Tetanus

Abstract

Tetanus is acquired through exposure to the environmental spore-forming Gram-positive bacillus Clostridium tetani, which may infect human wounds and cause disease by production of an exotoxin (tetanospasmin). There is no human-to-human transmission. The disease occurs worldwide and it is sporadic in high-income countries with universal access to well-accepted immunization programs. It is more common in agricultural regions and in low-income countries where contact with animal excreta is more likely and immunization programs are inadequate. Neonatal tetanus (NNT) following unclean deliveries and poor postnatal hygiene is still responsible for the majority of tetanus cases and deaths; the majority of NNT occurs in poor Asian and African countries, whereas in high-income countries the disease is extremely rare. Three forms of clinical disease can be distinguished: the most common form is generalized tetanus, whereas local tetanus and cephalic tetanus are rare. Neonatal tetanus (NNT) is a form of generalized tetanus in newborns. The case fatality rate of tetanus is high, 3%–95% depending on age, immune- and immunization-status, form of disease, and availability of proper medical care. The efficacy of tetanus toxoid vaccines was never formally studied, but cases in adequately vaccinated subjects are extremely rare and impact data (e.g. for NNT) convincingly show high vaccine effectiveness. WHO estimates that in 2018, 25,000 newborns died from NNT, an 88% reduction from the situation in 2000.