdap vaccine works:
Tetanus Toxoid: The Tdap vaccine includes an inactivated form of the tetanus toxin, derived from the bacterium Clostridium tetani. The tetanus toxoid stimulates the production of antibodies that specifically target the tetanus toxin. These antibodies can neutralize the toxin if a person is exposed to the actual tetanus bacteria, preventing the development of tetanus symptoms.
Diphtheria Toxoid: Similar to the DTaP vaccine, Tdap vaccines contain an inactivated form of the diphtheria toxin, produced by the bacterium Corynebacterium diphtheriae. The diphtheria toxoid triggers the production of antibodies against the diphtheria toxin. These antibodies can neutralize the toxin and prevent it from causing severe respiratory and heart complications associated with diphtheria.
Acellular Pertussis Components: The pertussis component in Tdap vaccines consists of inactivated components of the Bordetella pertussis bacteria, similar to the DTaP vaccine. These components typically include pertussis toxin, filamentous hemagglutinin, pertactin, and fimbriae. When the vaccine is administered, these components stimulate the immune system to produce antibodies against pertussis bacteria. These antibodies can help prevent or reduce the severity of pertussis infection if a person is exposed to the actual bacteria.
By introducing these inactivated components of the disease-causing bacteria, the Tdap vaccine primes the immune system to recognize and respond to the bacteria and their toxins. Resultantly, the immune system mounts a swift and effective immune response, providing protection against diphtheria, tetanus, and pertussis whenever a vaccinated individual is exposed to the actual bacteria in the future.
Side effects of Tdap Vaccines and precautions
Tdap vaccines are also regarded as generally safe and well-tolerated, but like all other vaccines, the possibility of side effects exists. The most common side effects of Tdap vaccines include:
#1 Local reactions at the injection site:
This includes possible redness, swelling, or soreness at the site where the vaccine was administered. These local reactions are typically mild and temporary, resolving on their own within a few days.
#2 Fever:
A low-grade fever is a common side effect after Tdap vaccination. It usually occurs within the first 24-48 hours and is generally mild and short-lived.
#3 Fatigue or drowsiness:
Some individuals may experience tiredness or sleepiness after receiving the vaccine. This side effect is generally mild and temporary.
#4 Headache:
Headaches can occur as a side effect, but they are typically mild and resolve on their own.
Serious side effects from Tdap vaccines are rare, but may occur. These are similar to that of DTaP vaccines and include severe allergic reactions such as, seizures, or high fever – above 105°F.
Precautions and considerations regarding Tdap vaccines include:
- Allergies: Individuals with a known severe allergic reaction to a previous dose of Tdap or any vaccine component are not to receive further doses.
- Guillain-Barré Syndrome: In rare cases, a small increased risk of Guillain-Barré Syndrome, a rare neurological disorder, has been associated with Tdap vaccines. The risk is estimated to be less than one in a million doses. Individuals are to inform healthcare providers of any prior history of GBS before vaccination.
- Fever management: If a fever develops after vaccination, aspirin should not be given to children or adolescents due to the risk of Reye’s syndrome.
DTaP vs Tdap Vaccines – What’s the difference between them?
It is now time to answer the above question. As can be seen from the information above, DTaP and Tdap vaccines are similar in terms of the diseases protected. For instance, both vaccines offer immunity against diphtheria, tetanus, and pertussis. However, there is a difference – they differ in their target populations and dosages. Here is a look at the main differences between DTaP and Tdap vaccines:
Target Population:
DTaP vaccines are primarily administered to infants and young children as part of their routine vaccination schedule. They are given in a series of doses during early childhood to provide immunity against diphtheria, tetanus, and pertussis.
Tdap vaccines are intended for older children, adolescents, and adults. They serve as booster doses to maintain or enhance the immunity acquired from childhood DTaP vaccines and provide continued protection against diphtheria, tetanus, and pertussis.
Pertussis Component:
The pertussis component in DTaP vaccines contains an acellular pertussis vaccine, which means it contains purified and inactivated components of the Bordetella pertussis bacteria. The acellular pertussis vaccine helps prevent pertussis and is considered safer with fewer side effects.
Tdap vaccines also contain an acellular pertussis component, similar to DTaP. However, the pertussis component in Tdap vaccines may have different antigen compositions and may be formulated to elicit a stronger immune response in older individuals.
Dosage:
DTaP vaccines are typically administered as a series of five doses during early childhood. The first three doses are typically given at 2, 4, and 6 months of age, followed by a fourth dose between 15-18 months, and a fifth dose between 4-6 years of age.
Tdap vaccines are typically administered as a single booster dose. It is generally recommended for adolescents between 11-12 years of age to replace the routine DTaP vaccine dose given at 4-6 years. Additionally, Tdap boosters are recommended for adults who have not previously received a Tdap vaccine, especially during pregnancy to protect newborns from pertussis.
The specific recommendations for DTaP and Tdap vaccines may vary based on country-specific immunization schedules and guidelines. The above information is intended to serve as a broad reference and does not substitute specialist medical advice. Individuals are advised to consult healthcare professionals for personalized advice and to follow recommended vaccination schedule for optimal protection against these diseases.