Introduction

The implementation of immunisation programmes has become a global standard in healthcare. These vaccination schedules have improved the levels of immunity in populations and reduced the incidence of some diseases. Vaccinations have also led to the eradication of major infections, notably smallpox. The smallpox vaccine, developed by Edward Jenner in 1796, proved to completely eradicate the infection by 1980, saving millions of people from long-term issues like scarring and blindness.¹ Amongst the list of life-saving vaccinations is the tetanus vaccine. Tetanus is a disease that has become extremely rare, and its incidence continues to fall.² This article will highlight the immunity gained from the tetanus vaccine.

Basics of the immune response

To understand the role of the tetanus vaccine and its duration of effect, it’s important to have a basic background of the body’s immune response. The immune system fights infections and other foreign substances (called antigens). The cells responsible for carrying this out are white blood cells.

When an individual acquires a certain infection for the first time, white blood cells circulating in the blood will notice the foreign antigens. Because these antigens were not known to the body before, an “innate” immune response is activated. White blood cells will attempt to kill off the antigen, and will also remember’ that infection. So if the person is infected with the same infection, again, it will be recognised quickly, and the right antibodies (cells specific to the antigen and effective at removing the infection) will be promptly produced in large quantities. 

As you can appreciate, the innate response itself is not specific to the antigens/infection acquired, so it’s not the most effective at battling the infection. In the other response we mentioned, that where the body is more prepared and/or is adapting to the infection, this is known as adaptive immunity. 

What is tetanus?

In the past, parents often warned their children about cuts and scratches. Of course, this is partly for the sake of the child not getting physically hurt, but the other important thing people looked out for was a tetanus infection. This infection is caused by Clostridium tetani and leads to severe signs and symptoms.³

The classical feature is widespread, painful muscle stiffness. It is the toxin produced by the bacteria that leads to these severe muscle contractions. As a result, infected individuals may have a "lockjaw,"  where they are not able to swallow, eat, or talk due to stiffening of the neck, face, and jaw muscles. Muscles are essential for other functions such as breathing (the diaphragm is a muscle!) - so a tetanus infection that is not promptly managed can lead to respiratory failure and other life-threatening outcomes. The CDC recognises, that muscle spasms in children can be so severe that they may break the person’s spine.⁴ As with any infection, patients could also have fevers, chills, sweats, headaches, fatigue and nausea. 

Unlike many other infections, tetanus is not transmitted from person to person. The tetanus bacteria is found in the environment, particularly in organic (or organic-containing) materials like soil and manure, as well as dust and metals. A common scenario you may come across when reading about tetanus is someone stepping on a nail or another sharp object that causes a wound. But generally speaking, any person with a wound and a mechanism of injury that involves sharps or the ground, should be checked for their tetanus status. 

Are there any side effects of the vaccine?

Many vaccines have side effects because they introduce something to the body and try to build an immune response. A common misconception is that having a flu-like illness after a vaccine means that it is harmful to the person or that it should be avoided. But this response is actually expected and shows that the body is indeed reacting to the substances in the vaccine. This should then lead to a better and quicker response to the infection, should someone actually acquire it. Generally, vaccines do not prevent you from getting an infection, but they should improve your response to the infections you have been vaccinated against. This has overall led to increased survival rates, reduced duration of sickness, and fewer complications of the disease.

Most people will experience little to no side effects following the tetanus vaccine.⁵ Some side effects include flu-like illness, tenderness at the site of injection, nausea, and fatigue. The more serious side effects can include high-grade fever, inconsolable crying (in children/infants), and seizures. If there are any concerns, professional medical support should be sought. Teens can faint/immediately after getting the injection the exact reasons for that are not known, but recovery is expected, and usually, no other concerns are found.⁶

Immunity from the tetanus vaccine

For children and teenagers, the tetanus injection is usually combined with two other vaccines: Diphtheria, and Pertussis (whooping cough).⁶ The vaccination is named  DTP. Currently, in the NHS, Tetanus is part of a 6-in-1 vaccine.⁷ The vaccine includes Tetanus, Diphtheria, and Pertussis, as well as Hepatitis B, Haemophilus influenzae type B, and Polio. 

The general recommendation for tetanus immunisation is that a full course includes 5 vaccinations. One tetanus vaccine is administered at the following ages: 2 months, 3 months, 4 months, 3 years + 4 months, and around 14 years. The first three tetanus vaccinations are part of the 6-in-1 vaccine, but the latter two are boosters. While immunity from the full tetanus immunisation course is long-term, the guidelines around managing wounds and whether someone should get more tetanus vaccines or immunoglobulins depend on the extent of the wound, mode of injury, and signs/suspicion of infection. Vaccination courses may become less effective over time, so reinforcements are required sometimes. Generally, if an individual has acquired a wound but has a complete tetanus immunisation history, and the last vaccine was less than 10 years ago, a person is unlikely to receive any further vaccines. If the last vaccine was more than 10 years ago, then a clinician will decide whether this is a tetanus-prone wound or a high-risk wound, which will alter the management. If a person is unsure of their tetanus status or has not completed a full course of vaccinations, they can be given a tetanus injection, regardless of the severity. Whether someone is offered further treatments or immunoglobulins depends on the severity of the wound.

The Department of Health’s ‘The Green Book’ outlines the detailed criteria and guidelines for tetanus immunisations.⁸

Summary

Immunity from the tetanus vaccine is long-term, but reinforcements are important beyond 10 years since the last vaccination. This ensures that the risk of infection is low, especially in tetanus-prone cases. As with any vaccination, people have the right to refuse treatment, but it is important that you are well-informed prior to making that decision.