The tetanus toxoid is an FDA approved vaccination given alone or in conjunction with other vaccines. It is protective against effects from a gram-positive bacillus, Clostridium tetani.  This bacteria produces a neurotoxin called tetanospasmin, which blocks the release of an inhibitory neurotransmitter and leads to unopposed muscle contractions and spasms.[1]

The World Health Organization recommends receiving the primary series of tetanus vaccinations during adolescence. Due to the requirement for primary immunization, an absorbed form containing multiple antigens is usually utilized.[2] Children must complete the 5-dose DTaP (diphtheria, tetanus, acellular pertussis) vaccination series before the age of 7.[3] The CDC recommends the first dose at two months old, the second dose at three months old, the third dose at four months old, the fourth dose between months 15 and 18, and the fifth dose between the ages of 4 and 6 years old. Following the first series of vaccinations, the recommendation is that adults receive boosters with Tdap (same components as DTaP, but reduced doses of diphtheria and pertussis) every ten years. Studies indicate that the Tdap booster given ten years after the initial series of vaccines is usually well-tolerated and effectively immunogenic.[4]

Furthermore, tetanus toxoid can be used alone if needed in particular circumstances. It is highly effective when used prophylactically in cases when dealing with wound care and management. The Tdap booster vaccination should also be considered in patients with any wound injury who have had less than three tetanus toxoid doses, received their last dose more than ten years ago, or if their immunization history is unknown.[5]

Vaccinations exert their effect on the human body via priming our active immune system. Following the administration of the tetanus toxoid,  the immune system is stimulated and responds to the antigens present in the vaccine. TH2 and B cells are activated, which then go on to produce immunoglobins against the toxoid, allowing for adequate protection against future infections. This process requires multiple dosages to achieve a high immune response; however, it bears mentioning that there is no chance for the toxoid to exhibit its pathogenic features as it is an inactivated vaccine.[6]

Preparation of the tetanus toxoid is via inactivation of the toxigenic strains of Clostridium tetani. The toxic strains are grown in liquid media, purified, then treated with formaldehyde to take away the pathogenic properties. Following purification and sterilization, tetanus toxoid is combined with aluminum or calcium salts.  This toxoid antigen is then usually used in combination with Diptheria and pertussis antigens in a vaccination form.

The DTaP vaccine is a 0.5 mL dose, and it is given intramuscularly. For patients who are infants to two years old, the anterolateral aspect of the thigh is the preferred injection site.  For children aged three and older, the deltoid muscle is the preferred injection site.[1]  This regimen is a 5-dose series starting at the age of two months and ending at six years old.

• First dose: 2 months old, must be at least six weeks old
• Second dose: 4 months old
• Third dose: 6 months old
• Fourth dose: 15 months to 18 months old, must be at least 12 months old, given at a minimum of six months after the third dose
• Fith dose: 4 years to 6 years old, must be at least four years old, given at a minimum of six months after the fourth dose

As most DTaP vaccinations contain higher levels of diptheria in comparison to tetanus and pertussis, Tdap has higher levels of tetanus in comparison to diphtheria and pertussis. The Tdap vaccine is a 0.5 mL dose, and it is also given as an intramuscular injection. This vaccine should only be used as a booster every ten years, starting at ages eleven to twelve years old.

Although vaccinations containing the tetanus toxoid are generally safe, some adverse effects can occur.  Any vaccine with tetanus toxoid as a component has the potential to cause brachial neuritis.[7]  Also known as neuralgic amyotrophy,  brachial neuritis is an immune-mediated inflammatory process involving peripheral nerves.  Patients usually present with pain and muscle weakness, and sometimes cases can be severe; however, this is extremely rare, and symptoms typically subside on their own.[8]

A study of 740 patients with adverse effects to the tetanus toxoid showed that, when present, the most common symptoms are local edema and tenderness, fever, and anaphylactoid response.[9]

In the 1990s, whole-cell pertussis was replaced with acellular pertussis, which is a common component of vaccines containing the tetanus toxoid. Before the switch to acellular pertussis, swelling, redness, and pain at the injection site were commonly noted adverse events; however, these reactions are much less common today.[10]

The tetanus toxoid is generally safe for the human population; however, there are specific contraindications. One contraindication includes past anaphylaxis reaction to the tetanus toxoid. Further, in the case where encephalopathy occurs within seven days of administration of the tetanus toxoid and no other cause is found, this can also be a contraindication for future injections.[1]