Intradermal Rabies Vaccination Research Articles

Comparing Intradermal (ID) Rabies Vaccination with Conventional IM Regimen on Humoral Response of New Zealand White Rabbits for the Production of Animal-Derived Polyclonal Antibodies.

In developing countries, it is imperative to implement cost-effective strategies for animal humoral response development in the production of antiserum. This study compared the effect of immunization regimens on the humoral immune response of New Zealand White (NZW) rabbits (N = 24) using cell culture rabies vaccine (CCRV) through intradermal (ID) and traditional intramuscular (IM) routes. The rabbits were divided into three experimental groups: (a) IPC-R2 with a two-site one-week regimen; (b) TRC-R3 with a two-site twenty-eight-day regimen; and (c) Alternate-R4 with a four-site one-week regimen. These regimens were then compared to the standard IM schedule of five doses of rabies vaccine administered at days 0, 3, 7, 14, and 28 in control group R-1. The results were evaluated at days 14 and 35 postvaccination using rabies-specific Platelia II™ ELISA kit method. The results showed a better response to the ID regimen than the IM route regarding immunogenicity and volume consumption of the vaccine. The three selected ID regimes showed significantly higher mean titer values than the control IM regimen group R-1 (p < 0.001). The study aims to explore simple immunization strategies to enhance the RV-specific antibody titers for immunization donor animals. This method would produce polyclonal antibodies and strengthen local production of polyclonal antibodies in Pakistan to deal with vaccine and rabies immunoglobulin (RIG) shortage, thus providing effective postexposure prophylaxis (PEP) for better control of rabies in developing countries.

Survival of 21 Dogs after Post-exposure Prophylaxis using Intra-dermal Rabies Vaccine in the Pre-scapular Region and Emergency Use of Expired Equine Rabies Immunoglobulin for Local Wound Infiltration in Victims of a Rabid Dog Bite using One Health Approach

Rabies is a 100% fatal zoonotic disease and is preventable through timely and adequate Post-Exposure Prophylaxis (PEP). World Organization for Animal Health (WOAH) haven’t issued any guidelines for PEP for rabies in animals, still in certain Indian states like Himachal Pradesh (HP) PEP regimen with active immunization on 0,3,7,14 and 28 days mostly by Intramuscular Rabies Vaccine (IMRV) is being followed. Recently in Rampur Bushahar, a suspected rabid dog later laboratory confirmed had bitten 21 dogs, 2 cows, and 2 men. We employed PEP in animals using Raksharab vaccine intra-dermally (IDRV) (0.2 ml, pre-scapular region) on days 0, 3,7,14, and 28 along with only local wound infiltration of eRIG in 8 out of 11 bitten dogs with Category III exposure. Furthermore, 3 noncooperative dogs with Category III exposure were given IMRV (1ml) on day 0,3,7,14,28 with only wound infiltration of eRIG. 2 Cows were administered 0.2 ml IDRV in the skin at the middle of the neck with only wound infiltration of eRIG. Human bite victims also received 0.1 ml IDRV at 2 sites in the deltoid region on days 0,3, and 7 along with wound infiltration of eRIG at the nearby health center. Serum samples were collected for Rapid Fluorescent Focus Inhibition Test (RFFIT) for estimation of Rabies Vaccine Neutralizing Antibody (RVNA) titer after day 14 for 8 dogs, 2 cows, and human bite victims, and all had RVNA titer &gt;0.5 IU/ml on day 14 except one in IMRV group. None of the bitten victims had clinical manifestations of rabies even after 1 year of follow-up. This indicates wound infiltration with eRIG along with the vaccine could be a life-saving protocol. Also using expired eRIG in emergencies was safe and life saving in animals. Expired eRIG used was later tested and was found to be potent.

Long-term persistence of antibodies and boostability after rabies intradermal pre-exposure prophylaxis.

Currently, there is limited data on long-term persistence of antibodies and boostability of intradermal (ID) rabies pre-exposure prophylaxis (PrEP) schedules. This study investigated travellers who received a primary ID PrEP schedule at least 5years previously to determine the persistence of antibodies and subsequent antibody response after one 0.1-ml ID booster dose. Adults (age ≥ 18years) who had previously received ID PrEP at a specialist travel medicine clinic in Brisbane, Australia were included. At Day 0, blood was collected for serology and one dose of 0.1-ml ID rabies vaccine (Verorab®) was administered. At Day 7, serology was repeated. At Day 14, participants were given results and enquired if they experienced adverse events following immunization (AEFIs). Antibodies were measured using Platelia Rabies II ELISA; levels ≥0.5 EU/mL were considered antibody-positive. 158 participants were included [64.6% female, median age at enrolment 56.4years, interquartile range (IQR) 42.4-65.2years], and median time since the primary ID PrEP was 8.5years (IQR 6.9-11.7years). The majority of participants (82.3%) were antibody-positive at Day 0. The proportion of participants who were antibody-positive at Day 0 was higher among those who were younger at primary vaccination (87.0% if aged<50years, 75.8% of aged ≥50years). The proportion of participants who were antibody-positive declined as median time since primary vaccination increased, though the trend was not statistically significant (p-trend = 0.187). All except one participant (99.4%) were antibody-positive after one ID booster dose. AEFIs were reported by 42.4% of participants and were mainly mild. Rabies antibodies persist for many years after ID PrEP and can be rapidly boosted with a single ID dose. Future studies are needed to confirm that ID PrEP primes the immune system sufficiently so that boosters are not routinely needed, and only given in the event of a rabies-prone exposure.

A randomized clinical trial to assess the immunogenicity of a single-visit four-dose intradermal booster rabies regimen with topical imiquimod

Background: Two-visit intradermal pre-exposure rabies vaccination schedules (PrEP) are now advised by the WHO. Moreover, a double-dose single-visit intradermal 12ID PrEP schedule showed robust immune responses following four-dose or double-dose single-visit intradermal post-exposure prophylaxis (14ID or 12ID PEP) (Soentjens P et al. Clin Infect Dis Aug 2019). Such accelerated 1-visit schedules for PrEP and PEP at very low cost are very practical. Methods and materials: Aim. To investigate the additional effect of the topical pre-administration of imiquimod (IMIQ) (during 1-visit intradermal PrEP) on the neutralizing antibody responses after a four-dose 1-visit intradermal booster schedule. Methods. Belgian soldiers (N = 268) were vaccinated with a 12ID PrEP schedule and boosted with a 14ID PEP schedule, using the Purified Chicken Embryo Cell Vaccine (PCECV). In this study (EudraCT 2017-002953-12), subjects were randomized (during PrEP) for the topical treatment with IMIQ versus placebo cream, as well as for the use of an intradermal device (VAX-ID™) versus routine intradermal syringe. We investigated the serological responses, by rabies fluorescent focus inhibition test (RFFIT) on day 7, after 14ID PrEP in the four treatment groups for 162 of the 268 subjects. A titer ≥3.0 IU/ml is considered to be a strong and adequate antibody response. Results: Median age was 23.5 (IQR 22.7–24.7). 83% were male. Timing between PrEP and PEP was 1.13 years (IQR 1.13–1.13). The GMT of RFFIT on day 7 after 14ID PEP was 19.42 IU/mL (CI 12.43–30.35). 92.3% of the 52 subjects had a RFFIT ≥0.5 IU/mL at day 7 of which 88,5% a level >3.0 IU/mL and 83% >10.0 IU/mL, following 12ID PrEP. The GMT (2 groups comparison) of RFFIT on day 7 after 14ID by intervention groups was 20.20 (10.58–38.57) and 18.66 (9.63–36.15) for the IMIQ versus placebo group respectively, and 18.09 (8.39–39.00) and 20.84 (12.47–34.85) for the VAX-ID versus needle group respectively. Conclusion: Good anamnestic booster responses following 14ID PEP, one year after 12ID PrEP, were recorded. This powered clinical data, in addition with the data of 12ID PrEP by Soentjens et al., proofs that the concept of single-visit priming and single-visit boosting (PrEP and PEP) is very promising and deserves more promotion.

Factors influencing the immune response after a single-dose 3-visit pre-exposure rabies intradermal vaccination schedule: A retrospective multivariate analysis

BackgroundThe World Health Organization (WHO) recommends intradermal (ID) rabies vaccination as a safe and immunogenic alternative to intramuscular administration. The aim of this study is to determine which factors influence the levels of rabies virus neutralizing antibodies (RVNA) after a 3-visit ID rabies vaccination. MethodsThis is a retrospective secondary data analysis study based on electronic health record vaccination data of Belgian military subjects who received ID rabies Pre-exposure prophylaxis (PrEP) with a single-dose 3-visit regimen during the period 2014–2017. Logistic regression was performed to identify predictive factors of RVNA level ≥3.0 IU/mL and >10 IU/mL. ResultsThe second analysis performed on the 2025 subjects (100% seroconverted with a RVNA ≥ 0.5 IU/mL) shows a significantly better immune response in subjects younger than 30 years compared to all other age-groups, a gender-difference to predict RVNA ≥ 3.0 IU/mL (OR 2.30 [1.26–4.22] comparing “female” to “male”) and the influence of the vaccination schedule (OR 2.28 [1.15–4.53] comparing “late - very variable” to “correct” schedule) to predict > 10 IU/ml. Multivariate analysis also demonstrates that a postponed serology control significantly influences the Rapid Fluorescent Focus Inhibition Test (RFFIT). ConclusionGender and age significantly influence the response to ID rabies vaccine. Timing of RVNA determination is important to correctly assess the response to vaccination. A single-dose 3-visit ID rabies PrEP schedule is a dose-sparing effective alternative to the double-dose 2-visit ID schedule. When the minimum time interval between doses is respected, RVNA determination is not necessary.

Single-visit, 4-site intradermal (ID) rabies vaccination induces robust immune responses 5 years after 1-week, 4-site ID primary post-exposure prophylaxis in the Philippines

BackgroundIn a randomized controlled study (NCT01622062) a 1-week, 4-site intradermal (ID, 4-4-4-0-0) post-exposure prophylaxis (PEP) rabies vaccination regimen with purified Vero cell rabies vaccine (PVRV, Verorab®, Sanofi Pasteur), either without (Group 1) or with (Group 2) purified equine rabies immunoglobulin (ERIG), patients in the Philippines achieved seroconversion rates at Day 14 that were non-inferior to that of the updated Thai Red Cross (TRC) 28-day, 2-site (2-2-2-0-2) ID regimen with ERIG (Group 3). Presented here are the annual immunogenicity data up to five years after the last primary dose, and the immunogenicity and safety data following simulated PEP with single-visit, 4-site ID regimen. MethodsRabies virus neutralizing antibodies (RVNA) were determined by rapid fluorescent focus inhibition test (RFFIT). Participants (n = 397) received simulated PEP vaccination ID at Year 5 and RVNAs were assessed at Day 11 post-vaccination. ResultsSeroconversion rates (RVNA titres ≥ 0.5 IU/mL) during annual follow-up remained >95% in Group 1 and were relatively stable at 80–90% in Group 2, but decreased from 80% to 64% in Group 3. RVNA geometric mean titres (GMTs) in Group 1 were consistently higher than in the other two groups, and those in Group 3 were generally lower than in the other two groups. There was a clear anamnestic response to vaccination in all groups, with all participants achieving RVNA titres ≥ 0.5 IU/mL at Day 11 post-simulated PEP booster vaccination. There were no safety concerns raised during annual follow-up and with simulated post-exposure vaccination with PVRV. ConclusionThe shortened, 1-week, 4-site ID regimen with PVRV achieved persistently higher RVNA titres than the updated 2-site TRC regimen, and more participants remained seroprotected up to five years after the last dose of primary immunization. Simulated post-exposure with 4-site ID rapidly induced an anamnestic response indicative of robust protection.

Intradermal rabies vaccination: An efficient and economical method of rabies prevention in cattle

Intradermal rabies vaccination: An efficient and economical method of rabies prevention in cattle

Effect of Antimalarial Drugs on the Immune Response to Intramuscular Rabies Vaccination Using a Postexposure Prophylaxis Regimen.

Chloroquine can impair the immune responses to intradermal rabies vaccination. Current guidelines recommend an extra intramuscular dose be given for postexposure prophylaxis in previously unvaccinated persons taking any antimalarial drug. We conducted a randomized, open-label, single-site study in 103 previously unvaccinated healthy adults age ≥18 to ≤60 years old to evaluate the effects of chloroquine, atovaquone/proguanil (Malarone), and doxycycline on the antibody response to a purified chick embryo cell vaccine, given on a postexposure prophylaxis schedule. All treatment groups received antimalarials 14 days prior to and during vaccination. All subjects achieved accepted neutralizing antibody titers of ≥0.5 IU/mL following the second rabies vaccination dose and maintained this protection through the duration of the study. We observed a reduction in rabies antibody geometric mean titer in the chloroquine versus control groups 28 days after vaccination: 2.3 versus 6.87 IU/mL, respectively (P < .001, t test). A significant difference was not observed for those taking Malarone or doxycycline. We conclude that there is no reduction of rabies antibody response in subjects taking Malarone or doxycycline, but a significant reduction in those taking chloroquine; however, accepted antibody levels were achieved for all 3 antimalarials. NCT02564471.

Simplification of Rabies Postexposure Prophylaxis: A New 2-Visit Intradermal Vaccine Regimen.

.A 2-visit multiple-site intradermal (ID) vaccine protocol would be the most economical, immunogenic, and practicable regimen for postexposure rabies prophylaxis (PEP) in clinics seeing few patients a month. This regimen with an additional day 28 dose is now recommended by the WHO. The difficulties surrounding ID rabies vaccination have hindered progress in provision of prophylaxis, especially in rural Asia and Africa. Although the latest WHO recommendations include 1-week ID postexposure vaccine regimens, these are unlikely to prove economical where rabies vaccination is presently unavailable. The new protocol uses a whole vial of vaccine divided between 4-sites ID on the first day and half a vial at 2-sites ID on day 7. Gavi has recently approved support for rabies PEP. This 2-visit 4-site ID regimen, with or without a day 28 dose, should be considered for implementation in this remarkable new initiative.

Timing of Intradermal Rabies Pre-exposure Prophylaxis Injections: Immunological Effect on Vaccination Response.

Rabies remains a global threat, with annually over 59,000 deaths. Intradermal (ID) pre-exposure prophylaxis (PrEP) is very efficient and reduces the need for rabies immunoglobulins. Not much is known about factors that influence the immune response to ID administered rabies vaccine. The aim of this study is to determine if variations in timing of vaccine administration and serology determination, age and gender have an influence on the levels of rabies virus neutralizing antibody (RVNA) after ID rabies vaccination. This is a retrospective study based on electronic health record vaccination data of Belgian military personnel who received ID rabies PrEP with a three injections regimen during the period 2014-2017. Serology was determined by using the RFFIT method. Fischer's exacts tests were used to evaluate the effect of each independent variable on RVNA levels. In this study, 2,112 subjects were included. All but one seroconverted with a RVNA level ≥0.5 IU/mL. About 48% of subjects developed an antibody titer of >10 IU/mL, 36% had antibody levels 3-10 IU/mL and 16% had an antibody level 0.5-2.99 IU/mL. Statistically significant (p = 0.0018) higher RVNA levels are observed in the groups that received vaccination doses later as planned. Timing of serology determination also influenced RVNA levels significantly (p = 0.000). Antibody levels were significantly higher in females than in males (p = 0.000). Age did influence RVNA levels significantly (p = 0.022). Timing of vaccine dose administration, timing of serology testing, sex and age do significantly influence the humoral B-cell response to ID administered rabies vaccine.

Post exposure compliance of rabies vaccination among cases attending anti-rabies clinic at tertiary care centre, Rajasthan

Background: Rabies is one of the deadliest diseases of mankind, and has terrified since antiquity. It is 100 per cent fatal, however, 100% preventable. In India, rabies causes an estimated 20,565 deaths with 17.4 million exposures to animal bites, mainly dog bites, occurring every year. In India a person is bitten by an animal in every 2 seconds and someone dies from rabies every 30 second. Complete post-exposure prophylaxis is necessary among the animal bite cases for complete protection. Hence this study aims to determine the patient’s compliance for intradermal anti-rabies vaccination and also to determine the constraints for compliance.Methods: A retrospective record based study was conducted in the ARC of S.M.S.M.C, Jaipur where patients were provided intradermal rabies vaccination (updated Thai Red Cross regimen) for post-exposure prophylaxis. The records maintained at ARC-SMSMC under department of community medicine from March 2016- February 2017 were analysed. The total number of patients was 8873 from which 8590 subjects were recruited for the study after excluding category I cases, pre-exposure cases rat bite, human bite, re-exposure and pre-exposure cases. The major constraints were found out by interviewing the patient/guardian through the telephone.Results: The compliance rate for intradermal rabies vaccination (IDRV) is 81.87%. The major constraints were timings not convenient, personal or social workload, long distance from the hospital, forgotten the dates.Conclusions: The compliance rate for rabies vaccination is considerably low for this highly fatal disease. Considering these major constraint factors, the animal bite victims should be motivated effectively through health education at the time of initiation of vaccination course to attain the goal of rabies free India.

Profile of animal bite victims reporting to intradermal rabies vaccination centre at a tertiary care government hospital: 10 years experience

Background: Rabies is acute, progressive encephalitis caused by a lyssavirus. Over 95% of rabies deaths in humans result from virus transmission through the bites of infected dogs. To provide Post Exposure Prophylaxis to the people, Anti Rabies Clinics have been established in many places, especially at tertiary care centres. The Anti-Rabies Clinic at Mandya Institute of Medical Sciences, Mandya, Karnataka state (ARC-MIMS) is one such centre, the first of its kind in Karnataka state more than ten years ago. We are presenting the clinical profile of the animal bite victims who sought treatment at our centre in the past 10 years.Methods: It was a retrospective record based study conducted at Mandya Institute of Medical Sciences with sample size of 44087 using purposive sampling from May 2018 to June 2018 and data was collected using data extraction sheet.Results: Among the 44087 animal bite victims majority i.e., 66.6% were males, most of them were in the age group of 16-60 years. Sixty percent of the animal bite victims were residing in rural areas. All the category 2 and category 3 bite victims were administered anti rabies vaccination and 15.4% of the category 3 bite victims were administered rabies immunoglobulin.Conclusions: Majority of animal bite victims were presented and treated within 1 day. The practice of giving health education periodically to the school children and making phone calls to remind follow up days which is being practiced should be promoted.

Intradermal post-exposure rabies vaccination with purified Vero cell rabies vaccine: Comparison of a one-week, 4-site regimen versus updated Thai Red Cross regimen in a randomized non-inferiority trial in the Philippines

BackgroundRabies post-exposure prophylaxis (PEP) via intradermal (ID) administration is standard practice in Asia. Accumulating evidence suggests that PEP shortened to 3 visits in one week does not adversely affect seroconversion rates or immune memory. ObjectiveTo determine whether the seroconversion rate at Day14 with a 1-week, 4-site (4-4-4-0-0) ID vaccination regimen with or without rabies immunoglobulin (RIG) was non-inferior to the updated Thai Red Cross (TRC) 28-day, 2-site (2-2-2-0-2) ID regimen with RIG during rabies PEP. We also assessed one-year antibody persistence. MethodsThis phase III, mono-center, open-label, randomized-controlled trial assigned participants aged ≤50 years (n = 600) exposed to suspected rabid animals and sustaining WHO Category II injuries (automatic allocation to G1) or Category III injuries (randomized to G2 or G3) to the following groups (1:1:1 ratio): G1 (n = 200), 1-week 4-site ID regimen with the purified Vero cell rabies vaccine (PVRV; Verorab®) without RIG; G2 (n = 201), 1-week 4-site ID regimen with PVRV, and purified equine rabies immunoglobulin (pERIG); G3 (n = 199), TRC 28-day, 2-site ID regimen with PVRV, and pERIG. Non-inferiority tests compared G1 vs. G3 and G2 vs. G3. Seroconversion rate was the proportion (%) of vaccinees with rabies virus neutralizing antibodies (RVNA) titers ≥0.5 IU/mL measured by rapid fluorescent focus inhibition test. ResultsOn Day14, after the third vaccine administration, seroconversion rates were non-inferior in both comparisons and were, respectively, 100%, 99.4%, 98.8% in G1, G2, G3 with a decrease to 97.6%, 89%, 79.8% at Year 1. At Day14, RVNA geometric mean titers were 11.3 IU/mL; 9.89 IU/mL; 6.15 IU/mL, respectively, decreasing to 2.96 IU/mL, 1.37 IU/mL, 0.97 IU/mL at Year1. Safety and tolerability were similar between the three groups. ConclusionThe seroconversion rate at Day 14 with the 1-week 4-site ID regimen, both with and without pERIG, was non-inferior to the reference TRC 28-day 2-site ID regimen with pERIG during rabies PEP with PVRV.ClinicalTrials.gov ID: NCT01622062.

Clinical safety profile of Premi-Rab a new indigenous equine rabies immunoglobulin for cat III animal bite victims at anti rabies clinic of a tertiary care hospital, Karnataka

Background: WHO guidelines recommend for treating Cat III animal bite victims with local infiltration of Equine Rabies Immunoglobulin (ERIG) into and around animal bite wounds followed by anti-rabies vaccine (ARV).The main reason for non-use of ERIGs by medical profession is the fear of anaphylaxis and laborious process. The present study was taken up with the objectives to assess the clinical safety of a new ERIG, describe sociodemographic profile of ERIG recipients and compliance to Intra Dermal Rabies Vaccine (IDRV), who reported to Anti Rabies Clinic (ARC) of Mandya Institute of Medical Sciences (MIMS), Mandya.Methods: Descriptive study at ARC, MIMS, Mandya for a period of one year. The data was collected using structured questionnaire. The data was entered into Microsoft excel and results were expressed using descriptive statistics.Results: The study revealed that cat III animal bite victims were 3400 (56.3%), of these only 545 (16.0%) opted for the new ERIG. Skin Sensitivity Test (SST) showed positive results in 17 (3.1%) cases. Among the ERIG recipients 28 (5.1%) had mild adverse reaction to ERIG. The compliance rate was 49.2% for all 4 doses of IDRV.Conclusions: 3.1% showed positive result to SST. 5.1% had mild adverse reaction to ERIG.

Health-seeking behavior and compliance to post exposure prophylaxis among animal bite victims in India

In rabies endemic countries, where every animal bite is potentially a suspected rabid exposure, the exposed individuals should seek early and proper health care. It is also essential to complete the full course of postexposure vaccination to protect against rabies. The study aimed at determining the health-seeking behavior of animal bite victims; assessing the perceived risk of rabies transmission from different animals and knowledge on its prevention and finding out the compliance to complete course of rabies vaccination and associated factors. A multi-centric, health facility-based survey was conducted during May 2017 to January 2018 in six regional-representative states involving 18 health facilities. Study participants were animal bite victims attending the health facilities. The data from all the study participants across the country were compiled and analyzed using descriptive statistics and Chi-square test to find out the association of factors influencing compliance. Among a total of 529 animal bite victims, 83.6% sought postexposure prophylaxis coming directly to health facility; others visited nonallopathic/traditional healers/veterinarians/Auxiliary Nursing Midwifery before coming to health facility. The perceived risk of disease transmission and knowledge on the prevention of rabies was insufficient among the exposed victims. All participants were started with anti-rabies vaccination; the compliance rate for the full course of intramuscular rabies vaccination was 65.9% and for intra-dermal rabies vaccination, it was 85.1%. Among Category III exposures, only 46.2% received rabies immunoglobulin. Health-seeking behavior and compliance to complete course of anti-rabies vaccination is unsatisfactory, which has to be improved to prevent rabies.

Comparison of Immune Responses following Intradermal and Intramuscular Rabies Vaccination Methods

Comparison of Immune Responses following Intradermal and Intramuscular Rabies Vaccination Methods

Intradermal pre-exposure rabies vaccination in a Canadian travel clinic: 6-year retrospective observational study.

The intradermal route of vaccine administration for pre-exposure rabies prophylaxis, endorsed by the Canadian National Advisory Committee on Immunization, was implemented at a large travel clinic in Montréal in 2008. We evaluated the effect of intradermal vaccination availability on uptake of pre-exposure rabies prophylaxis and rates of seroconversion with intradermal vaccination. We conducted a retrospective cross-sectional study using data from December 2008 to December 2014. The number of travellers who received pre-exposure rabies prophylaxis before and after the introduction of intradermal vaccination was compared. Postvaccination antibody titres were measured in intradermal vaccination recipients. We compared demographic and travel characteristics between vaccinated and unvaccinated travellers and between travellers in the intradermal and intramuscular groups using univariate and multivariate analyses. The proportion of travellers who received pre-exposure prophylaxis increased after the introduction of intradermal vaccination (annual average of 300 travellers from December 2009 to December 2014 v. 183 travellers from December 2006 to December 2007). Seroconversion occurred in 99.9% of those in the intradermal group. Travellers who received pre-exposure prophylaxis were older (mean age 35.8 yr v. 32.1 yr) and had longer travel duration than those who did not receive pre-exposure prophylaxis. Travellers to Asia were more likely to receive pre-exposure prophylaxis, and travellers visiting friends and relatives were less likely to receive it. Travellers in the intradermal group were younger than those in the intramuscular group and were more likely to be travelling for tourism. The introduction of intradermal vaccination for pre-exposure rabies prophylaxis was associated with an increase in vaccination uptake. Reduced cost may be responsible for the increased coverage among younger travellers and those travelling for tourism. The high seroconversion rate after intradermal vaccination supports the effectiveness of this route of administration for pre-exposure rabies prophylaxis in immunocompetent people.

Safety of intradermal rabies vaccine as pre-exposure prophylaxis among veterinary students

Background: Animal bites are a major public health problem in our country. Pre-exposure vaccination using cell culture vaccines is a safe and effective method of preventing rabies and is recommended for anyone who will be at continual, frequent or increased risk of exposure to the rabies virus, as a result of their occupation, such as veterinarians, animal handlers and laboratory workers dealing with any lyssaviruses. The present study was done to assess the safety of purified chick embryo cell rabies vaccine administered as pre-exposure regimen.Methods:The present study assessed the safety of purified chick embryo cell rabies vaccine administered as a 3 dose intradermal pre-exposure vaccination in healthy volunteered veterinary students of Government Veterinary College, Bangalore. Results: 122 apparently healthy adults of both sex, between 18 and 30 years of age were enrolled in the study and 105 (86%) completed all three doses. A total of 342 doses of intradermal vaccine were administered, among which 38 adverse reactions were reported from 19 veterinary students. The adverse reactions were pain at the injection site 7 (2.1%), redness 13 (3.8%), itching at the site of injection 11 (3.2%), induration 6 (1.8%) and headache 1 (0.3%). All reactions subsided without any complication and none of them dropped out from the study because of any adverse drug reactions. Conclusions:Pre-exposure vaccination is a useful tool for protecting high risk groups and purified chick embryo cell rabies vaccine has proved to be safe and well tolerated by intradermal route.

Safety of Intradermal Rabies Vaccination as Pre Exposure Prophylaxis

Need for the study: WHO recommends pre exposure prophylaxis in rabies endemic countries for all individuals who are at increased risk of exposure to rabies such as veterinarians, rag-pickers, animal handlers, rabies researchers/laboratory workers, International travellers and children. Objectives: To assess the safety of rabies vaccine administered intradermally as pre-exposure prophylaxis among 3 high risk groups viz., children, rag-pickers and veterinarians. Methods: All the subjects who volunteered from each of the 3 risk groups were taken for the study and were given purified chick embryo cell rabies vaccine having a potency of >2.5 IU per dose, intradermally as pre exposure prophylaxis on days 0, 7 and 21. Subsequently, all were followed up to assess the safety of intradermal rabies vaccination by recording the adverse drug reactions from the day of administration of first dose of vaccination upto 2 weeks after the last dose of vaccination. Results: The present study included 150 children, 225 rag-pickers and 122 veterinary students. The adverse drug reactions to rabies vaccination among these groups were 5.1%, 5.0% and 10.4% respectively which were mild in nature and subsided spontaneously or by taking symptomatic treatment and none of the subjects dropped out because of adverse drug reactions. Conclusion: Pre exposure prophylaxis against rabies by intradermal route is safe and well tolerated by high risk groups, which may be considered as a strategy for eliminating the disease by 2030.

Safety and immunogenicity of intradermal rabies vaccination for post exposure prophylaxis

Background: The affordability to anti-rabies vaccine (ARV) for intramuscular administration in post exposure prophylaxis (PEP) is a major constraint. Therefore, in countries, where there are financial constraints, WHO recommends intradermal rabies vaccination (IDRV) that reduces the quantity and cost of vaccination. The aim of the study was to evaluate the safety and immunogenicity of IDRV implemented under National pilot project. Methods: A longitudinal study was conducted at anti rabies clinic (Government referral hospital), India where IDRV is implemented. The study included 515 animal bite cases who received PEP as recommended by WHO. ARV was administered intradermally using updated Thai red-cross regimen. Results: The incidence of adverse drug events was 9.7% and all resolved without any complication. The geometric mean concentration of rabies virus neutralizing antibodies among the vaccinees was 11.89IU/mL on day 14, which was above the WHO recommended titers of ≥ 0.5IU/mL. Conclusions: IDRV was found to be safe and immunogenic in PEP.