In this chapter:
- Key information
- 20.1. Bacteriology
- 20.2. Clinical features
- 20.3. Epidemiology
- 20.4. Vaccines
- 20.5. Recommended immunisation schedule
- 20.6. Contraindications and precautions
- 20.7. Potential responses and AEFIs
- 20.8. Public health measures
- 20.9. Variations from the vaccine data sheets
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Mode of transmission
Environmental exposure to the bacillus, usually through contaminated wounds. The disease is not directly transmitted from person to person.
Between 3 and 21 days, commonly about 10 days; may vary from 1 day to several months.
Period of communicability
A person with tetanus is not infectious to others.
Incidence and burden of disease
Older individuals, usually women, who are less likely to have received a primary series of tetanus vaccine; and in unvaccinated children.
Dose, presentation, route
0.5 mL per dose.
DTaP-IPV-HepB/Hib: pre-filled syringe and glass vial. The vaccine must be reconstituted prior to injection.
DTaP-IPV, Tdap: pre-filled syringe.
Funded vaccine indications and schedule
During each pregnancy (recommended from 16 weeks’ gestation) for pertussis protection
6 weeks, 3 months and 5 months
45 years (catch-up, if individual has not received 4 previous tetanus doses)
Parents or primary caregivers of infants admitted to neonatal intensive or specialist baby care units for more than 3 days and whose mothers had not received Tdap at least 14 days prior to birth for pertussis protection
For vaccination of previously unimmunised or partially immunised patients
DTaP‑IPV‑HepB/Hib, DTaP-IPV or Tdap
For (re)vaccination of eligible patients
For boosting of patients with tetanus-prone wounds
If an injury is tetanus prone and there is any doubt about previous tetanus immunisation, the individual must be given tetanus immunoglobulin (TIG) and a 3-dose primary immunisation course. (see section 20.5.6).
Tetanus is caused by the action of tetanus toxin released by Clostridium tetani, a spore-forming gram-positive, motile, anaerobic bacillus. The most common source of environmental exposure to C. tetani spores and bacilli is soil. However, soil is not the only reservoir of the organism. Animals, both herbivores and omnivores, can carry C. tetani bacilli and spores in their intestines, and the organism is readily disseminated in their faeces. Once introduced into the relatively anaerobic conditions found in wound tissue, they germinate and produce toxin.
Tetanus spores or bacilli can easily be introduced into a wound at the time of injury, even when the injury is quite trivial. Contaminated wounds, especially wounds with devitalised tissue and deep-puncture trauma, are at greatest risk.
The clinical diagnosis of tetanus is characterised by muscular rigidity and very painful contraction spasms. When severe, it is associated with a characteristic facial grimace (risus sardonicus) and arching of the back (opisthotonus). The patient suffering from tetanus remains alert unless they become severely hypoxic.
The C. tetani toxin reaches the central nervous system via the axons and irreversibly binds to nerve terminals at the neuromuscular junction, blocking the release of inhibitory neurotransmitters and leading to the tetanic muscle spasms.
The incubation period is between 3 and 21 days, commonly about 10 days, but it has been reported to vary from one day to several months. The bacteria need an anaerobic environment in which to grow, and this is often found in damaged and necrotic tissue, although the inoculation site may appear insignificant. Initial symptoms include weakness, stiffness or cramps, and difﬁculty chewing or swallowing food. Reﬂex muscle spasms usually occur within one to four days of the initial symptoms, the interval being called the onset period. The shorter the incubation and onset periods, the more severe the disease. Even with modern intensive care, tetanus mortality is about 10 percent overall, and much higher in older people.
Neonatal tetanus, from infection of the umbilical stump, is the commonest form of the disease in some low-income countries, particularly where births take place at home without adequate sterile procedures and antenatal screening and immunisation programmes are disrupted.
A person with tetanus is not infectious to others, and vaccination provides individual protection only, with no herd immunity. Protective immunity can only be conferred by vaccination with tetanus toxoid and not through exposure to the natural pathogen or suffering tetanus. See section 20.5.2.
20.3.1. Global burden of disease
Tetanus infection continues to occur globally but is rare in high income countries. The estimated total number of tetanus cases (including neonatal cases) globally fell from more than 110,000 in 1980 to 15,000 in 2018.2 The highest numbers of cases were in India, Uganda and other sub-Saharan African countries. Tetanus in males in some sub‑Saharan countries has been associated with voluntary circumcision aimed at reducing the risk of HIV infection.
There were 1,803 neonatal tetanus cases reported worldwide in 2018, two-thirds of which were in Africa, and all the cases of tetanus reported in Afghanistan, Chad and Yemen were neonatal. Maternal and neonatal tetanus is described as a silent killer, since many cases are unreported. Worldwide, all countries are committed to ‘elimination’ of maternal and neonatal tetanus; that is, a reduction of neonatal tetanus incidence to below one case per 1,000 live births per year in every district. However, this goal has not yet been reached in 14 countries.
The incidence of tetanus reflects the effectiveness of the local immunisation programme, with low incidence in regions with high immunisation coverage. Global immunisation coverage for DTP is around 86 percent and 129 countries have reached at least 90 percent coverage for three doses of the DTP vaccine. In 2018, an estimated 19.4 million children aged under 1 year did not receive DTP. Of these, 13.5 million lack access to vaccination service and live in the poorest most fragile or conflicted states, and 60 percent live in 10 countries: Nigeria, India, Pakistan, Indonesia, Ethiopia, Philippines, Brazil, Angola and Vietnam.
20.3.2. New Zealand epidemiology
No cases of tetanus were notified during 2017-2019. There were 33 tetanus cases notified between 1997 and 2017. There were four cases in unvaccinated children (aged under 10 years), 14 cases in unvaccinated adults and three cases in vaccinated adults (the time since vaccination is not known). Two females aged 70 years or older died (one was not vaccinated and the vaccination status of the other was unknown).
For further information, see to the ESR’s notifiable disease reports.
Tetanus immunisation protects by stimulating the production of antitoxin, providing immunity against the effects of the toxin. It does not prevent C. tetani growing in a contaminated wound. The tetanus vaccine is prepared from cell-free toxin treated with formaldehyde to produce a toxoid. The toxoid is adsorbed onto an aluminium salt adjuvant to improve immunogenicity.
20.4.1. Available vaccines
Tetanus vaccine as a single antigen is no longer available in New Zealand. It is only available in combination with other vaccines.
The tetanus toxoid-containing vaccines funded as part of the Schedule are:
- DTaP-IPV-HepB/Hib (Infanrix-hexa, GSK): diphtheria, tetanus, acellular pertussis, inactivated polio, hepatitis B and Haemophilus influenzae type b vaccine
- DTaP-IPV (Infanrix-IPV, GSK): diphtheria, tetanus, acellular pertussis and inactivated polio vaccine
- Tdap (Boostrix, GSK): a lower adult dose of diphtheria and pertussis vaccine, together with tetanus vaccine.
See section 6.4.1 for more detailed vaccine information.
Other tetanus toxoid-containing vaccines registered (approved for use) and available (marketed) in New Zealand are:
- Tdap: Adacel (Sanofi)
- Tdap-IPV: Adacel Polio (Sanofi).
20.4.2. Efﬁcacy and effectiveness
Efficacy and effectiveness
Tetanus toxoid vaccine administered to pregnant women can prevent tetanus in their newborns (neonatal tetanus). Subsequent field assessments of the efficacy of two or more tetanus toxoid doses using data collected during neonatal tetanus mortality surveys demonstrated effectiveness of 70–100 percent.
A systematic review and meta-analysis concluded that immunisation of pregnant or childbearing-age women with two or more doses of tetanus toxoid reduces neonatal tetanus mortality by 94 percent (95% CI: 80–98).
Tetanus in adults is too rare for vaccine efﬁcacy to be tested in a clinical trial. However, the effectiveness of tetanus vaccine was clearly demonstrated in World War II, when only 12 cases of tetanus occurred among the 2.7 million wounded US army personnel (0.44 per 100,000), compared to 70 cases out of 520,000 wounded in World War I (13.4 per 100,000). Of the 12 cases, only four had completed primary immunisation. Immunised cases have less severe disease and a lower case-fatality.
Duration of protection
Serological studies show that the three-dose primary series of a tetanus vaccine given in infancy plus a booster during the second year of life, provide 3–5 years of protection against tetanus. WHO recommends six doses of tetanus-containing vaccine before age 18 years to induce immunity that lasts for much of adulthood. It is recommended that adults receive at least one booster dose, particularly where fewer than six doses have been given in childhood.
Over the last two decades, there has been a significant increase in the proportion of the adult population with protective antitoxin levels by mid-life. One mathematical model estimated protection to last for at least 30 years in most adults after vaccination. But as age increases, by every 10 years there is an associated 50 percent reduction in antitoxin levels.[12, 13] Even if documented as fully immunised, older adults are likely to have had fewer tetanus doses in their lifetime than adults younger than 30 years. Protection against the effects of tetanus toxin may be insufficient in adults who have not been adequately primed, and those aged over 65 years are at particularly increased risk of tetanus.
A single dose of tetanus toxoid produces a rapid anamnestic response.[15, 16, 17, 18] To ensure that there is adequate antitoxin to neutralise tetanus toxin in the case of a tetanus-prone injury, a booster dose is advised if it has been longer than 10 years since the last tetanus vaccine dose. The extent of wound contamination and delays in seeking medical assistance can result in high levels of tetanus toxin being released.
20.4.3. Transport, storage and handling
Transport according to the National Standards for Vaccine Storage and Transportation for Immunisation Providers 2017 (2nd edition).
Store at +2°C to +8°C. Do not freeze. DTaP-IPV-HepB/Hib and Tdap should be stored in the dark.
DTaP-IPV-HepB/Hib (Infanrix-hexa) must be reconstituted by adding the entire contents of the supplied container of the DTaP‑IPV‑HepB vaccine to the vial containing the Hib pellet. After adding the vaccine to the pellet, the mixture should be shaken until the pellet is completely dissolved. Use the reconstituted vaccine as soon as possible. If storage is necessary, the reconstituted vaccine may be kept for up to eight hours at 21°C.
20.4.4. Dosage and administration
The dose of DTaP-IPV-HepB/Hib, DTaP-IPV or Tdap is 0.5 mL administered by intramuscular injection (see section 2.2.3).
Co-administration with other vaccines
DTaP-IPV-HepB/Hib, DTaP-IPV and Tdap can be administered simultaneously (at separate sites) with other vaccines or IGs.
20.5.1. Usual childhood schedule
A primary course of tetanus vaccine is given as DTaP-IPV-HepB/Hib (Infanrix-hexa) at ages 6 weeks, 3 months and 5 months, followed by a dose of DTaP-IPV (Infanrix-IPV) at age 4 years (Table 20.1). A further booster is given at age 11 years (school year 7) as Tdap (Boostrix).
If a course of immunisation is late or interrupted for any reason, it may be resumed without repeating prior doses (see Appendix 2).
For adults and children who present with a tetanus-prone wound, boosters are recommended in accordance with the guidelines in the following sections and Table 20.2.
See Appendix 2 for detailed catch-up immunisation information.
Tdap may be used for primary immunisation of children aged 7 to under 18 years. Tdap can be given for vaccination of previously unimmunised or partially immunised adult patients.
Prior clinical tetanus does not usually confer immunity, and immunisation is required. In 1995, a 40-year-old man developed tetanus for a second time because he failed to complete the recommended course of immunisation after the ﬁrst episode of tetanus.
Dose intervals between Td and Tdap
20.5.3. Booster doses for adolescents and adults
Adults are recommended to have their tetanus immunisation status assessed at ages 45 and 65 years, and given either a booster dose of tetanus toxoid-containing vaccine if more than 10 years has elapsed since the previous dose, or a primary course, if there is any doubt about the adequacy of previous tetanus immunisation (uncertain or no history of a prior primary course). Protection against tetanus is expected to last at least 20 years following a booster dose after the primary series.
Tdap is recommended and funded:
- as a booster dose to all adolescents at school year 7 or age 11 years
- as a single dose for vaccination of individuals from aged 65 years old
- as a single dose for catch-up vaccination of individuals aged from 45 years old who have not had four previous tetanus doses.
These age-speciﬁc recommendations may facilitate the linkage of adult immunisation to the delivery of other preventive health measures. Offer a booster dose of Tdap for someone travelling overseas if it has been more than 10 years since the last dose (unfunded) (see section 6.5.3).
The administration of tetanus and diphtheria (Tdap) boosters given at ages 45 and 65 years, is also funded.
See Table 4.9 for occupational groups specifically recommended Tdap (not funded) vaccination due to risk of tetanus or pertussis.
20.5.4. Pregnancy and breastfeeding
Pregnant women should receive a dose of Tdap in every pregnancy so that antibodies can pass to the fetus to provide pertussis protection from birth (funded when given any time in second or third trimester). It is recommended to be given from 16 weeks’ gestation of every pregnancy, preferably in the second trimester to protect both the mother and her infant from pertussis (see section 15.5.2).
Tdap can be given to breastfeeding women.
Tetanus toxoid-containing vaccines are funded for (re)vaccination of eligible patients as follows, including prior to planned immunosuppression regimes or following immunosuppression. See also sections 4.2 and 4.3.
DTaP-IPV-HepB/Hib (Infanrix-hexa) and DTaP-IPV (Infanrix-IPV)
An additional four doses (as appropriate) of DTaP-IPV-HepB/Hib (for children aged under 10 years) or DTaP-IPV are funded for (re)vaccination of patients:
- post-HSCT or chemotherapy
- pre- or post-splenectomy
- pre- or post-solid organ transplant
- undergoing renal dialysis
- prior to planned or following other severely immunosuppressive regimens.
Up to five doses of DTaP-IPV-HepB/Hib (for children aged under 10 years) or DTaP-IPV are funded for children requiring solid organ transplantation.
An additional four doses (as appropriate) of Tdap (Boostrix) are funded for patients:
- post-HSCT or chemotherapy
- pre- or post-splenectomy
- pre- or post-solid organ transplant
- undergoing renal dialysis
- prior to planned or following other severely immunosuppressive regimens.
A single dose of Tdap is funded for parents or primary caregivers of infants admitted to a neonatal intensive care unit or special care baby unit for more than three days and whose mothers had not received Tdap at least 14 days prior to baby’s birth.
Following injury, it is essential that all wounds be adequately cleaned and devitalised tissue removed to reduce the level of contamination and tetanus toxin release. Further treatment depends on the circumstances of each case.
If the injury is considered to be tetanus-prone and there is any doubt about the adequacy of previous tetanus immunisation, the individual must have tetanus immunoglobulin (TIG) and commence or complete the recommended primary course of three doses of a tetanus toxoid-containing vaccine (depending on age and other antigens required: DTaP-containing vaccine or Tdap).
The definition of a tetanus-prone injury is not straightforward, because tetanus can occur after apparently trivial injury, such as from a rose thorn, or with no history of injury. However, there are certain types of wounds likely to favour the growth of tetanus organisms. These include:
- compound fractures
- bite wounds
- deep, penetrating wounds
- wounds containing foreign bodies (especially wood splinters)
- wounds complicated by pyogenic (pus-forming) infections
- wounds with extensive tissue damage (eg, crush injuries, avulsions, contusions or burns)
- wounds associated with vascular insufficiency (eg, leg or foot ulcers in the elderly)
- any superficial wound obviously contaminated with soil, dust or horse manure (especially if topical disinfection is delayed more than four hours)
- re-implantation of an avulsed tooth – in this case, minimal washing and cleaning of the tooth is conducted to increase the likelihood of successful re‑implantation.
General measures for the treatment of tetanus-prone wounds
Wounds or injuries should be classified as tetanus-prone or non-tetanus-prone as follows (see Table 20.2):
- non-tetanus-prone wounds – clean, minor wounds that are less than six hours old, non-penetrating and with negligible tissue damage
- tetanus-prone wounds – all wounds that may be contaminated or infected, and are penetrating, more than six hours old and with tissue damage.
Immunised individuals respond rapidly to a booster injection of tetanus toxoid-containing vaccine, even after a prolonged interval. Tetanus toxoid-containing vaccine and TIG should be given at the same time, but into different limbs and using separate syringes.
See also the IMAC factsheet Guidelines for the management of tetanus-prone wounds (available on the IMAC website).
- People who have experienced Arthus-type hypersensitivity reactions (see 20.7.2) after a previous dose of a tetanus toxoid-containing preparation should not receive tetanus toxoid-containing preparation more frequently than every 10 years, even if they have a wound that is neither clean nor minor.
- See Appendix 2 for catch-up schedules for previously unimmunised children. DTaP‑containing vaccine may be used in children aged under 10 years.
- TIG = tetanus immunoglobulin. The recommended dose is 250 IU given by IM injection as soon as practicable after injury. If more than 24 hours has elapsed, 500 IU is recommended. A dose of TIG can be given for up to 3 weeks after injury.
- If appropriate, this may count as the booster dose at age 45 or 65 years.
- To complete the 3-dose primary immunisation course, give 1–3 doses at not less than 4‑weekly intervals.
Tetanus immunoglobulin availability and storage
Tetanus immunoglobulin (TIG) is issued in ampoules, each containing 250 IU of human tetanus antitoxin. (Ampoules of 2,000 IU are used for treatment and not for prophylaxis.) These should be protected from light and stored in a refrigerator at +2°C to +8°C. They must never be frozen. TIG is given intramuscularly.
The recommended dose to prevent tetanus is 250 IU of TIG for recent injuries, but this should be increased to 500 IU if more than 24 hours has elapsed since injury, or if there is a risk of heavy contamination or following burns. A dose of TIG can be given for up to 3 weeks after injury.
There is no need to test the patient’s sensitivity before administering TIG, but caution is necessary if the patient is known to suffer complete immunoglobulin A (IgA) deﬁciency. In this situation, specialist help should be sought (see section 4.3).
Patients with impaired immunity who suffer a tetanus-prone wound may have failed to respond to prior vaccination and may therefore require TIG.
TIG can be given in pregnancy if clinically indicated. Whilst the safety of TIG for use in pregnancy has not been established in controlled clinical trials, no known risk to the fetus has been associated with use in pregnancy.
Immunisation with Tdap or another tetanus toxoid-containing vaccine should not be repeated in individuals who have had previous severe hypersensitivity reactions to the vaccine or a vaccine component. Most cases of hypersensitivity have been reported in individuals who have had an excessive number of booster injections outside the guidelines noted above.
Protection against the risk of tetanus is paramount if the wound is thought to be tetanus-prone. Immunisation should not be postponed because the patient has a minor infection.
People who have experienced Arthus-type hypersensitivity reactions (see section 20.7.2) after a previous dose of a tetanus toxoid-containing preparation should not receive tetanus toxoid-containing preparation more frequently than every 10 years, even if they have a wound that is neither clean nor minor. Arthus-type reactions are rare in children and did not occur during the clinical trial of Tdap vaccines.
See section 15.6.2 for precautions to pertussis-containing vaccines, including DTaP‑IPV-HepB/Hib.
20.7.1. Potential responses
Tetanus toxoid combination vaccines have not been associated with any safety concerns. Sterile abscesses and persistent nodules at the injection site may develop if the injection is not given deeply enough into the muscle. Mild discomfort or pain at the injection site persisting for up to a few days is common.
The 1994 US Institute of Medicine review of adverse events from tetanus vaccine concluded that the evidence supported a link with brachial plexus neuropathy (brachial neuritis) at a rate of 0.5–1 per 100,000 doses within four weeks of immunisation. Occurrence of brachial neuritis following vaccination does not preclude the future use of a tetanus-toxoid containing vaccine in the same person.
Severe local reactions (including large injection-site swelling) called Arthus reactions, immune-complex mediated hypersensitivity reactions that were associated with older tetanus and diphtheria toxoid-containing vaccines. Historical data on multiple doses of Td and tetanus toxoid vaccines indicate that hypersensitivity was associated with very high levels of pre‑existing antibody.[9, 30]
No increased risk of GBS has been observed with use of tetanus toxoid-containing vaccines, and therefore a history of GBS is not a contraindication to receiving a tetanus toxoid-containing vaccine. However, out of prudence, it is recommended that having GBS within six weeks of a tetanus toxoid-containing vaccine is a precaution to receiving a further dose.[9, 30]
All cases of tetanus must be notiﬁed immediately on suspicion to the local medical officer of health, who should be provided with as accurate an immunisation history as possible.
Tdap vaccine is not approved for use (registered) for primary immunisation. However, adults aged over 18 years may receive Tdap (funded) for catch-up of the primary schedule (see Appendix 2).
See section 15.9 for variations from the DTaP-IPV-HepB/Hib (Infanrix-hexa), DTaP-IPV (Infanrix-IPV) and Tdap (Boostrix) data sheets.
- World Health Organization. 2017. Tetanus vaccines: WHO position paper – February 2017. Weekly Epidemiological Record 92(6): 53–76.
- World Health Organization. 2019. Tetanust (Total) Reported Cases. 10 December. URL: http://apps.who.int/immunization_monitoring/globalsummary/timeseries/tsincidencentetanus.html (accessed 20 May 2020).
- Dalal S, Samuelson J, Reed J, et al. 2016. Tetanus disease and deaths in men reveal need for vaccination. Bulletin of the World Health Organization 94(8): 613–21.
- World Health Organization. 2019. Tetanus (Neonatal) Reported Cases. 10 December. URL: http://apps.who.int/immunization_monitoring/globalsummary/timeseries/tsincidencentetanus.html (accessed 20 May 2020).
- World Health Organization. 2019. Protecting All Against Tetanus: Guide to sustaining maternal and neonatal tetanus elimination (MNTE) and broadening tetanus protection for all populations. . Licence: CC BY-NC-SA 3.0 IGO ed (ed). Geneva: World Health Organization. URL: https://apps.who.int/iris/bitstream/handle/10665/329882/9789241515610-eng.pdf?ua=1 (accessed 20 May 2020).
- World Health Organization, UNICEF. 2019. Progress and Challenges with Achieving Universal Immunisation Coverage: 2018 WHO/UNICEF estimates of National Immunization Coverage. Monitoring and Surveillance. July. URL: https://www.who.int/immunization/monitoring_surveillance/who-immuniz.pdf?ua=1 (accessed 3 July 2020).
- Institute of Environmental Science and Research Ltd. 2019. Notifiable Diseases in New Zealand: Annual Report 2017. Porirua, New Zealand. URL: https://surv.esr.cri.nz/PDF_surveillance/AnnualRpt/AnnualSurv/2017/2017AnnualNDReport_FINAL.pdf (accessed 3 July 2020).
- Institute of Environmental Science and Research Ltd. 2016. Notifiable Diseases in New Zealand: Annual Report 2015 (ed). Porirua, New Zealand: The Institute of Science and Environmental Research Ltd. URL: https://surv.esr.cri.nz/PDF_surveillance/AnnualRpt/AnnualSurv/2015/2015AnnualReportFinal.pdf (accessed 3 July 2020).
- Roper MH, Wassilak SGF, Scobie HM, et al. 2018. Tetanus toxoid. In Plotkin SA, Orenstein WA, Offit PA, et al (eds) Plotkin’s Vaccines (7th edition). Elsevier: Philadelphia, PA.
- Lu X, Quinn HE, Menzies RI, et al. 2018. Tetanus immunity and epidemiology in Australia, 1993–2010. Infect Disord Drug Targets.
- Hammarlund E, Thomas A, Poore EA, et al. 2016. Durability of vaccine-induced immunity against tetanus and diphtheria toxins: a cross-sectional analysis. Clinical Infectious Diseases 62(9): 1111–18.
- Maple PA, Jones CS, Wall EC, et al. 2000. Immunity to diphtheria and tetanus in England and Wales. Vaccine 19(2–3): 167–73.
- Moughty A, Donnell JO, Nugent M. 2013. Who needs a shot ... a review of tetanus immunity in the West of Ireland. Emergency Medicine Journal 30(12): 1009–11.
- Weinberger B, Schirmer M, Matteucci Gothe R, et al. 2013. Recall responses to tetanus and diphtheria vaccination are frequently insufficient in elderly persons. PloS One 8(12): e82967.
- Alagappan K, Rennie W, Lin D, et al. 1998. Immunologic response to tetanus toxoid in the elderly: one-year follow-up. Annals of Emergency Medicine 32(2): 155–60.
- Björkholm B, Hagberg L, Sundbeck G, et al. 2000. Booster effect of low doses of tetanus toxoid in elderly vaccinees. European Journal of Clinical Microbiology and Infectious Diseases 19(3): 195–9.
- Shohat T, Marva E, Sivan Y, et al. 2000. Immunologic response to a single dose of tetanus toxoid in older people. Journal of the American Geriatrics Society 48(8): 949–51.
- Van Damme P, McIntyre P, Grimprel E, et al. 2011. Immunogenicity of the reduced-antigen-content dTpa vaccine (Boostrix®) in adults 55 years of age and over: a sub-analysis of four trials. Vaccine 29(35): 5932–9.
- Smith J. 1995. Tetanus infection may not confer immunity. New Zealand Public Health Report 6: 53.
- Beytout J, Launay O, Guiso N, et al. 2009. Safety of Tdap-IPV given one month after Td-IPV booster in healthy young adults: a placebo-controlled trial. Hum Vaccin 5(5): 315–21.
- Talbot EA, Brown KH, Kirkland KB, et al. 2010. The safety of immunizing with tetanus-diphtheria-acellular pertussis vaccine (Tdap) less than 2 years following previous tetanus vaccination: Experience during a mass vaccination campaign of healthcare personnel during a respiratory illness outbreak. Vaccine 28(50): 8001–7.
- Liang JL, Tiwari T, Moro P, et al. 2018. Prevention of pertussis, tetanus, and diphtheria with vaccines in the United States: recommendations of the Advisory Committee on Immunization Practices (ACIP). MMWR: Recommendations and Reports 67(2): 1–44.
- Havers FP, Moro PL, Hunter P, et al. 2020. Use of tetanus toxoid, reduced diphtheria toxoid, and acellular pertussis vaccines: updated recommendations of the Advisory Committee on Immunization Practices – United States, 2019. MMWR: Morbidity and Mortality Weekly Report 69(3): 77–83.
- Australian Technical Advisory Group on Immunisation. 2018. Australian Immunisation Handbook (ed). Canberra: Australian Government Department of Health. URL: https://immunisationhandbook.health.gov.au/ (accessed October 2019).
- American Academy of Pediatrics. 2018. Tetanus. In Kimberlin D, Brady M, Jackson M, et al (eds) Red Book: 2018 Report of the Committee on Infectious Diseases. Elk Grove Village, IL. URL: https://redbook.solutions.aap.org/redbook.aspx (accessed 3 July 2020).
- Mark A, Carlsson RM, Granstrom M. 1999. Subcutaneous versus intramuscular injection for booster DT vaccination of adolescents. Vaccine 17(15–16): 2067–72.
- Klein NP, Hansen J, Lewis E, et al. 2010. Post-marketing safety evaluation of a tetanus toxoid, reduced diphtheria toxoid and 3-component acellular pertussis vaccine administered to a cohort of adolescents in a United States health maintenance organization. Pediatric Infectious Disease Journal 29(7): 613–17.
- Yih WK, Nordin JD, Kulldorff M, et al. 2009. An assessment of the safety of adolescent and adult tetanus-diphtheria-acellular pertussis (Tdap) vaccine, using active surveillance for adverse events in the Vaccine Safety Datalink. Vaccine 27(32): 4257–62.
- Vaccine Safety Committee: Institute of Medicine. 1994. Diphtheria and tetanus toxoids. In Stratton KR, Howe CJ, Johnston RB (eds) Adverse Events Associated with Childhood Vaccines: Evidence bearing on causality. National Academies Press: Washington, DC.