TetanusTetanus

- Prof. N. Shantharam- Prof. N. Shantharam

Tetanus Tetanus (cont’d)(cont’d)

Tetanus is not common in U.S.A. Tetanus is not common in U.S.A. because of mandatory vaccination because of mandatory vaccination

HHowever, a few cases/year in non-owever, a few cases/year in non-vaccinated or improper booster vaccinated or improper booster individualsindividuals

Tetanus is still very common in Third World Tetanus is still very common in Third World countries—causing several hundred countries—causing several hundred thousand deaths per yearthousand deaths per year

Many of these deaths involve neonatal Many of these deaths involve neonatal tetanus due to the umbilical cord being tetanus due to the umbilical cord being unsterilely cutunsterilely cut

IndiaIndia • Tetanus is important endemic infection in Tetanus is important endemic infection in

indiaindia• FactorsFactors : :

– Hand washing Hand washing – Delivery practices Delivery practices – Traditional birth customsTraditional birth customs– Interest in immunization Interest in immunization

prior to the national immunization programme prior to the national immunization programme an estimatedan estimated

3.5 lack children are died annually3.5 lack children are died annually70,000 cases continue to occur largely in the 70,000 cases continue to occur largely in the

OBIMARU states were TT immunization OBIMARU states were TT immunization coverage is less than national average (70%)coverage is less than national average (70%)

TetanusTetanus agentagent

Clostridium TetaniClostridium Tetani

GGram positiveram positive

Spore-formingSpore-forming

Anaerobic rodAnaerobic rod

Clostridium tetani Gram Stain

NOTE: Round terminal spores give cells a “drumstick” or “tennis racket” appearance.

Tetanus Tetanus (cont’d)(cont’d)

Entry of Entry of C. tetani C. tetani into the body usually into the body usually involves implantation of spores into a involves implantation of spores into a woundwound

After gaining entry, After gaining entry, C. tetaniC. tetani spores spores can persist in the body for months, can persist in the body for months, waiting for the proper low oxygen waiting for the proper low oxygen growth conditions to developgrowth conditions to develop

Tetanus Tetanus (cont’d)(cont’d)

When the oxygen levels of the When the oxygen levels of the surrounding tissue is sufficiently surrounding tissue is sufficiently low, the implanted low, the implanted C. tetaniC. tetani spore spore then germinates into a new, active then germinates into a new, active vegetative cell that grows and vegetative cell that grows and multiplies and most importantly multiplies and most importantly produces tetanus toxinproduces tetanus toxin

Tetanus Tetanus (cont’d)(cont’d)

As growing cells of As growing cells of C. tetani C. tetani produce produce tetanospasmin at the wound site, the toxin tetanospasmin at the wound site, the toxin starts to migrate along nerves and starts to migrate along nerves and acts acts mainlymainly on 4 areas of nervous system:on 4 areas of nervous system:

– Motor end plateMotor end plate– Spinal cord Spinal cord – BrainBrain

– Sympathetic systemSympathetic system

where it blocks the release of inhibitory where it blocks the release of inhibitory neurotransmittersneurotransmittersAs a consequence of too much “activator As a consequence of too much “activator transmitters”, muscles are Over stimulated to transmitters”, muscles are Over stimulated to repeatedly contract—called spastic paralysisrepeatedly contract—called spastic paralysis

Mechanism of Action of Tetanus Toxin

Reservoir• Spores of C. tetani are found in soil, dustSpores of C. tetani are found in soil, dust, , intestinal tracts of animals intestinal tracts of animals and humans and humans • Throughout the world Spores are very resistant to harsh conditions Throughout the world Spores are very resistant to harsh conditions like: like:

– heatheat– radiationradiation– chemicalschemicals– DryingDrying

SporesSpores can survive for a long time in environment---100yrs possibly! can survive for a long time in environment---100yrs possibly!

• CommunicabilityCommunicability

• Tetanus is not contagious from person to person.Tetanus is not contagious from person to person.• It is the only vaccine-preventable disease that is infectious but not It is the only vaccine-preventable disease that is infectious but not contagious.contagious.

• Temporal pattern: Peak in winter and summer seasonTemporal pattern: Peak in winter and summer season

• Incubation Period: 8 DAYS ( 3-21 DAYS)Incubation Period: 8 DAYS ( 3-21 DAYS)

Host Factors• Age : I t is the disease of active age (5-40 Age : I t is the disease of active age (5-40

years), New born baby, female during years), New born baby, female during delivery or abortiondelivery or abortion

• Sex : Higher incidence in males than femalesSex : Higher incidence in males than females

• Occupation : Agricultural workers are at Occupation : Agricultural workers are at higher riskhigher risk

• Rural –Urban difference: Incidence of tetanus Rural –Urban difference: Incidence of tetanus in urban areas is much lower than in rural in urban areas is much lower than in rural areasareas

• Immunity : Herd immunity does not protect Immunity : Herd immunity does not protect the individualthe individual

• Environmental and social factors: Unhygienic Environmental and social factors: Unhygienic custom habits,Unhygienic delivery practicescustom habits,Unhygienic delivery practices

Sequence of events

Lock JawLock Jaw

Stiff NeckStiff Neck

Difficulty SwallowingDifficulty Swallowing

Muscle RigidityMuscle Rigidity

SpasmsSpasms

Risus Sardonicus in Tetanus Patient

A person suffering from tetanus undergoes convulsive muscle contractions of the jaw--called LOCKJAW

Opisthotonos in Tetanus Patient

The contractions by the muscles of the back and extremities may become so violent and strong that bone fractures may occur

CEPHALIC TETANUS : A Rare Form of Localized Tetanus(Courtesy : Google image on tetanus)

Unfortunately, the affected individual is conscious throughout the illness, but cannot stop these contractions

Tetanus Tetanus (cont’d)(cont’d)

Death may occur from tetanus, often Death may occur from tetanus, often from cardiac (heart) and respiratory from cardiac (heart) and respiratory (lung) effects or secondary (lung) effects or secondary complications from the infectioncomplications from the infection

Types of tetanus

• TraumaticTraumatic

• PuerperalPuerperal

• OtogenicOtogenic

• IdiopathicIdiopathic

• Tetanus neonatorum (8Tetanus neonatorum (8thth day day disease) disease)

•Local tetanus is an uncommon form of the disease,in which patients have persistent contraction of muscles in the same anatomic area as the injury. Local tetanus may precede the onset of generalized tetanus but is generally milder.Only about 1%of cases are fatal.

•Cephalic tetanus is a rare form of the disease,occasionally occurring with otitis media (ear infections)in which C.tetani is present in the flora of the middle ear,or following injuries to the head.There is involvement of the cranial nerves,especially in the facial area.

•The most common type (about 80%)of reported tetanus is generalized tetanus .The disease usually presents with a descending pattern.

Diagnosis of Tetanus

Tetanus is suspected upon exposure to Tetanus is suspected upon exposure to a bite or puncture wounda bite or puncture wound

Because Because C. tetaniC. tetani exhibits such exhibits such exquisite sensitivity to oxygen, it is very exquisite sensitivity to oxygen, it is very difficult to recover and/or grow from difficult to recover and/or grow from clinical specimensclinical specimens

As a result, diagnosis is made on the As a result, diagnosis is made on the basis of clinical findings and historybasis of clinical findings and history

Three Objectives of Management of Tetanus

• To provide supportive care until To provide supportive care until the tetanospasmin that is fixed the tetanospasmin that is fixed in tissue has been metabolizedin tissue has been metabolized

• To neutralize circulating toxinTo neutralize circulating toxin

• To remove the source of To remove the source of tetanospasmin.tetanospasmin.

Treatment of Tetanus

Very difficult to treat once symptoms have Very difficult to treat once symptoms have developeddeveloped

Antitoxin is administeredAntitoxin is administered

Muscle relaxantsMuscle relaxants

Supportive therapy (ventilator) Supportive therapy (ventilator) Cleansing of the woundCleansing of the wound

PREVENTIONPREVENTION

Spores are extremely stable,although immersion in boiling water for 15 minutes kills most spores. Exposure to saturated steam under 15 lbs.of pressure for 15-20 minutes at 121°c is highly effective against spores . Sterilization by dry heat is slower than by moist heat (1 -3 hrs at 160 °C),but it is also effective against spores. Ethylene oxide sterilization is also sporocidal.

FumigationFumigation

• Sterilization of operation theatreSterilization of operation theatre

• 500 ml of formaline, 200gms of 500 ml of formaline, 200gms of Pot.permanganate/30 cu.meters of spacePot.permanganate/30 cu.meters of space

• All windows and doors are closed except All windows and doors are closed except oneone

• Fissures between the panels of the doors Fissures between the panels of the doors and windows are closed with adhesive tapeand windows are closed with adhesive tape

• After 12 hours the doors and windows are After 12 hours the doors and windows are opened and the theatre is aired for 24 opened and the theatre is aired for 24 hours before decommissioning ithours before decommissioning it

•Active ImmunizationActive Immunization

•Passive Passive ImmunizationImmunization

•Active and passive Active and passive ImmunizationImmunization

•AntibioticsAntibiotics

• Tetanus toxoid was developed byTetanus toxoid was developed by DescombeyDescombey in 1924,in 1924,

• Tetanus toxoid immunizations were Tetanus toxoid immunizations were used extensively in the armed used extensively in the armed services during World War II.services during World War II.

• Tetanus toxoid consists of aTetanus toxoid consists of a formaldehyde-treated toxin.formaldehyde-treated toxin.

TETANUS TOXOID

• There are two types of toxoid available There are two types of toxoid available ——adsorbed (aluminum salt adsorbed (aluminum salt precipitated)toxoid and fluid toxoidprecipitated)toxoid and fluid toxoid..

• Although the rates of seroconversion are Although the rates of seroconversion are about equal,theabout equal,the adsorbed toxoid is adsorbed toxoid is preferredpreferred because the antitoxin because the antitoxin response reachesresponse reaches higher titershigher titers and isand is longer lastinglonger lasting than that following the than that following the fluid toxoid.fluid toxoid.

TETANUS TOXOID

ACTIVE IMMUNIZATION

• 11stst dose - 6 dose - 6thth week (DPT) week (DPT)

• 22ndnd dose - 10 dose - 10thth week (DPT) week (DPT)

• 33rdrd dose - 14 dose - 14thth week (DPT) week (DPT)

• 11stst booster - 18 booster - 18thth month (DPT) month (DPT)

• 22ndnd booster - 6 booster - 6thth year (DT) year (DT)

• 33rdrd booster - 10 booster - 10thth year (TT) year (TT)

PASSIVE IMMUNIZATION

1. ATS(equine) Ig- 1500 IU/s.c 1. ATS(equine) Ig- 1500 IU/s.c after sensitivity test after sensitivity test

(or)(or)

2. ATS(human) Ig- 250-500 IU, 2. ATS(human) Ig- 250-500 IU, no anaphylactic shock, very no anaphylactic shock, very safe and costly.safe and costly.

Immunization requires at least three doses of Td.

1st dose should be administered on the First visit

2nd dose 4 – 8 weeks after the first dose of Td and

3rd dose after 6 months of the second Td. A booster dose of Td should be repeated every 10 years throughout life

Persons Seven Years of Age or Older Who Have Not Been Immunized

Treatment of Tetanus Treatment of Tetanus (cont’d)(cont’d)

If recovery does occur, there are If recovery does occur, there are usually no long-term side effects.usually no long-term side effects.

Recovered individuals do not Recovered individuals do not necessarily develop “natural necessarily develop “natural Immunity” against the infection---Immunity” against the infection---because the very small amount of because the very small amount of tetanus toxin produced during the tetanus toxin produced during the infection does not elicit a strong, infection does not elicit a strong, protective immune response which protective immune response which would produce enough antibodies would produce enough antibodies against future re-infectionagainst future re-infection

Photo Courtesy of U.S. Centers for Disease Control and Prevention

Newborn showing risus sardonicus and generalized spasticity

•Maternal tetanus, defined as tetanus occurring during pregnancy or within 6 weeks after any type of pregnancy termination, is one of the most easily preventable causes of maternal mortality.

•It includes postpartum or puerperal tetanus

(i) postpartum or puerperal tetanus, usually resulting from septic procedures during delivery,

(ii) postabortal tetanus, following septic maneuvers during induced abortion

(iii) Tetanus during pregnancy, generally resulting from inoculation through a nongenital

portal of entry

• Neonatal tetanus (NNT), a disease preventable by immunization, is a major problem and a leading cause of neonatal mortality.

•It is easily preventable by 2 tetanus toxoid injections and ‘5 cleans’ while conducting deliveries.

2 major programs are in operation for the prevention of NNT in the country –

•the immunization of pregnant women with tetanus toxoid vaccine (TT) under the expanded program on immunization (EPI)

•The training of dais under the rural health program.

• NNT will be prevented if the women NNT will be prevented if the women and the dais (who are still associated and the dais (who are still associated with almost 70-75% of the deliveries with almost 70-75% of the deliveries in many areas with high NNT in many areas with high NNT mortality rates) are convinced of the mortality rates) are convinced of the need for TT vaccination during the need for TT vaccination during the antenatal period and practice the antenatal period and practice the basic principles of cutting cord and basic principles of cutting cord and keeping the umbilical stump free of keeping the umbilical stump free of unclean dressings. unclean dressings.

Elimination of Neo natal Elimination of Neo natal tetanustetanus1.1. High risk district:High risk district: a) Neo natal death rate > 1/1000 live births a) Neo natal death rate > 1/1000 live births b) 2 doses of tetanus toxoid coverage < 70% b) 2 doses of tetanus toxoid coverage < 70% c) Deliveries attended by trained dais < 50%c) Deliveries attended by trained dais < 50%

2.2. Medium risk districtMedium risk district::

a) Neo natal death rate < 1 / 1000 live birthsa) Neo natal death rate < 1 / 1000 live births b) 2 doses of tetanus toxoid coverage> 70% b) 2 doses of tetanus toxoid coverage> 70% c) Deliveries attended by dais > 50%c) Deliveries attended by dais > 50%

3. 3. Low risk districtLow risk district::

a) NNT <0.1/1000 Live Birtha) NNT <0.1/1000 Live Birth b)b) 2 Doses of T.T Coverage >90%2 Doses of T.T Coverage >90% c) Delivery attended by Trained Dais >75%c) Delivery attended by Trained Dais >75%

PREVENTION OF NEONATAL PREVENTION OF NEONATAL TETANUSTETANUS• 2 doses of T.T to all pregnant women 2 doses of T.T to all pregnant women

betweenbetween 16 to 36 weeks of pregnancy16 to 36 weeks of pregnancy with an interval ofwith an interval of 1 to 2 months1 to 2 months between the two doses.between the two doses.

• The first dose as early as possible & the The first dose as early as possible & the second dose a month later preferablysecond dose a month later preferably 3 3 weeks before delivery.weeks before delivery.

• If the pregnant woman is previously If the pregnant woman is previously immunized,immunized, a booster dosea booster dose is sufficient.is sufficient.

• If the pregnant woman is not If the pregnant woman is not immunized, then the new born should immunized, then the new born should be protected against tetanus by givingbe protected against tetanus by giving tetanus human immunoglobulin 750 IU tetanus human immunoglobulin 750 IU with in 6 hours of birth.with in 6 hours of birth.