Rabies and Tetanus Post Exposure Prophylaxis

Patrick J. Ivory, MPAS, PA-C

Rabies

 Virus transmitted in the saliva of an infected animals     Raccoons, skunks and bats Since 1980- 21 of 36 cases (58%) in humans came from bats In Asia, Africa and Latin America, the majority of cases came fro dogs Even though human rabies is rare, between 16,000 and 39,000 persons received post-exposure prophylaxis. Medical urgency.

Transmission of Rabies Virus

Rabies diagnosis

     History of animal bite or exposure is frequently absent in North America Pain, paresthesia, and pruritis are early neurologic signs of rabies. Probably reflects infection of local ganaglia Autonomic features are common Paralytic features may be prominent – may mimic Guillain-Barre’ Syndrome Saliva samples for RT-PCR and skin biopsy should be obtained for detection of rabies virus antigen

Rabies

  Active immunity – immunization that produces neutralizing antibodies, Thakes 7-10 days to develop and lasts for up to 2 years.

Passive immunity – Rabies Immune Globulin (RIG) provides immediate response – half life 7-10 days

Rabies Vaccines Licensed in the US

    Human Diploid Cell Vaccine (HDCV) Imovax Purified Chick Embryo Cell Vaccine (PCEC) - RabAvert Rabies Vaccine Absorbed (RVA) Rabies Immunogloulin - IgG  BayRabTM and Imogam Rabies-HT

Pre-exposure Rabies Vaccination

 High Risk Groups- Veterinarians, animal handlers, certain lab workers   Post exposure – Eliminates need for RIG Should have booster every 6 months.

Rabies Pre-exposure Sched.

Type of Vaccination Primary Route IM Regimen Booster ID IM ID HDCV, PCEC,RVA 1cc in deltoid days 0,7,21 or 28 HDCV 0.1 cc Days 0,7,21 or 28 HDCV, PCEC,RVA 1 cc on day 0 only HDCV 0.1 cc day 0 only

Rabies Post-exposure Prophylaxis Guide – US 1999 Animal Type Eval and Disposition of animal Postexposure recommendations Dogs, cats, ferrets Skunks, raccoons, foxes, and most carnivores; bats 1.

2.

Healthy and available for 10 observation. Rabid, suspected rabid or unknown Regarded as rabid unless animal proven negative by laboratory testing + 1.

2.

Only if signs of rabies * Immediately vaccinate,. Contact public health officials Consider immediate vaccination Livestock, small rodents, rabbits or hares, large rodents (woodchucks and beavers) and other mammals Consider individually Consult Public Health. Bites of squirrels, hamsters, guinea pigs, gerbils, chipmunks, rats, mice, etc almost never require PEP * During 10 day observation, vaccinate at first sign of rabies, euthanize the animal immediately and test brain. + Euthanize the animal and test ASAP. Holding for observation not recommended. Discontimue vaccination if Immunofluorescence tests are negative

Vaccination status Not Previously Vaccinated Previously Vaccinated Treatment RIG Vaccine Rabies PEP Regimen Wound cleansing Wound cleansing Clean with soap and water. Irrigate with a virucidal agent (povidone-iodine solution) 20IU/kg. Infiltrate entire dose around the wound if possible; if not, inject remainder IM HDCV, RCA or PCEC 1.0 cc IM day 0,3,7,14 and 28 Clean with soap and water. Irrigate with a virucidal agent (povidone-iodine solution) Should not be administered RIG Vaccine HDCV, RCA or PCEC 1.0 cc IM day 0 and 3 These regimens are meant for all age groups. Deltoid area on adults and larger children. Thigh for smaller children. Never buttocks. Day 0 is the day the first dose is administered

Tetanus

 Clostridium Tetani –  Spores tend to be resist to boiling for 20 minutes and to disinfectants    Spores found in animal and human feces.; soil, dust, human dwellings and hospitals Spores grow in areas of low oxygen tension Produces tetanospasmin – one of the most potent neurotoxins – effects peripheral nerves, neuromuscular junctions, muscle, spinal cord, brainstem and possibly the hypothalamus  Rare disease in US; 0.02/100,000 people

Tetanus

 Presentation   Generalized disease –Trismus, dysphagia, isolated cranial nerve palsis, rigidity or stiffness of an extremity, resllessness, tetanic seizures and poor sucking in newnborns Localized Disease – Rigidity in extremity  Cephalic Disease – Single or multiple cranial nerve palsies

Diphtheria

 Bacterial infection – Corynebacterium diphtheriae (Gm. Neg. Rod)   Low incidence in US <0.02/100,000 Last confirmed indigenous case in 1988  Can involved throat, wounds, cardiac muscle and polyneuropathy

Pertussis

   AKA: Whooping cough Caused by Bordetella Pertussis – adheres to human cilia Approx.5000 cases per year   50% in children <1 y/o 20% in children >15 y/o

Pertussis

 Clinical Features   Prodrome like common cold Then increased mucus production   Intense paroxysmal cough which end in gasps and an inspiratory whooping sound Exhaustion and apnea can occur

Immunizations

  Initial – Infants/ children   DTaP 2months, 4months, 6 months, 15-18 months, 4-6 years.

11-18 years Td, with pertussis booster.

  Catch up for children 4 months to 6 years of age  Dose 1; doses 2 in 4 weeks dose 3 in 4 weeks; dose 4 in 6 months and dose 5 in six months.

Catch up for 7 to 18 years. See schedule, varies on how many previous doses received Re-immunization every 10 years unless wound criteria

Wound management

Hx. of absorbed Tetanus Toxoid doses Unknown or less than 3 years Clean, minor wounds Td (t) Yes Three or More No ( § ) TIG No No All other wounds (*) TD (t) TIG Yes Yes No (ii) No (*) Not limited to contaminated with dirt, feces, soil, and saliva; puncture wounds; avulsions; wounds from missiles, crushing, burns and frost bite.

(t) For children <7y/o; DPT is preferred. For persons ≥ Td is preferred ( §) Yes, if >10 years since last dose (ii) Yes, if > 5 years since last dose All adults should have one dose of Td replaced with Tdap.

Tetanus Prophylaxis

 If person had never been vaccinated;   Start the Tetanus/ Diphtheria schedule.

Give Tetanus Immunoglobulin (TIG) – 250 units IM  TIG is not contraindicated in pregnancy  Only protects patient for present injury; does not confer active immunity