Diphtheria and Tetanus toxiod (DT)vaccine

The Diphtheria and Tetanus toxoid (DT)vaccine is a prescription medication belonging to the vaccine class.

The Diphtheria and Tetanus Toxoid (DT) vaccine is approved for immunising people against diphtheria and tetanus, two potentially fatal infections caused by Corynebacterium diphtheriae and Clostridium tetani.

It is a part of national routine immunization programmes in high-risk areas where the disease is prevalent.

The Diphtheria and Tetanus toxoid (DT) vaccine is given intramuscularly. It does not function according to standard pharmaceutical pharmacokinetics. Instead of passing through the normal absorption, distribution, metabolism, or elimination processes, it stimulates the immune system to produce antibodies to protect against diphtheria and tetanus.

The common side effects of the Diphtheria and Tetanus toxoid (DT)vaccine include pain, swelling, redness at the injection site, mild fever, irritability, and fatigue.

The Diphtheria and Tetanus toxoid (DT)vaccine is available as a suspension for injections.

The Diphtheria and Tetanus toxoid (DT)vaccine is available for travellers to at-risk areas in the United States, India, Brazil, Japan, Germany, Mexico and South Africa.

The Diphtheria and Tetanus toxoid (DT) vaccine belonging to the vaccine class is a sterile suspension solution. It protects against Diphtheria and Tetanus, particularly in children contraindicated to pertussis vaccination.

The lethal neurotoxin produced by Clostridium tetani causes tetanus, a rapidly progressing condition. The production of antibodies to neutralise the tetanus toxin is necessary for protection against the disease. The minimal protective threshold is defined as a serum antitoxin level of at least 0.01 IU/mL as determined by a neutralisation assay.

In contrast, diphtheria is an acute disease caused by Corynebacterium diphtheriae toxigenic strains of bacteria. By producing antibodies that are neutral to the toxin of Diphtheria, a defence against it is formed. Antitoxin concentrations of at least 0.1 IU/mL are typically regarded better as they provide increased protection, whereas serum antitoxin concentrations of 0.01 IU/mL give some protection. The DT vaccination protects individuals, especially children, against potentially fatal and life-threatening diseases.

The diphtheria and tetanus toxoid (DT) vaccines are available as injection suspensions.

Suspension for injection: To be administered parenterally, as applicable.

A healthcare professional administers the injectable DT vaccine. Typically, it is given in five doses during childhood, with a booster dose recommended every ten years for long-term protection after that.

The diphtheria and tetanus toxoid (DT) vaccines can be used as follows:

• Children receive the DT vaccination as part of their standard immunisation programmes to protect against diphtheria and tetanus's potentially fatal bacterial infections.
• DT vaccinations are administered as booster doses to maintain immunity in adults and adolescents.
• The DT vaccination can be administered to individuals who may not have previously received it as a prophylactic method during diphtheria outbreaks or in situations of possible tetanus exposure (such as wounds or injuries).

The diphtheria and tetanus toxoid (DT) vaccines can help support the following health benefits:

• Diphtheria prevention: DT vaccines effectively protect against diphtheria, a contagious bacterial infection caused by Corynebacterium diphtheriae. It primarily impacts the respiratory system and includes symptoms like fever, soreness in the throat, and breathing difficulty. In severe cases, death may occur. DT vaccinations boost. The immune system produces antibodies against the diphtheria toxin, avoiding infection and associated complications.
• Tetanus Prevention: The DT vaccination also helps in the prevention of tetanus, commonly referred to as "lockjaw," by promoting immunity against the tetanus toxin and providing protection against the bacterium Clostridium tetani, which causes tetanus, which affects the neurological system. Generally, people get it via infected wounds or traumas, and if tetanus is not treated, it can be fatal, leading to severe muscular rigidity and painful muscle spasms.
• Booster: Individuals receive booster doses of the DT vaccine every ten years to maintain protection after their initial completion of vaccines. Booster injections stimulate the immune response, ensuring protection against diphtheria and tetanus is adequate throughout their lifespan, maintaining a significant level of protection against certain bacterial diseases.
• Herd immunity: Public health benefits greatly from extensive DT vaccinations. The possibility for severe Diphtheria and Tetanus ramifications is reduced within the community. It protects the person vaccinated and those individuals with weaker immune systems, children, the elderly, and vulnerable populations, reducing the burden on healthcare systems and improving overall community wellbeing.

The Diphtheria and Tetanus toxoid (DT)vaccine is approved for its use in the following clinical indications:

• As a preventative measure against Diphtheria and Tetanus in children contraindicated to the pertussis vaccination.
• For active immunisation against diphtheria and tetanus in children up to the age of 7 years, DT is more beneficial than single-antigen tetanus toxoids.
• As a precautionary measure for individuals with reduced access to healthcare or at a higher risk of exposure to diphtheria and tetanus.
• For postexposure prophylaxis in individuals aged seven years who have yet to complete primary immunization, whose vaccination status is uncertain, or who have not had a diphtheria toxoid vaccine within five years.

Parenterally: The DT vaccine is given parenterally. The vaccine is injected into the anterolateral aspect of the thigh for infants under a year old, which may be used as a preferred injection site. In contrast, it is injected into the deltoid muscle for older and should not be injected in the gluteal area or areas where there may be a primary nerve trunk. It should only be administered intramuscularly and never IV, SC, or intradermally. When given concurrently with injectable vaccines, the shots have to be delivered using different syringes at different places. Following immunization, monitoring for at least 15 minutes for signs of any acute allergic reactions is essential.

The dosage and duration of treatment should be as per the treating physician's clinical judgment.

Suspension for injection: (2Lf/2Lf)/0.5mL (TDVAX)

(2Lf/5Lf)/0.5mL (Tenivac)

Where, Lf (flocculation units)

diphtheria/tetanus toxoid

Dosage Adjustment for Adult Patients

Initial Immunization

For adults who have not had their initial immunisation series, administer the first dose as Tdap, followed by the second dose as Td 0.5 mL IM at least four weeks later, and the third dose as Td 0.5 mL IM 6–12 months later.

Booster Immunization

Adults who completed their initial immunisation are routinely given a booster dose of 0.5 mL (Td or Tdap) every ten years.

The Diphtheria and Tetanus toxoid (DT)vaccine is available as a suspension for injection.

Diphtheria and Tetanus toxoid(DT)vaccine should be used to prevent Diphtheria and Tetanus toxoid (DT)virus infections in high-risk individuals, along with no appropriate nutritional restrictions.

JE vaccine usually has little effect on dietary or food substances when administered. Consuming regular foods and drinks before and after receiving the vaccine is safe.

Staying well hydrated by drinking water or other fluids is commonly advised. Maintaining a balanced diet that includes a variety of fruits, vegetables and lean proteins can help boost the body's immunological response to the vaccine and overall health during vaccination.

The dietary restriction should be individualized as per patient requirements.

Diphtheria and Tetanus toxoid (DT)vaccine may be contraindicated in the following conditions-

• Hypersensitivity (previous dose of toxoids or any of its components)
• Guillain-Barré syndrome
• Severe immunosuppressive conditions like HIV/AIDS or those receiving immunosuppressive medications
• Fever over 104°F (40°C)
• Allergic to latex rubber
• Arthus-type hypersensitivity reactions
• Seizure Disorder (for Pertussis-containing vaccines)
• History of systemic allergy or neurological responses to DT following a previous dose

The treating physician must closely monitor the patient and keep pharmacovigilance as follows.

• Children with weak immune systems, such as those with HIV/AIDS infection or cancer or who are taking certain drugs, may not respond as well to the DT vaccine and may consult a healthcare professional who might suggest modifying the vaccine schedule or giving additional doses to these people to improve protection.
• When delivering the vaccination, prompt access to treatment (including epinephrine 1:1000 for anaphylactoid/hypersensitivity responses) should be provided.
• If the individual has a moderately critical acute sickness (with or without fever), administration of the vaccine should be postponed.
• When administering intramuscular injections to individuals with thrombocytopenia or other clotting abnormalities, caution should be used.
• If an individual is receiving other vaccines simultaneously, healthcare providers should cautiously administer the vaccine, considering all the potential interactions and the intervals between vaccinations.
• It is recommended not to reconstitute or dilute the vaccine before administration.
• When booster doses of tetanus toxoid are administered to those who have already had their tetanus vaccination, there is an increased risk of local and systemic responses.

Caution is advised when consuming alcohol with the Diphtheria and Tetanus toxoid (DT)vaccine.

There is no sufficient scientific evidence regarding the use and safety of the Diphtheria and Tetanus toxoid (DT)vaccine in the breastfeeding population.

The adverse reactions related to the Diphtheria and Tetanus toxoid (DT)vaccine can be categorized as

• Common: Pain, swelling, redness at the injection site, headache, sore/ swollen joints and myalgia.
• Less common: Fever>104.9°F
• Rare: Severe Allergic Reactions (Anaphylaxis) and Syncope(primarily in adolescents)

Postmarketing Reports (Age 7 or older)

Disorders of the blood and lymphatic system/ lymphadenopathy

Immune system problems include allergic responses such as erythematous rash, maculopapular rash, urticaria, pruritus, and anaphylactic events such as bronchospasm and oedema.

Nervous system disorders: paresthesia, vertigo, syncope, and Guillain-Barre syndrome

Gastrointestinal disorders: Vomiting

Musculoskeletal, connective tissue and bone disorders: Myalgia and discomfort in the extremities

Conditions at the administration location and general disorders: injection site responses, such as swelling, pruritus, cellulitis, inflammation, mass, induration, warmth, and pain; tiredness and peripheral oedema.

The clinically relevant drug interactions of the Diphtheria and Tetanus toxoid (DT)vaccine are briefly summarized here:

• Immunosuppressants- The immunological response to Diphtheria and Tetanus toxoid (DT)vaccine may be suppressed by immunosuppressive treatments such as radiation, antimetabolites, alkylating agents, cytotoxic medicines, and corticosteroids (used in dosages larger than therapeutic doses).
• Other Vaccines- Multiple vaccinations, including the Diphtheria and Tetanus toxoid (DT)vaccine, given at the same time may increase the risk of adverse reactions. To reduce such a risk, medical professionals frequently adhere to vaccination regimens considering the time and space of vaccines.

The common side of the DT Vaccine includes the following-

• Irritability or fussiness
• Pain, redness or swelling where the shot was given
• Fatigue
• Feeling tired or weak.
• Joint pain or swelling.
• Upset stomach.
• Diarrhea.
• Mild fever.

The Diphtheria and Tetanus toxoid (DT) Vaccine should be prudent in the following population groups.

• Pregnancy: There is no sufficient scientific evidence traceable regarding the use and safety of the DT vaccine for pregnant populations.
• Paediatrics: The Diphtheria and Tetanus Toxoid (DT) vaccination is safe for children because it protects against diphtheria and tetanus, avoiding potentially severe and life-threatening diseases and maintaining children's long-term health and well-being.

Dosage Adjustment for Paediatric Patients

Initial Immunization

For individuals who have never received a vaccination

Less than seven years

5-dose series

If the pertussis component is contraindicated, DT may be administered; DTaP is suggested for the first immunisation of children under seven.

0.5 mL intramuscularly at 2, 4, and 6 months of age; this dosage can be given as early as six weeks and should be repeated every 4 to 8 weeks.

Fourth dose: If at least six months have passed since the third dose, it may be administered as early as 12 months of age.

If the fourth dose is administered to a child older than 4, the fifth dose can be avoided.

More than seven years

Unimmunized individuals

Administer the first dose as Tdap. THEN

At least four weeks following the first dosage, administer the second dose as Td 0.5 mL IM, and only then.

Provide the third dosage as Td 0.5 mL intramuscularly six months later.

Booster

Patients who completed their initial immunisation get 0.5 mL intramuscularly every ten years.

• Geriatrics: There is no sufficient scientific evidence traceable regarding the use and safety of the DT vaccine for geriatric populations.

• Lactating mothers: There is no sufficient scientific evidence traceable regarding the use and safety of the DT vaccine for lactating mother populations.

Dosage Adjustment in Kidney Impairment

There are no specific dosage adjustments provided.

Dosage Adjustment in Hepatic Impairment

There are no specific dosage adjustments provided.

Overdosage of the Diphtheria and Tetanus toxoid (DT) vaccine rarely occurs because healthcare professionals administer it according to specific or precise dosing guidelines.

There is no specific antidote or treatment for excessive intake of DT vaccine. Medical attention should be sought immediately when an overdose is suspected, followed by close monitoring for any adverse effects or allergic reactions. Supportive therapy may include epinephrine and antihistamines if there are signs of an allergic response, as needed, addressing any symptoms that persist or worsen. Physical treatment might be added if necessary.

Pharmacodynamics of Diphtheria and Tetanus toxoid (DT) vaccine:

The Diphtheria and Tetanus toxoid (DT)vaccine has a potential physiological mechanism that plays a role in its pharmacodynamics, involving its interaction with the immune system. Following administration, the vaccination induces the immune system to develop antibodies against the diphtheria and tetanus toxins. The body generates these antibodies as a defence mechanism against these bacterial toxins. The vaccination activates explicitly B lymphocytes, a specific type of white blood cells. B lymphocytes produce antibodies that can fight the toxins the relevant bacteria release. Additionally, immunological memory cells are produced, providing ongoing defence. The body uses its immune system to recognise and fight the microorganisms that cause those diseases to prevent or minimise the severity of diphtheria and tetanus after exposure.

Pharmacokinetics of Diphtheria and Tetanus toxoid (DT) vaccine:

The Diphtheria and Tetanus toxoid (DT) vaccine is given intramuscularly. It does not function according to standard pharmaceutical pharmacokinetics. Instead of passing through the normal absorption, distribution, metabolism, or elimination processes, it stimulates the immune system to produce antibodies to protect against diphtheria and tetanus.

• Desai, Shalini et al. “Use of tetanus-diphtheria (Td) vaccine in children 4-7 years of age: World Health Organization consultation of experts.” Vaccine vol. 38,21 (2020): 3800-3807. doi:10.1016/j.vaccine.2020.01.018
• Seung Beom Han, Jung-Woo Rhim, Hye Jo Shin, Sang Yong Kim, Jong-Hyun Kim, Hyun-Hee Kim, Kyung-Yil Lee, Hwang Min Kim, Young Youn Choi, Sang Hyuk Ma, Chun Soo Kim, Dong Ho Kim, Dong Ho Ahn, Jin Han Kang,
• Immunogenicity and safety of the new reduced-dose tetanus–diphtheria vaccine in healthy Korean adolescents: A comparative active control, double-blind, randomized, multicenter phase III study,Journal of Microbiology, Immunology and Infection,Volume 50, Issue 2,2017,Pages 207-213,ISSN 1684-1182,https://doi.org/10.1016/j.jmii.2015.04.005.

• Inform the caregivers of the dosage and schedule for the vaccine, including the initial doses and booster shots. Typically, children receive a series of DT doses during infancy and childhood, followed by booster shots at specific intervals.
• Inform the vaccination recipient, their parents, or their guardians whether they had any side effects from a prior dosage of the DT vaccine and also the benefits of vaccination, such as preventing life-threatening diseases.
• Assure caregivers that DT immunizations are generally safe, with only minor, short side effects. Encouraging them to immediately report any unexpected or severe responses to the healthcare physician and, whenever applicable, to use reporting systems like the Vaccine Adverse Event Reporting System (VAERS)
• Inform caregivers of the recommended immunization schedule, which usually consists of two or three doses, depending on the vaccine brand used. Also, mention the ages at which the doses should be administered and give the Vaccine Information Statements, which must be disclosed before immunization by the National Childhood Vaccine Injury Act of 1986 about the Centers for Disease Control and Prevention (CDC) website (www.cdc.gov/vaccines), these resources are freely accessible.

https://www.pediatriconcall.com/drugs/dt-vaccine/525

https://main.mohfw.gov.in/sites/default/files/Universal.pdf

https://www.cdc.gov/vaccines/hcp/vis/vis-statements/td.html

https://www.indianpediatrics.net/oct2014/785 figure1.pdf

https://www.ncbi.nlm.nih.gov/books/NBK236292/