Tetanus

What

Tetanus is caused by a bacterium found in soil. The bacteria can enter wounds and produce a neurotoxin that acts on the central nervous system to cause muscle rigidity with painful spasms. Tetanus-toxoid vaccines prevent disease by making antibodies that bind to the toxin, rather than the bacteria.

Who

Tetanus-toxoid vaccine is recommended for:

• routine vaccination in infants, children and adolescents
• routine booster vaccination in adults, including travellers to countries where health services are difficult to access
• post-exposure prophylaxis in people with a tetanus-prone wound
• vaccination of people who have missed doses of tetanus-toxoid vaccine

How

Tetanus-toxoid vaccines are only available in Australia as combination vaccines that include other antigens such as pertussis and diphtheria.

Tetanus-toxoid vaccines are recommended for children at 2, 4, 6 and 18 months, and 4 years of age, and adolescents at 11–13 years of age.

A tetanus-toxoid vaccine booster is recommended for all adults at 50 years of age and at 65 years of age if it is more than 10 years since the last dose.

Vaccination is recommended every 10 years for travellers to countries where health services are difficult to access. Travellers with a higher risk of a tetanus-prone wound are recommended to be vaccinated every 5 years.

The need for tetanus-toxoid vaccine in people with a tetanus-prone wound, with or without tetanus immunoglobulin, depends on the nature of the wound and the person’s vaccination history.

Adolescents and adults who have never had a tetanus-toxoid vaccine are recommended to receive 3 doses of tetanus-toxoid vaccine with at least 4 weeks between doses, and booster doses at 10 years and 20 years after the primary course.

Why

Tetanus is rare in Australia because of high vaccination coverage. It occurs in people of any age, but mainly in older adults who have never been vaccinated or were vaccinated more than 10 years ago. The case-fatality rate in Australia is about 2%. Whilst rare, tetanus can be severe, potentially requiring sedation or prolonged ventilation in intensive care.

Tetanus vaccines available in Australia

The Therapeutic Goods Administration website provides product information for each vaccine.

See also Vaccine information and Variations from product information for more details.

Dose and route

The dose of all tetanus-toxoid vaccines is 0.5 mL given by intramuscular injection.

Co-administration with other vaccines

Do not mix DTPa- or dTpa-containing vaccines or dT vaccine with any other vaccine in the same syringe, unless specifically registered for use in this way.

Tetanus-toxoid vaccines can be co-administered with most other vaccines.

Vaxelis can be given at the same time as other scheduled vaccines, including MenB vaccines.

Nimenrix vaccine contains small amounts of tetanus toxoid. If a person needs to receive Nimenrix and a vaccine containing tetanus toxoid, co-administration of these vaccines is preferred. Giving Nimenrix after a vaccine containing tetanus toxoid may interfere with the immune response against some meningococcal serogroups. There is uncertainty about whether this reduced immune response affects clinical protection, and there are no data on the optimal interval between the vaccines. Therefore, Nimenrix should be given as scheduled, even if it is being given shortly after a vaccine containing tetanus toxoid.

Interchangeability of tetanus vaccines

If possible, complete the vaccination schedule for tetanus with the same vaccine brand. If this is not possible, use an alternative brand of the same antigen combination following the dose recommendations. See Recommendations.

People who have clinical tetanus should receive tetanus immunoglobulin for intravenous use.¹²

The recommended dose is 4000 IU, to be given by slow intravenous infusion. Consult detailed protocols on using this product and managing adverse events.

The Australian Red Cross Blood Service has information about tetanus immunoglobulin:

• for intramuscular use to manage tetanus-prone wounds
• for intravenous use to treat clinical tetanus

See Public health management for more details.

Contraindications

The only absolute contraindications to tetanus-toxoid vaccines are:

• anaphylaxis after a previous dose of any tetanus-toxoid vaccine
• anaphylaxis after any component of a tetanus-toxoid vaccine

If a person has a tetanus-prone wound and has previously had a severe adverse event after tetanus vaccination, consider other measures, including using tetanus immunoglobulin.

Precautions

People with latex allergy

The product information for Adacel states that the tip cap of the syringe contains latex. Consider using an alternative product in people with an allergy or sensitivity to latex.

Mild discomfort or pain at the injection site is common after receiving a tetanus-toxoid vaccine. This can last for a few days. Uncommon general adverse events after receiving dT vaccine include:

• headache
• lethargy
• malaise
• myalgia
• fever

Very rare adverse events after receiving dT vaccine include:

• anaphylaxis
• urticaria
• peripheral neuropathy

Brachial neuritis may occur after receiving tetanus-toxoid vaccine. This is inflammation of a nerve in the arm, causing weakness or numbness. The estimated excess risk is approximately 0.5–1 in 100,000 doses in adults.^{13, 14}

Specific adverse events after receiving a combination vaccine containing both tetanus and pertussis antigens are extensive limb swelling, febrile convulsions and hypotonic-hyporesponsive episodes. See Pertussis for more details.

Combination vaccines containing both tetanus and pertussis antigens are safe and well tolerated in adults when given as a booster dose.^3,15-17 See Pertussis.

Local and systemic adverse reactions are more common after hexavalent vaccines than after monovalent vaccines. There is little to no difference in the rates of adverse events after hexavalent vaccines compared with other combination vaccines including other hexavalent vaccines.^18-20

Adverse reactions to a single dose of dTpa vaccine are similar whether a person receives the vaccine shortly after, or at a longer interval after, a previous dT vaccine.^21-24 (See also Pertussis).

Tetanus is caused by the bacterium Clostridium tetani. C. tetani is a motile, non-capsulated, gram-positive rod that forms endospores. Spores are found in manured soil and can enter wounds. Once in a wound, the bacteria can grow anaerobically.^1,25

C. tetani produces a potent protein toxin that has 2 components:

• tetanospasmin, a neurotoxin
• tetanolysin, a haemolysin

These toxins cause the symptoms of tetanus.

The incubation period is often 3–21 days. This can range from 1 day to several months. The median onset is 10 days after injury.

Generally, a shorter incubation period is associated with:

• a more heavily contaminated wound
• more severe disease
• a worse prognosis

Tetanus is an acute disease and can be fatal. The neurotoxin acts on the central nervous system to cause muscle rigidity with painful spasms.^1,25

Symptoms of tetanus

Generalised tetanus is the most common form of the disease. It is characterised by increased muscle tone and generalised spasms.

Early symptoms and signs of tetanus include:

• increased tone in the masseter muscles (trismus, or lockjaw)
• dysphagia
• stiffness or pain in the neck, shoulder and back muscles

Some patients develop generalised muscle spasms that are paroxysmal, violent and painful. During generalised spasms, the person may have reduced ventilation, apnoea or laryngospasm.

The person may be febrile, although many have no fever.

The mental state is unimpaired.

Sudden cardiac arrest sometimes occurs, but its basis is unknown.

Complications and death from tetanus

Other complications include:

• pneumonia
• fractures
• muscle rupture
• deep vein thrombophlebitis
• pulmonary emboli
• decubitus ulcers
• rhabdomyolysis

Death can result from:

• respiratory failure
• hypertension
• hypotension
• cardiac arrhythmia

Tetanus can occur after apparently trivial wounds, or even unnoticed wounds. The amount of tetanus toxin required to produce clinical symptoms is too small to induce a protective antibody response. Unimmunised people have been known to have tetanus more than once.

For these reasons, active immunisation is required.²⁶ A completed course of vaccination protects against tetanus for many years.

Tetanus in Australia

Tetanus remains rare in Australia and the number of annual notifications has remained stable since 2005. It occurs at any age, but in Australia, is mainly seen in adults who have never been vaccinated or were vaccinated more than 10 years ago.

Between 2016 and 2018, 14 cases of tetanus were notified in Australia (average annual rate of 0.02 per 100,000 population) and 52 hospitalisations (average annual hospitalisation rate 0.07 per 100,000 population) were reported.²⁷ This difference in numbers between notifications and hospitalisations suggests that tetanus is under-notified in Australia. 

Between 2016 and 2018, the majority of reported tetanus cases were in adults aged 25–49. This age group also had the highest proportion of hospitalisations (21/52; 40%) followed by people aged 15–24 years (13/52; 25%).27 The case-fatality rate in Australia is about 2%.²⁸

 

Prevalence in immunised people

Tetanus is rare in:

• people who have received 4 or more doses of a tetanus-toxoid vaccine
• people who had a dose of a tetanus-toxoid vaccine within the past 10 years ^26,29

However, cases in immunised people have been reported.^30,31

Clinicians in industrialised countries, including Australia, should consider tetanus when there are appropriate symptoms and signs. Tetanus should be considered whether the person has been vaccinated or not. This is especially true for older people. Most tetanus-related deaths are in people >70 years of age, especially women. Death may be associated with tetanus occurring after a seemingly minor injury.^26,29,32

Tetanus toxoid is available in Australia only in combination with diphtheria toxoid. Vaccines may also include other antigens, such as pertussis, inactivated poliovirus, hepatitis B and Haemophilus influenzae type b.

The acronym DTPa, using capital letters, signifies a child formulation of diphtheria, tetanus and acellular pertussis–containing vaccine.

The acronym dTpa signifies a formulation that contains substantially less diphtheria toxoid and pertussis antigens than the child formulation. Adolescents and adults are recommended to receive dTpa vaccine.

Immunogenicity

Tetanus vaccination stimulates the production of antibodies, also known as ‘antitoxin’. This means that vaccination does not stop Clostridium tetani growing in contaminated wounds, but it does protect against the effects of the toxin.

The vaccine antigen is prepared by treating a cell-free toxin preparation with formaldehyde. This converts it into tetanus toxoid, which is safe.

Tetanus toxoid is usually adsorbed onto an adjuvant to increase its immunogenicity. Adjuvants are either aluminium phosphate or aluminium hydroxide. Antigens from Bordetella pertussis also act as an effective adjuvant in combination vaccines.

The circulating level of antitoxin needed for protection from tetanus is 0.1– 0.2 IU per mL.³³

Studies have shown that, 1 month after the 3-dose primary vaccination series of DTPa, 97.4–100% of infants had tetanus antitoxin levels ≥0.1 IU per mL. Following a 4th dose in the 2nd year of life, 96.8–100% of infants had antibody titres of ≥0.1 IU per mL for both tetanus and diphtheria. ^34,35

A study of adults with unknown vaccination history showed that, after 3 doses of either a dT or a dTpa vaccine, 99% had protective antibody levels.³

Clinical trials showed that after 3 doses of a hexavalent vaccine, 99.6–100% of infants had antibody levels ≥0.1 IU per mL.^36,37

Duration of immunity

A complete immunisation schedule induces protective levels of antitoxin throughout childhood and into adulthood. But, by middle age, about 50% of vaccinated people have low or undetectable levels of antitoxin.^2,38,39 A single dose of tetanus vaccine produces protective levels of antitoxin in these people.^40-43

Transport according to National vaccine storage guidelines: Strive for 5.⁴⁴ Store at +2°C to +8°C. Do not freeze. Protect from light.

Infanrix hexa vaccine must be reconstituted. Add the entire contents of the syringe to the vial and shake until the pellet completely dissolves. Use the reconstituted vaccine as soon as practicable. If it must be stored, hold at room temperature for no more than 8 hours.

Tetanus is a notifiable disease in all states and territories in Australia.

State and territory public health authorities can provide advice about the public health management of tetanus, including management of cases. See People who have a tetanus-prone wound and Table. Guide to tetanus prophylaxis in wound management for details on managing tetanus-prone wounds. Contact the Australian Red Cross Blood Service to access tetanus immunoglobulin:

• for intramuscular use to manage tetanus-prone wounds
• for intravenous use to treat clinical tetanus

Routine vaccination in children and adults

Infanrix

The product information for Infanrix states that this vaccine is for:

• primary immunisation of infants aged between 2 months and 12 months
• booster dose in children aged 15 months to 6 years who have previously been vaccinated against diphtheria, tetanus and pertussis

The Australian Technical Advisory Group on Immunisation (ATAGI) recommends that Infanrix may also be used for catch-up of the primary schedule or as a booster in children <10 years of age. ATAGI also recommends that the primary schedule can start at 6 weeks of age.

Infanrix hexa

The product information for Infanrix hexa states that this vaccine is for:

• primary immunisation of infants from the age of 6 weeks
• booster dose in children 18 months of age if they need boosting for all antigens

ATAGI recommends that Infanrix hexa may also be used for catch-up of the primary schedule or as a booster in children <10 years of age.

Vaxelis

The product information for Vaxelis states that this vaccine is for:

• primary immunisation of infants from the age of 6 weeks
• a booster dose at least 6 months after the last priming dose

ATAGI recommends that Vaxelis may also be used for catch-up of the primary schedule or as a booster in children <10 years of age.

Infanrix IPV

The product information for Infanrix IPV states that this vaccine is for:

• use in a 3-dose primary schedule for immunisation of infants from the age of 6 weeks
• a single booster dose in children ≤6 years of age who have previously been vaccinated against diphtheria, tetanus, pertussis and poliomyelitis

ATAGI recommends that Infanrix IPV may also be used for catch-up of the primary schedule or as a booster in children <10 years of age.

Quadracel

The product information for Quadracel states that this vaccine is for:

• use in a 3-dose primary schedule from the age of 2 months to 12 months
• booster dose in children from 15 months to 6 years of age who have previously been vaccinated against diphtheria, tetanus, pertussis and poliomyelitis

ATAGI recommends that Quadracel may also be used for catch-up of the primary schedule or as a booster in children aged <10 years. ATAGI also recommends that the primary schedule can start at 6 weeks of age.

Tripacel

The product information for Tripacel states that this vaccine is for:

• use in a 3-dose primary schedule from the age of 2 months to 12 months
• booster dose in children from 15 months to 8 years of age who have previously been vaccinated against diphtheria, tetanus and pertussis

ATAGI recommends that Tripacel may also be used for catch-up of the primary schedule or as a booster in children aged <10 years. ATAGI also recommends that the primary schedule can start at 6 weeks of age.

Adacel and Boostrix

The product information for Adacel (reduced antigen content dTpa) states that this vaccine is for use in people aged ≥10 years for booster doses only.

The product information for Boostrix (reduced antigen content dTpa) states that this vaccine is for use in people aged ≥4 years for booster doses only.

ATAGI recommends that, when an adolescent or adult receives a 3-dose primary course of diphtheria/tetanus toxoids:

• dTpa should replace the 1st dose of dT
• the 2nd and 3rd doses should be dT

If dT is not available, dTpa can be used for all 3 primary doses.

The product information for Adacel and Boostrix states that there is no recommendation about the frequency of vaccination against pertussis in adults. ATAGI recommends that adults in contact with infants and/or at increased risk from pertussis should have received a vaccine within the past 10 years.

ADT Booster

The product information for ADT Booster states that this vaccine is for use as a booster dose only in:

• children aged ≥5 years
• adults who have previously received at least 3 doses of diphtheria and tetanus vaccines

ATAGI recommends that, where a dT vaccine is required, ADT Booster can be used for any dose. This includes for primary immunisation against diphtheria and tetanus for any person ≥10 years of age.

Adacel Polio, Boostrix and Boostrix-IPV

The product information for Adacel Polio, Boostrix and Boostrix-IPV states that vaccine is for use in people aged ≥4 years for booster doses only.

ATAGI recommends that Adacel Polio, Boostrix and Boostrix-IPV should not be used in people aged <10 years, except in certain circumstances.

Vaccination during pregnancy

The product information for Adacel states that vaccinating pregnant women is not recommended unless there is a definite risk of acquiring pertussis.

The product information for Boostrix states that the vaccine may be considered during the 3rd trimester of pregnancy when the possible advantages outweigh the possible risks for the fetus.

The product information for Adacel and Boostrix states that there is no recommendation about vaccination against pertussis in subsequent pregnancies.

ATAGI recommends that pregnant women receive a dose of pertussis-containing vaccine with each pregnancy, ideally early in the 3rd trimester.

Vaccination after tetanus-toxoid vaccines

The product information for Adacel, Boostrix and Boostrix-IPV states that people should not receive a dTpa-containing vaccine within 5 years of a tetanus-toxoid vaccine.

ATAGI recommends that, if the person needs protection against pertussis, they can receive a dTpa-containing vaccine at least 4 weeks after a dT-containing vaccine.

Contraindications

The product information for all vaccines except ADT Booster states that these vaccines are contraindicated in children with either:

• encephalopathy of unknown aetiology occurring within 7 days after a vaccine dose, or
• neurologic complications occurring within 7 days after a vaccine dose

ATAGI recommends that the only contraindications are:

• anaphylaxis after a previous dose of any tetanus-toxoid vaccine
• anaphylaxis after any component of a tetanus-toxoid vaccine

The product information for Adacel Polio states that people should not receive this vaccine after a tetanus-prone wound. ATAGI recommends that people can receive Adacel Polio after a tetanus-prone wound.

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