rabiesguide3

ONTARIO MINISTRY OF HEALTH AND LONG-TERM CARE

GUIDELINES FOR MANAGEMENT OF SUSPECTED RABIES EXPOSURES

A. Post Exposure Rabies Prophylaxis Guide - Version December, 2005

All suspected incidents must be reported to the local medical officer of health (Health Protection and Promotion Act, Reg. 557, s2 (1))
who can provide consultation and the necessary biologicals.

Exposure Types

Bite exposures are defined as any penetration of the skin by teeth. Note that bites inflicted by bats may not be felt and may leave no visible bite marks. Non-bite exposures include contamination of open wounds, abrasions, mucous membranes, or scratches with saliva or other potentially infectious material such as the brain tissue of a rabid animal. Some exposures may occur in dressing out carcasses.
If the material containing the virus is dry, the virus can be considered non-infectious. Other contact such as petting and contact with blood, urine or feces does not constitute an exposure.

ANIMAL TYPE EVALUATION AND DISPOSITION OF ANIMAL RECOMMENDATIONS FOR POST-EXPOSURE PROPHYLAXIS (PEP)

Dogs, cats, and ferrets Healthy and available for 10 days observation² At first sign of rabies in the animal, begin PEP³

Unknown or escaped Immediately begin PEP, or
Where there is a chance the animal will be found, PEP may be withheld for 48 hrs after exposure³

Rabid or suspected to be rabid⁴ Administer PEP, or
Based on a risk assessment, and where the specimen is received at the lab within 48 hrs of exposure, PEP may be withheld until the FAT⁵
result is available. Discontinue PEP if FAT is negative.

Skunk, bat, fox, coyote, raccoon, and other carnivores.
Includes bat found in room when a person was sleeping unattended or where the person is an infant, child, impaired or mentally challenged and a contact with the bat is difficult/impossible to ascertain.
Regarded as rabid unless test results prove otherwise⁴ Administer PEP, or
Based on a risk assessment, and where the specimen is received at the lab within 48 hrs of exposure, PEP may be withheld until the FAT result is available. Discontinue PEP if FAT is negative.

Livestock, rodents, lagomorphs (rabbits and hares), and other mammals ^6,7
Consider individually. Consult local public health officials. Bites from squirrels, chipmunks, rats, mice, hamsters, gerbils, guinea pigs, other small rodents, rabbits and hares almost never require PEP. PEP may be warranted if the behaviour of the animal was highly unusual.

Notes:

1. Where possible, for all exposures, immediate washing and flushing with soap and water and virucidal agent (e.g., iodine) is imperative.

2. Unwanted animals that cannot be safely isolated and observed may be sacrificed for laboratory examination before the observation period expires.

3. The immediate initiation of PEP should be considered in persons with bites on the face, head, or neck. Consideration should involve a risk assessment.

4. If possible, the animal should be humanely killed and the brain tested for rabies as soon as possible; holding for observation is not recommended.

5. The Fluorescent Antibody Test (FAT) is the laboratory procedure for the diagnosis of animal rabies and the report can be obtained within 6 to 24 hours from receipt of an animal specimen at the laboratory. If the FAT is negative, treatment of the exposed person should be discontinued. If suspicion of rabies in the animal remains high even in the presence of a negative test, PEP should be continued.

6. It is unnecessary to keep a suffering animal alive to ensure an accurate laboratory diagnosis. If an animal has clinical signs of rabies at the time the animal is sacrificed, the virus should be demonstrated in brain tissue by the FAT.

7. Bites inflicted on a person attempting to feed or handle an apprently healthy animal should generally be regarded as provoked.

8. Domestic animals exposed to a rabies confirmed or rabies suspect animal are quarantined under the authority of the Health of Animals Act administered by the Canadian Food Inspection Agency.

B. Recommendations for Post-Exposure Anti-Rabies Treatment

1. Human Diploid Cell Vaccine (HDCV) and Purified Chick Embryo Cell Vaccine (PCEC)

POST EXPOSURE PROPHYLAXIS SHOULD BE STARTED AS SOON AS POSSIBLE AFTER EXPOSURE AND OFFERED TO EXPOSED PERSONS REGARDLESS OF THE ELAPSED INTERVAL. VACCINE SHOULD BE
ADMINISTERED AS WELL AS RABIES IMMUNE GLOBULIN (RIG) EXCEPT IN CERTAIN PREVIOUSLY IMMUNIZED PERSONS AS INDICATED BELOW.

UNDER NO CIRCUMSTANCES SHOULD VACCINE BE ADMINISTERED IN THE SAME SYRINGE OR AT THE SAME SITE AS RIG.

Five doses of vaccine are required ( a single dose is 1 vial of vaccine): the first dose as soon as possible after exposure (day 0), an additional dose on each of days 3, 7, 14 and 28 after the first dose. The vaccine should be given intramuscularly into the deltoid muscle (never in the gluteal region) or in infants the anteriolateral upper thigh. A single dose of RIG is given on day 0 as described below. Routine follow-up antibody determination is not necessary. If the course of vaccine is initiated with one type of vaccine, the other vaccine can be substituted for any of the treatments.

2. Rabies Immune Globulin (RIG)

RIG SHOULD BE ADMINISTERED ON ONE OCCASION, AS SOON AS POSSIBLE AFTER EXPOSURE AND AT THE SAME TIME AS THE FIRST DOSE OF HDCV. If anatomically feasible, the full dose of RIG should be thoroughly infiltrated in the area around and into the wound. The RIG may be diluted 2-3 fold in a solution of 0.9% sodium chloride in order to provide the full amount of RIG required for thorough infiltration of the wound. Any remaining volume should be given intramuscularly using a separate syringe and needle. If the site of the wound is unknown, as in the case of a bat found in a room when a person was sleeping unattended, administer the volume intramuscularly (eg., in the gluteal or lateral thigh area).

Since vaccine-induced antibody begins to appear within one week, there is no value in administering RIG more than 8 days after initiating a course of vaccine. The dosage is 20 I.U. per kilogram or 9.09 I.U. per lb. body weight. RIG is supplied in 2 ml. vials containing (150 IU/ml). Use the following formulae to calculate the dose required:

20 IU/kg x (client wt in kg) ÷ 150 IU/mL = dose in mL
9.09 IU/lb x (client wt in lb) ÷ 150 IU/mL = dose in mL

The guide below can be used to determine the number of vials needed. Do not administer in excess of recommended number of vials. Where the physician is treating more than one patient, the total patient weight should be determined and the appropriate number of vials ordered.

Total Weight		Number of Vials Rabies Immune Globulin
To 33 lbs	15 kg	1
34 - 66 lbs	15 - 30 kg	2
67 - 99 lbs	30 - 45 kg	3
100 - 132 lbs	45 - 60 kg	4
133- 165 lbs	60 - 75 kg	5
166 - 198 lbs	75 - 90 kg	6
199 - 231 lbs	90 - 105 kg	7
232 - 264 lbs	105 - 120 kg	8
265 - 297 lbs	120 - 135 kg	9
298 - 330 lbs	135 - 150 kg	10

3. Post-Exposure Treatment of Previously Immunized Individuals

When an individual is exposed to rabies virus and has been previously immunized with HDCV or PCEC, or they have received a different vaccine and have a demonstrated antibody response (see table in Section 4), that person should receive 2 doses of vaccine, one dose on day 0 and one dose on day 3. DO NOT ADMINISTER RIG.

Where an individual previously received either pre- or post-exposure rabies immunization with a vaccine other than HDCV or PCEC and had not been subsequently tested to demonstrate an antibody response, or whose test was negative, both RIG and 5 doses of HDCV or PCEC should be administered. A serum sample may be taken before vaccine or RIG is given, and if antibody is demonstrated, the course may be discontinued provided at least 2 doses of vaccine have been given.

4. Antibody Determination

Antibody determination has shown to be unnecessary after the fifth dose of vaccine.
Where antibody levels are required, a sample of 5cc whole clotted blood, or serum therefrom, should be submitted to the nearest regional public health laboratory or directly to the Central Public Health Laboratory, 81 Resources Rd., Toronto, Ontario M9P 3T1, Telephone: (416)235-5725. There is no charge for this test. To establish laboratory priority, please indicate the purpose of the sample. (Note if it is to determine the titre following a series of pre- or post-exposure prophylaxis).

This table provides an interpretation of Rapid Focus Flourescent Inhibition Test (RFFIT) neutralizing antibody titres:

IU/ml	Interpretation
< 0.5 IU/ml	Inadequate response
0.5 IU/ml	Minimal potency requirement reflecting adequate response
> 0.5 IU/ml	Satisfactory

For More Information:

www.sanofipasteur.com/canada/products (HDCV/Imovax)
www.rabavert.com (PCEC/RabAvert)
www.rabies.mnr.gov.on.ca/ (Ministry of Natural Resources - rabies in Ontario)
www.cdc.gov/ncidod/diseases/submenus/sub rabies.htm (Centre for Disease Control and Prevention)
www.who.int/rabies (World Health Organization)

References:

Information for these guidelines has been sourced from:
1.    Canadian Immunization Guide (Sixth Edition, Health Canada, 2002)
2.    Control of Communicable Diseases Manual (American Public Health Association, 18th Edition, 2004)
3.    Human Rabies Prevention - United States, 1999. Recommendations of the Advisory Committee on Immunization Practices (Morbidity and Mortality Weekly Report, Centers for Disease Control and Prevention, 1999)

ANIMAL TYPE	EVALUATION AND DISPOSITION OF ANIMAL	RECOMMENDATIONS FOR POST-EXPOSURE PROPHYLAXIS (PEP)
Dogs, cats, and ferrets	Healthy and available for 10 days observation²	At first sign of rabies in the animal, begin PEP³
	Unknown or escaped	Immediately begin PEP, or Where there is a chance the animal will be found, PEP may be withheld for 48 hrs after exposure³
	Rabid or suspected to be rabid⁴	Administer PEP, or Based on a risk assessment, and where the specimen is received at the lab within 48 hrs of exposure, PEP may be withheld until the FAT⁵ result is available. Discontinue PEP if FAT is negative.
Skunk, bat, fox, coyote, raccoon, and other carnivores. Includes bat found in room when a person was sleeping unattended or where the person is an infant, child, impaired or mentally challenged and a contact with the bat is difficult/impossible to ascertain.	Regarded as rabid unless test results prove otherwise⁴	Administer PEP, or Based on a risk assessment, and where the specimen is received at the lab within 48 hrs of exposure, PEP may be withheld until the FAT result is available. Discontinue PEP if FAT is negative.
Livestock, rodents, lagomorphs (rabbits and hares), and other mammals ^6,7	Consider individually.	Consult local public health officials. Bites from squirrels, chipmunks, rats, mice, hamsters, gerbils, guinea pigs, other small rodents, rabbits and hares almost never require PEP. PEP may be warranted if the behaviour of the animal was highly unusual.