RABIES CONTROL & ERADICATION PROGRAM

1. Ninfa R. Ambat, M.D. FPAFP RABIES CONTROL & ERADICATION PROGRAM

2. RABIES RNA virus; SS RNA approx. 75-80 nm diameter Bullet-shaped, enveloped Rhabdovirus group Acute viral disease of the CNS that affects all mammals Acute encephalitis: fatal outcome, no effective cure

3. WHO Ranks 12th among major killer diseases. Around 10 million people are exposed annually.

4. EPIDEMIOLOGY Philippines: endemic disease despite availability of vaccines 6-8 / million population (one of the highest worldwide) Locally: approx. 400,000 people consult for rabies exposure annually (75% post-exposure vaccination) Domestic dog: 98% of human rabies

5. PATHOGENESIS & CLIN. MANIFESTATIONS Incubation period: 20-90 days; > 95% of patients will (+) with S/Sx within 6 months of exposure Virus remains at site of bite, undergoes amplification; crosses the myoneural junction to reach the nerve ending.

6. PATHOGENESIS (Incubation Period) Patient has no symptoms except those related to local wound healing. No lab tests available which can diagnose rabies. THE ONLY TIME WHEN VACCINATION IS EFFECTIVE!

7. PATHOGENESIS (Prodrome) 2-10 days Virus reaches the spinal cord Non-specific S/Sx: fever, headache, body malaise 1st rabies specific sx: pain or itching or paresthesia at bite site.

8. PATHOGENESIS (Acute Neurologic Phase) 2-7 days Virus reaches the brain, multiplies & disseminates rapidly to the rest of the organs notably the SALIVARY GLANDS. Patient may die at this stage. May present in 2 ways:

9. Encephalitic or “Furious” Rabies 80% of cases. Hyperactive episodes: combative, (+) bizarre behavior, agitated or apprehensive, alternating with lucid moments HYDROPHOBIA: elicited by giving the px a glass of H2O, (+) rxn: agitation, cringing, contraction of muscles; caused by painful contractions of laryngeal muscles upon drinking. AEROPHOBIA: elicited by fanning the patient; (+) rxn same as above.

10. Paralytic or “Dumb” Rabies In 20% of cases. Starts as paralysis of the bitten area which spreads to involve all limbs & eventually ends in respiratory paralysis. Most often missed: hydrophobia and aerophobia are absent. High index of suspicion: pxs who came in with paralysis or encephalitis of undetermined etiology. A hx of prior exposure should be elicited.

11. PATHOGENESIS (Coma) 4-10 days. Complications start to appear. Outcome: DEATH due to respiratory paralysis!!!

12. DIAGNOSIS Made clinically Pathognomonic hydrophobia and aerophobia with history of exposure = DIAGNOSIS OF RABIES

13. LABORATORY WORK-UP RT-PCR of saliva / oral swab Corneal imprint (FAT) CSF exam: increase in mononuclear cells, proteins are slightly elevated Post mortem samples: (+) for FLUORESCENT ANTIBODIES TEST, done in dogs

14. MANAGEMENT Therapy Mortality rate almost 100% Better prevented than treated Specific chemotherapy for rabies is not available Supportive care: IVF and sedation (midazolam & diazepam)

15. PRECAUTIONS IN HANDLING RABID PATIENTS Rabies is communicable; a suspected case requires immediate isolation. Px should be restrained. Anyone coming in direct contact with the px must wear gloves, face mask, gown & goggles. Special attention should be paid to the px’s saliva, sputum, CSF & other body secretions & to the disposal of equipment that may harbor rabies virus such as foley & suction catheters.

16. PRECAUTIONS IN HANDLING RABID PATIENTS Equipment used should be sterilized at 600C for at least 30 min to kill the virus. Immediate hand washing with soap & water is necessary after handling the patient or his body secretions. These precautions should be undertaken during the entire duration of the illness.

17. MANAGEMENT: Requires prophylaxis Bites with penetration of skin. Exposure to px’s saliva or other potentially infectious material in direct contact with mucus membrane (oral, conjunctival or genital) or broken skin (cut, scratch, abrasion). Scalpel nicks or needle stick injuries if these were in contact with CSF, nervous tissue, ocular tissue or internal organs.

18. No prophylaxis necessary Contact with blood, stool Contact with potentially infectious material in direct contact with intact skin. Needle stick injuries where the needle came in contact with blood only. Sharing of food/drink with px. Casual contact such as hx taking, PE, being in the same room.

19. Category I Category II Category III Prophylaxis should be given depending on the category of exposure:

20. Category I Includes sharing of food/drink with rabid px; casual contact. No prophylaxis is required but may give pre-exposure prophylaxis (D0, D7, D28) if desired.

21. Category II Includes licking of broken skin; superficial bites without bleeding. Give vaccine only.

22. Category III Bites which bleed. Splashing or splattering of saliva or CSF or other infectious body fluids into eyes/mouth. Scalpel nicks or needle stick injuries where the needle is in contact with CSF, nervous tissue, ocular tissue, internal organs, saliva or other infectious body fluids.

23. Category III Requires: Vaccine Rabies immune globulin (RIG)

24. Pre-exposure Prophylaxis Those who are at high risk: Veterinarians Animal handlers Lab workers Hospital staff (attending to rabid pxs)

25. Regimens PVRV (0.5 mL) or PDEV (1.0 mL) IM at 1 site on days 0, 7 and 28. PVRV (0.1 mL) or PDEV (0.2 mL) at 1 site on days 0, 7 and 28. Booster dose (every 1-3 years) is required for those with continuing risk. PVRV: Purified Vero Cell Rabies Vaccine PDEV: Purified Duck Embryo Vaccine

26. Post Exposure Treatment General Principles: To minimize the amount of virus at the site of inoculation. T develop a high titer of neutralizing antibody early & maintain it for as long as possible.

27. Components of Post-exposure Treatment Local Wound Care Immediate vigorous washing & flushing with soap & H2O, detergent or H2O alone are imperative Apply alcohol, tincture or aqueous solution of iodine or povidone iodine. Anti-tetanus prophylaxis should be initiated or boosted (check immunization history). Animal bite wounds are considered tetanus prone.

28. Components of Post-exposure Treatment Local wound care Suturing of wounds should be avoided or delayed as it may inoculate virus deeper into the wound. If suturing is unavoidable (e.g. deep face wounds) it should be done loosely. Make sure RIG is instilled deep into the wounds before suturing.

29. Components of Post-exposure Treatment Local wound care Antibiotic Prophylaxis Administer prophylactic abx to all Category III dog bites that are either deep, penetrating, multiple or extensive. For these instances where there are no signs of infection, amoxicillin as prophylaxis may be suffice.

30. Components of Post-exposure Treatment Local wound care Antibiotic Prophylaxis For frankly infected wounds, may give either cloxacillin or co-amoxiclav. Other exposures (Category I or II) may be given abx only if the wound is infected.

31. Components of Post-exposure Treatment Passive Immunization (Ig) Equine Rabies Immune Globulin (ERIG): 40 units/kg on Day 0 ANST; as much of the recommended dose as anatomically feasible should be infiltrated around the wound(s); the rest is given IM on the gluteal region.

32. Components of Post-exposure Treatment Passive Immunization (Ig) Human Rabies Immune Globulin (HRIG): 20 units/kg on Day 0; as much of the dose should be infiltrated around the wound, the rest given IM on the gluteal region. NOTE: HRIG is given if skin test to ERIG is (+), or with previous hx of rxn to an equine serum.

33. Components of Post-exposure Treatment Active Immunization Should be given on the deltoid muscle (adults) & on the anterolateral thigh (young infants). Purified Vero Cell rabies Vaccine (PVRV) 0.1 mL or Purified Duck Embryo Vaccine (PDEV) 0.2 mL intradermally @ 2 sites on days 0, 3, 7 and 1 site on days 30 and 90.

34. Handling of the Biting Animal Animal is healthy at the time of bite Observe for 14 days from time of incident. Don’t sacrifice healthy animal. Restricted to one area (caged/leashed). Examined by a vet on the last day. No signs of rabies  free from rabies.

35. Handling of the Biting Animal Animal is sick at time of bite But no signs of indicative rabies, have it confined by a vet.

36. Handling of the Biting Animal S/Sx at the time of bite during observation period, call AP sudden change in behavior (from mild to vicious temperament or vice-versa) characteristic hoarse howl watchful, apprehensive expression of the eyes, staring, blank gaze drooling of saliva paralysis or uncoordinated gait marked excitability and restlessness; pacing in cage if restrained, attacks objects within range, bites cat

37. Handling of the Biting Animal S/Sx at the time of bite during observation period, call AP (cont.) if at large, runs aimlessly, biting anything in its way depraved appetite, self-mutilation in some cases, lies quiescent, biting when provoked snaps at imaginary objects paralysis of lower jaw & tongue; inbility to drink sudden death without assoc’d s/sx

38. Handling of the Biting Animal Rabid animal sacrificed danger to the public avoid damaging the head Sacrificed animal rabies diagnosis

39. National Rabies Control General Objectives To eradicate rabies & thereby declare a rabies free Philippines

40. National Rabies Control Specific Objectives To control human & canine rabies in confirmed endemic areas To prevent spread of rabies to non-endemic rabies areas To areas establish a mechanism for a Quick-Response Canine Immunization Program To segmentally declare rabies free zones

41. ANIMAL BITE CENTERS… DLSUMC Emergency Room & OPD Rural Health Units of municipalities Gen. Emilio Aguinaldo Memorial Hospital, Trece Martires City RITM, Alabang, Muntinlupa

42. Canine Rabies Prevention Mass immunization Dog control movement Dog registration Compulsory leashing Stray dog control Rabies diagnosis & surveillance Reduction of contact rates between susceptible dogs Mobilization of community participation

43. THANK YOU!