STATION 1 – Rabies vaccine 1. Incubation period of Rabies 2. Mortality rate in rabies 3. Currently available vaccines for rabies 4. Diluent used in rabies vaccine 5. Shelf life in rabies vaccine
Incubation period averages 4-6 weeks but can range from five days to 6 years. The disease is uniformly fatal and only 6 survivors have been reported in world literature. The currently available vaccines are the modern tissue culture vaccines (MTCV) and include Purified Chick Embryo Cell (PCEC) vaccine, Purified Duck Embryo Vaccine (PDEV), Human Diploid Cell Vaccine (HDCV), Purified Vero Cell Vaccine (PVRV). The vaccines are available in lyophilized form with sterile water as diluent. Stable for 3 years at 2 to 8°C and should be used within 6 hours of reconstitution.
Station 2 – Rabies IG 1. Types & doses of RIG 2. Indication of RIG & method of administration 3. Role of RIG in a child who presents on day 14 of getting rabies vaccine. 4. Role of RIG in a person who has received post exposure prophylaxis in the past.
2 types of RIG: (1) Human rabies immunoglobulin (HRIG – dose is 20 U/kg body weight, maximum dose 1500 IU) and (2) Equine rabies immunoglobulin (ERIG – dose is 40 U/kg body weight, maximum dose 3000 IU). RIG is indicated in all cases of category 3 wounds where it should be infiltrated thoroughly into and around the wound. The remaining part if any is to be injected IM into the deltoid region or anterolateral aspect of thigh away from the site of vaccine administration. If RIG could not be given when antirabies vaccination was began, it should be administered as early as possible but no later than the seventh day after the first dose of vaccine was given. From the eight day onwards, RIG is not indicated since an antibody response to the vaccine is presumed to have occurred. RIG is also not indicated in individuals who have received pre exposure prophylaxis/ post exposure prophylaxis in the past.
Station 3 - Rabies Steps to be followed in the management of a case of stray dog bite.
1.Thorough cleansing of wound with soap and flushing under running water for 10 minutes. 2.Followed by irrigation with virucidal agent - 70% alcohol or povidone iodine. 3.Antimicrobials & tetanus toxoid if indicated. 4.RIG should be infiltrated in & around wound in category 3 bites. 5.Suturing of wound should be avoided. When suturing is unavoidable for purpose of hemostasis, it must be ensured that RIG has been infiltrated in the wound prior to suturing.
6.All category 2 and 3 bites merit rabies vaccine. 7.Given intramuscularly in anterolateral thigh or the deltoid. Rabies vaccine should never be injected in the gluteal region. 8.Dose is same at all ages & is 1 ml IM for HDCV, PCEV, PDEV and 0.5 ml for PVRV. 9. Standard schedule (Essen protocol) is five doses on days 0, 3, 7, 14 and 30, with day ‘0’ being the day of commencement of vaccination. A sixth dose on day 90 is optional (for patients with severe debility or immunosuppressed.) 10. If the animal remains healthy over a 10 day observation period, further vaccination may be discontinued. It is however desirable to administer one more dose on day 28 in order to convert to the pre exposure prophylaxis schedule.
Station 4 - Rabies 1. A person who was bitten by a stray dog comes to you 6 months later. He hasn’t received rabies vaccine or RIG. He hasn’t seen the dog since then. What would you suggest? 2.Write down the WHO categories of Rabies exposure, and management in brief.
Persons presenting several days/ months/ years after the bite should be managed in a similar manner as a person who has been bitten recently (with RIG if indicated) as rabies may have a long incubation period. .
Station 5 – ID Rabies vaccine 1. Advantages of ID Rabies vaccine 2. Common approved ID schedules 3. Types of vaccines approved for ID use 4. ID route is not to be used in?
Intradermal vaccination is cost effective alternative to intramuscular vaccination as the dose required is only 0.1 ml. Thai Red Cross Regimen Updated Thai Red Cross Regimen Vaccines currently recommended for ID route in India are purified vero cell rabies vaccine & purified chick embryo cell vaccine. Intradermal route should not be used for immunocompromised patients & those on chloroquine therapy.
Station 6 – Pre exposure Prophylaxis 1. Schedule of Pre-exposure prophylaxis in rabies. 2. Role of monitoring anti-rabies antibody titre. 3. Re-exposure prophylaxis in a person who has already received prophylaxis in the past.
Three doses are given intramuscularly in deltoid/ anterolateral thigh on days 0, 7 and 28 (day 21 may be used if time is limited but day 28 preferred). Routine assessment of anti rabies antibody titer after completion of vaccination is not recommended unless immunocompromised. It is desirable to monitor antibody titers every 6 months in those with continuous exposure and every year in those with frequent exposure. A booster is recommended if antibody levels fall below 0.5 IU/ml. For re exposure at any point of time after completed (and documented) pre or post exposure prophylaxis, two doses are given on days 0 and 3. RIG should not be used as it may inhibit the relative strength or rapidity of an expected anamnestic response.