Tetanus

1. Tetanus Trisha McKeown RANP IU, Nenagh

2. What is tetanus? • An infectious disease caused by contamination of wounds from the bacteria Clostridium tetani, or the spores they produce that live in the soil, and animal feces • Greek words -“tetanosandteinein”, meaning rigid and stretched, which describe the condition of the muscles affected by the toxin, tetanospasmin, produced by Clostridium tetani

3. How do people get tetanus? • Tetanus spores are found throughout the environment, usually in soil, dust, and animal waste. • Tetanus is acquired through contact with the environment; it is not transmitted from person to person.

4. The usual locations for the bacteria to enter the body • Puncture wounds (such as those caused by rusty nails, splinters, or insect bites.) • Burns, any break in the skin, and IV drug access sites are also potential entryways for the bacteria.

5. Route of Entry • Apparently trivial injuries • Animal bites/human bites • Open fractures • Burns • Gangrene • In neonates usually via infected umbilical stumps • Abscess • Parenteral drug abuse

6. Epidemiology • Tetanus is an international health problem. The disease occurs almost exclusively in persons who are unvaccinated or inadequately immunized. • Tetanus occurs worldwide but is more common in hot, damp climates with soil rich in organic matter. • More common in developing and under developing countries. • More prevalent in industrial establishment, where agricultures workers are employed. • Tetanus neonatorum is common due to lack of MCH care.

7. Incubation period • Varies from 1 day to several months. It is defined as the time from injury to the first symptom.

8. Period of onset • It is the time from first symptoms to the reflex spasm. • An incubation period of 4 days or less or • A period of onset of less than 48 hr is associated with the development of severe tetanus.

9. 1. C. tetani enters body from /through wound. 2. Stays in sporulated form until anaerobic conditions are presented. 4. Tetnospasmin spreads using blood and lymphatic system, and binds to motor neurons. 3. Germinates under anaerobic conditions and begins to multiply and produce tetnospasmin. 5. Travels along the axons to the spinal cord. 6. Binds to sites responsible for inhibiting skeletal muscle contraction.

10. How the toxin acts? • Blocks the release of inhibitory neurotransmitters (glycine and gamma-amino butyric acid) across the synaptic cleft, which is required to check the nervous impulse. • If nervous impulses cannot be checked by normal inhibitory mechanisms, it leads to unopposed muscular contraction and spasms that are characteristic of tetanus.

11. Tetanus prone wound • A wound sustained more than 6 hr before surgical treatment. • A wound sustained at any interval after injury which is puncture type or shows much devitalised tissue or is septic or is contaminated with soil or manure.

12. Clinical features • Contraction of the muscles at the angle of mouth and frontalis (Risussardonicus) • Trismus (Lock Jaw): Spasm of Masseter muscles. • Spasm of extensor of the neck, back and legs to form a backward curvature.(Opisthotonus) • Muscle spasticity • Prolonged muscular action causes sudden, powerful, and painful contractions of muscle groups. This is called tetany. These episodes can cause fractures and muscle tears. • If respiratory muscle is involved – apnoea.

13. Signs and symptoms Other symptoms include: • Drooling • Excessive sweating • Fever • Hand or foot spasms • Irritability • Swallowing difficulty • Uncontrolled urination or defecation

14. Diagnosis • There are currently no blood tests that can be used to diagnose tetanus. Diagnosis is done clinically Differential Diagnosis • Masseter muscle spasm due to dental abscess • Dystonic reaction to phenothiazine • Rabies • Hysteria

15. Tetanus vaccine in children • Tetanus vaccine is given as part of the routine childhood immunisation programme, together with diphtheria, pertussis, HiB, and inactivated polio, hepatitis b vaccines (referred to as the “6-in-1” vaccine). Vaccination is given at 2, 4 and 6 months of age. • Booster vaccine doses are given at 4-5 years of age (as part of the 4 in 1 vaccine DTaP/IPV) and again between 11-14 years of age (as part of the Td vaccine

16. Tetanus vaccination in older children and adults • Adults or children older than 10 years of age who have not been immunised, or only partially immunised, should receive tetanus vaccination according to the recommended schedule, using a vaccine called “Td” (combined tetanus/low dose diphtheria vaccine) - which is appropriate for this age group.

17. Tetanus vaccination after an injury • Individuals who have wound injuries are medically assessed to determine what treatment is needed to prevent tetanus. • The treatment recommended will depend on history of tetanus vaccination, type of wound and whether it is considered to be a ‘tetanus prone wound’ (such as wounds contaminated with dirt, faeces, soil and saliva)

18. Tetanus Prone Wound • Wounds or burns that require surgical intervention that is delayed for more than six hours • Wounds or burns that show a significant degree of devitalised tissue or a puncture-type injury, particularly where there has been contact with soil or manure • Wounds containing foreign bodies • Compound fractures • Wounds or burns in patients who have sepsis

19. How does tetanus vaccine work? • The vaccine is made of inactivated toxins from the bacteria , this is called a toxoid preparation. • Vaccination stimulates the body to produce serum anti-toxin. • A total of five doses of tetanus toxoid containing vaccine at the appropriate intervals are considered to give lifelong immunity. • Recovery from tetanus may not result in immunity, and vaccination following tetanus is indicated.

20. Vaccine site • The antero-lateral thigh and deltoid regions avoid major nerves and blood vessels • Immunisations should not be given into the buttock due to risk of damage to the sciatic nerve and risk of injecting into fat which can reduce the effectiveness of some vaccines.

21. Definitions Td:- Tetanus, low-dose diphtheria DTaP:- Diphtheria, Tetanus and acellular Pertussis vaccine Hib:- Haemophilius influenzae b vaccine IPV:- Inactivated Polio Virus vaccine Tdap:- Tetanus, low-dose diphtheria and low-dose acellular pertussis vaccine TIG:- Tetanus Immunoglobulin.

22. IMPORTANT: • Consider TIG if wound contaminated with stable manure, or extensive devitalised tissue. • Give TIG if HIV positive, irrespective of vaccine status. • If both TIG plus a vaccine are to be given, administer at separate sites. • Refer to GP for follow-up vaccines. • Batch numbers and expiry dates must be recorded for all vaccines given. • This information MUST be communicated to the patient’s GP so that: • Duplication of vaccination does not occur. • Full records may be passed onto the relevant agencies in order that a full nationwide database is kept of batch numbers and expiry dates of vaccines given to children.

23. Specific Tetanus immunoglobulin Indications • Those with tetanus-prone wounds who have not received at least 3 doses of tetanus toxoid and their last dose within 10 years • Patients with impaired immunity who suffer a tetanus prone wound – may in addition require anti-tetanus immunoglobulin • Patients who have suffered a high-risk wound, regardless of vaccine history • If HIV positive give TIG irrespective of vaccine status • Bring to room temperature before administration

25. References • http://www.immunisation.ie/en/ • World Health Organisation, 2017