Rabies Antibody Research Articles

A time-resolved fluoroimmunoassay for assessing rabies antibody titers in the sera of vaccinated human subjects

Several studies have investigated the use of simple in vitro tests for the assessment of rabies antibody titers in serum samples from vaccinated human subjects, which would allow the effectiveness of rabies vaccination to be conveniently evaluated. To this end, a novel time-resolved fluoroimmunoassay (TRFIA) for the assessment of rabies antibody titers was established in this study for evaluating the effectiveness of protection against rabies. The TRFIA had a satisfactory limit of detection value (0.035 IU/mL) under optimal conditions. Additionally, the application of the TRFIA was demonstrated in 68 serum samples with satisfactory results. The coefficient variations (CVs) were all <10%, and the recoveries were in the range of 90–110%. The correlation coefficient of titer values obtained using the present TRFIA and the rapid fluorescent focus inhibition test (RFFIT) was 0.733, with a coincidence rate regarding the evaluation results (protected or not protected by vaccination) of 100%. The preliminary results confirmed that the TRFIA had a higher performance than an enzyme-linked immunosorbent assay (ELISA), and could potentially replace the ELISA. Based on these results, the novel TRFIA appears to be a convenient tool for the evaluation of rabies vaccination results based on serum samples from vaccinated human subjects.

The Influence of β-1,3-1,6-Glucans on Rabies Vaccination Titers in Cats.

β-glucans have been shown to stimulate the immune system in several animal species. The aim of this study was to evaluate the immune stimulation capacity of a fully formulated diet with β-1,3-1,6-glucans in cats, by assessing the rabies antibody titer after vaccination. Thirty-five healthy cats were recruited. The cats were placed into two groups and fed a standard diet in accordance with body weight. One group had the β-glucans incorporated into the diet; the other group served as the control group. After two weeks of dietary adjustment; the rabies vaccine (Imrab® 3 TF; Merial) was administered on days 0 and 21. Blood samples were taken on days 0, 21, and 42. Titers were determined with the rapid fluorescent foci inhibition test (RFFIT). Titers at days 21 and 42 were compared between the two groups in a linear mixed effects model. This study showed that the animals receiving the non-supplemented feed had higher post-vaccination rabies antibody titers. This indicates that, in contrast to other animal species, the β-glucan supplemented diet did not have the expected positive effect on the rabies antibody titers in cats.

The Presence of Rabies Virus-Neutralizing Antibody in Wild Boars (Sus scrofa), a Non-Target Bait Vaccine Animal in Korea.

Oral vaccination with bait is an effective method to prevent rabies in wildlife, but non-target wild animals may also ingest the bait vaccine. In Korea, the target animal of the rabies bait vaccine is the raccoon dog (Nyctereutes procyonoides). Bait vaccines have been distributed in Korea for 20 years; although wild raccoon dogs have been tested for antibodies, rabies antibodies have never been investigated in non-target wild animals. Therefore, this study investigated rabies antibody formation in wild boars (Sus scrofa), which is likely the main competitor for the bait vaccine in Korea. In bait areas, 20 of 109 wild boars (18.3%) were seropositive, and 39 of 470 wild boars (8.3%) in non-bait areas were also seropositive. These results provide insights regarding bait uptake or vaccination in non-target wild boars.

Studies on humoral immunity in dogs after use of rabies inactivated vaccines formulated with Montanide ISA 70 VG and GEL 01 adjuvants

Despite all the efforts made, the issue of rabies in the world does not lose its relevance. As an acute endemic infection, it poses a considerable danger to both animals and humans. The leading role in the transmission of rabies to humans belongs to diseased dogs; stray animals can be potential sources of rabies agent, which increases the risk of transmitting a deadly virus to humans. Rabies prevention in dogs around the world is carried out by counting the number of these animals, their mandatory routine immunization and evaluating the effectiveness of vaccination against the accumulation of rabies virus-neutralizing antibodies. Inactivated vaccines based on different viral strains formulated with a wide range of adjuvants are used to induce a protective level of humoral immunity against rabies in dogs (≥ 0.5 IU/cm3), which allows vaccines with high safety and effectiveness for the target animal species to be obtained. The article presents the results of the study of humoral immunity in 20 non-pedigree dogs 21 days after the administration of rabies inactivated vaccines based on culture rabies virus from ARRIAH strain formulated with various adjuvants. The presented rabies vaccines formulated with oil adjuvant Montanide ISA 70 VG and gel adjuvant Montanide GEL 01 were innocuous and safe and induced strong immunity in all vaccinated animals. The vaccine formulated with Montanide ISA 70 VG adjuvant in case of a single administration in the dose of 1.0 cm3 induces formation of rabies virus-neutralizing antibodies in the level of 2.4 times higher than the vaccine formulated with Montanide GEL 01 adjuvant. The highest levels of rabies antibodies in dogs were 48.1 ± 3.7 and 28.3 ± 1.5 IU/cm3 and were observed with the use of rabies inactivated emulsion vaccine in the doses of 3.0 and 1.0 cm3 respectively.

Possibility of Immediate Introduction of a Single-Dose Antibody Induction Test as a Refinement of the NIH Test for Inactivated Rabies Vaccine Potency Determination.

Antibody induction test (AIT) is a promising candidate as a refinement of the troublesome National institutes of Health (NIH) test in the sense of animal welfare 3R approach for determination of potency of inactivated rabies vaccines for veterinary and human use. In this study, we initially try to develop AIT as a suitable alternative to NIH test, to achieve a reduction of test duration and diminish animal suffering by omitting intracerebral CVS infection and measuring humoral immunity upon vaccination. Designs of both multi-dose and single-dose AIT were examined. Biological reference preparation, batch 5 with assigned titer of 10 IU/vial, was taken as both standard and test vaccine. Six consecutive AITs were performed and eight pools of sera in each AIT were tested in triplicate by rapid fluorescent focus inhibition test. We estimated the upper detection limit and calculated test variability for individual dilutions. For multi-dose AIT, we estimated the dose-response function and performed calculations of final test results and statistical validity parameters for both linear and sigmoidal model using CombiStats program. Sigmoidal 4-parameter dose-response model was found optimal. Presented design of multi-dose AIT showed a satisfactory detection limit for testing of inactivated rabies vaccines for both veterinary and human use. However, due to nonconformity of obtained results with statistical validity criteria, we concluded that the presented model of multi-dose AIT was unsuitable for introduction in routine practice. However, we concluded that there was a realistic option for introduction of two versions of single-dose AIT. The first version would be with two standard vaccine controls and could be introduced immediately, while the second version would include testing of the sample only and rely on comparison of the induced rabies antibody level with absolute cut-off limits set in advance.

Evaluation Of Anti-Rabies Hyperimmune Serum Prepared Using Different Adjuvants

ABSTRACT Hyper immune antirabies serum have been prepared in horses using inactivated and live attenuated rabies ERA vaccines with three different adjuvants including 20% Rehydra gel ; 5% Pet gel-A and 20% calcium phosphate gel. Such preparation was conducted through inoculation of each of three horse groups with 8 increased doses (one dose twice weekly) of an inactivated vaccine followed by 4 doses of a live attenuated vaccine (one dose twice weekly) with the same adjuvant. All prepared vaccine formulae were found to be free from foreign contaminants and safe with no post inoculation abnormal signs in inoculated mice. Monitoring of the levels of exhibited rabies antibodies in the sera of immunized horses using serum neutralization test (SNT) and Rabies virus antibody quantitative ELISA kit revealed that the prepared rabies vaccines with 5% Pet gel A adjuvant induced the highest antibody titers (2048 by SNT and 2.20 by ELISA kit) with expected protection percentage 96.14% followed by those induced by 20% Calcium phosphate gel recording the values of 2048 by SNT and 2.11 by ELISA kit with expected protection percentage 92.2%. Lower values (1024 by SNT; 2.05 by ELISA kit and 89.59% protection percentage) were recorded for the Rehydra gel adjuvanted vaccine. These obtained data reflect the safety and potency of the prepared horse anti-rabies hyper immune serum (HARHIS) to be used for post exposure treatment in emergency cases and that is the Pet gel A was the best adjuvant to be used.

IMMUNOGENESIS IN THE DESTRUCTION OF CELLS OF THE NERVOUS SYSTEM UNDER THE INFLUENCE OF THE RABIES VIRUS

The nature of rabies immunity is not well understood, the zones of deployment of protective mechanisms are unknown, and the place where antibodies meet with the virus is unclear. The issue of the mechanism of protection of the central nervous system against rabies virus is relevant. It has been hypothesized that protection (immunity) of the central nervous system to the rabies virus is induced by the distant interaction of antibodies on the nerve сells and is mediated by the energy-information field of specific antibodies circulating in the blood vessels of the central nervous system. To confirm this hypothesis, the non-contact effect of rabies antibodies on the rabies virus (strain “Shchelkovo-51”) in the culture cell (BHK-21/13) and the decrease in antigen accumulation from 1.7 to 2.9 times were experimentally shown. The obtained data confirm the main point of the hypothesis on the protection of the central nervous system against the rabies virus using an energy-information biofield.

Kertas Saring sebagai Media Transpor Darah untuk Pemeriksaan Antibodi Rabies

Rabies is a zoonotic disease. Rabies protection level detection was performed using antibody titration. Blood sampling activities in the field require special handling to avoid blood lysis, the sample delivery requires a cold chain with a stable temperature. Alternative method forwhole blood sample delivery using filter paper were carried out on 48 samples from susceptible animals (dogs and cats) transpored through the Soekarno Hatta Agricultural Quarantine Center. This study was designed to investigate the feasibility of filter paper sampling of blood at temperature of 26 °C to detect of rabies antibodies using indirect method of ELISA. The results of statistical analysis of Randomized Block Design and Tukey's test showed that the antibody titres of whole blood extracted from filter paper diluted in the PBS T 100 μl were equivalent to antibody titres of serum. Assesment of filter paper capability has sensitivity and specificity as much as 96% and 76%, positive predictive value of 67%, negative predictive value of 94% and reliability level of filter paper were 0.5 is moderate category. This indicates that the filter paper can be used as an alternative method of blood transport medium for rabies ELISA test.

Volatile metabolomic signatures of rabies immunization in two mesocarnivore species.

Rabies is a zoonotic disease caused by infection with rabies virus, which circulates naturally in several wild carnivore and bat reservoirs in the United States (US). The most important reservoir in the US from an animal and public health perspective is the raccoon (Procyon lotor). To prevent the westward expansion of a significant raccoon rabies epizootic along the eastern seaboard, an operational control program implementing oral rabies vaccination (ORV) has existed in the US since the 1990s. Recently, two vaccine efficacy studies conducted with raccoons and striped skunks (Mephitis mephitis) provided the opportunity to determine if volatile fecal metabolites might be used to non-invasively monitor ORV programs and/or predict virus protection for these species. The volatile metabolome is a rich source of information that may significantly contribute to our understanding of disease and infection. Fecal samples were collected at multiple time points from raccoons and striped skunks subjected to oral treatment with rabies vaccine (or sham). Intramuscular challenge with a lethal dose of rabies virus was used to determine protection status at six (raccoons) and 11 (skunks) months post-vaccination. In addition to fecal samples, blood was collected at various time points to permit quantitative assessment of rabies antibody responses arising from immunization. Feces were analyzed by headspace gas chromatography with mass spectrometric detection and the chromatographic responses were grouped according to cluster analysis. Cluster scores were subjected to multivariate analyses of variance (MANOVA) to determine if fecal volatiles may hold a signal of immunization status. Multiple regression was then used to build models of the measured immune responses based on the metabolomic data. MANOVA results identified one cluster associated with protective status of skunks and one cluster associated with protective status of raccoons. Regression models demonstrated considerably greater success in predicting rabies antibody responses in both species. This is the first study to link volatile compounds with measures of adaptive immunity and provides further evidence that the volatile metabolome holds great promise for contributing to our understanding of disease and infections. The volatile metabolome may be an important resource for monitoring rabies immunization in raccoons and striped skunks.

Detection of rabies antibodies in wild boars in north-east Romania by a rabies ELISA test

BackgroundIn the last few decades, Romania has been considered one of the European countries most affected by animal rabies, but a combination of oral rabies vaccination (ORV) campaigns in foxes alongside mandatory vaccination of pets has substantially decreased the number of rabies cases in recent years.The objective of this study was to detect rabies antibodies in wild boar serum and thoracic fluid samples collected during the hunting season after ORV campaigns in north-eastern Romania in order to identify if wild boars are substantial competitors to foxes for ORV baits.ResultsWhen the 312 wild boar samples were tested by ELISA (BioPro ELISA, Czech Republic), 42.31% (132/312) demonstrated rabies antibodies. In order to compare these wild boar results in terms of the percentage of immunisation, fox samples were also included in the study, and in this case only 28.40% (98/345) demonstrated rabies antibodies by ELISA. To check the diagnostic sensitivity and specificity of this ELISA, those samples with a sufficient volume from both species that had tested either negative or positive with an initial ELISA were then tested with the Fluorescent Antibody Virus Neutralisation (FAVN) assay. The overall concordance between the BioPro ELISA and FAVN test was 74.26% (75/101) in wild boar samples and 65.66% (65/99) in fox samples, 140 out of 200 samples being correlated with the two methods, although no significant statistical difference (p = 0.218) between the two species was registered. We found a good agreement by both tests for the ELISA-positive samples (91.30%), however the situation was different for the ELISA-negative samples, where a low agreement was demonstrated (41.18%).ConclusionsThis study reports for the first time the presence of rabies antibodies in wild boar samples collected during the hunting season in Romania after ORV campaigns in rabies endemic areas. It is also the first study to demonstrate that ELISA BioPro can be used on wild boar samples with satisfactory results compared to the FAVN test for this species.

Sero Prevalence of Virus-neutralizing Antibodies for Rabies in Street Dogs of Kathmandu Valley, Nepal

Introduction: Rabies is a vaccine-preventable viral zoonotic disease that remains a serious global public health concern. Rabies vaccination with adequate coverage of the canine population has been shown to control rabies outbreaks among canines and to prevent the transmission of rabies from dogs to humans. As vaccination is the primary control measure for rabies, it is important to determine the level of anti-rabies antibodies in animals in order to determine the effectiveness of the control measures being implemented. Materials &amp; Methods: Blood samples were collected from 50 street dogs (August 2016 to December 2016) in Kathmandu, Bhaktapur and Lalitpur districts. Rabies sero-conversion on the separated serum was quantified using PlateliaTM Rabies II Kit (Bio-Rad, China) according to the manufacturer’s recommendations. Results: Eighty percent (40/50) of the serum samples surpassed the requested level of rabies antibodies, suggesting good coverage of vaccination among street dogs. Conclusion: However, an active dog surveillance system with a dog registration process before and after vaccination campaigns, and a multi-dimensional approach including all stakeholders, are necessary to eradicate rabies from the canine population in Nepal.

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.

Activity of antirabic antibodies in blood serum under the different storage conditions

Objective: to determine of the activity of antirabic antibodies in blood serum under the different conditions of storage. Materials and methods. Samples of serums from dogs and cats, which got into the laboratory of rabies diagnostics of SSRILDVSE for research. Rabies virus-neutralizing activity of blood serum was tested using the FAVN test. Serum samples were sorted by species, age of animals and titer of rabies antibodies. Aliquots were stored at a temperature of +4 ± 0.5 °C and –20 ± 0.2 °C and exposed to 5 fold defrosting-freezing. The tests were carried out at the beginning, after 7, 14, 21, 28, 56, 84 days. Results. Period of storage of blood serum at a temperature +4 ± 0.5 °C was 28 days for one of test samples, three of samples were stored for 21 days, but the maximum period for all samples was 14 days. The initial titers of rabies antibodies in sera ranged from 1.95 to 17.74 IU/cm3 and were relatively stable during the period of experiment. In frozen samples of serum the stability of the titer of rabies antibodies was observed throughout the period of experiment. As a result of freezing and thawing of serum, a decrease in the activity of anti-rabies antibodies was observed. Two to three times decrease compared with the initial values was already observed on the 3rd cycle. The initial indicators were at the level of 0.50–0.66–0.87 IU/cm3. On the 2nd and 3rd cycles, the antibody level was 0.38–0.29–0.17 IU/cm3, respectively, which is below the minimum protective titer — 0.50 IU/cm3. Conclusion: The results presented in our study, showed that for serum freezing the temperature of –20 °C is the optimal condition for storage. Freezing samples showed stability in maintaining the level of titers of rabies antibodies. After thawing of experimental samples of serum, they should be stored at a temperature of +4 °C, but not longer than for 14 days. The results obtained indicate that the temperature and duration of storage of serum is an important factor in obtaining reliable results. It should be taken into account by veterinary medicine specialists when transfer samples for research in laboratory

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In Rwanda, rabies is a threat to public health and the control is mainly done by vaccinating pet dogs annually. However, it is unknown whether dogs that received rabies vaccination achieved protective antibody levels. This study assessed factors influencing rabies antibody titres in vaccinated and non-vaccinated pet dogs in Kigali City, Rwanda. A questionnaire was used to gather information on 137 study dogs and clotted blood samples were collected from 93 healthy pet dogs. Enzyme-Linked Immunosorbent Assay (ELISA) was used to quantify rabies antibody titres. Frequency and geometric mean titres, as well as chi-square and regression analysis, were used to study the data. The results showed that 35% of the vaccinated dogs had antibody titres below 0.5 EU/ml while 53.8% of the non-vaccinated dogs had detectable antibodies varying between 0.133 and 0.238 EU/ml. All types of rabies vaccine (A, B, C, D, and E) used elicited diverse antibody levels and the overall mean titre was 1.071. Vaccinated dogs had a higher mean number of rabies antibodies (11.776059735) than non-vaccinated dogs (1.41579378). Mean titres decreased with time between vaccination and sampling, that is, 1.559, 0.949, and 0.934 in dogs sampled 1-5, 6-9 and 10-12 months following vaccination, respectively. The mean titres increased steadily from the first to the fourth vaccination times, namely 0.608, 1.320, 1,395, and 1.787, respectively. Mean titres increased with dogs&rsquo; age and varied between 0.638 and 1.515. Factors including vaccination status, number of vaccination, time elapsed between vaccination and sampling, and age at vaccination influenced rabies antibody titres. Irrespective of the type of rabies vaccine applied, 99% of vaccinated dogs produced rabies antibodies though not all had protective levels. Considering the high number of vaccinated dogs that were poor responders to rabies vaccination, further studies should be undertaken to investigate and understand the phenomenon. Key words: Rabies, vaccination, domestic dogs, seroconversion, Kigali city, Rwanda. &nbsp

Flow cytometry for the analysis of virusneytralizing activity of antirabies serum and immunoglobulin drug

Here, we discuss development of f low cytometry technique for determining level of rabies antibodies in immune sera and immunoglobulin preparations, which is based on measuring fluorescence level in Vero cell line added with a mix of serially diluted anti-rabies serum or immunoglobulin preparation together with Moscow 3253 attenuated rabies virus strain, adapted for reproduction in cell lines. For this, rabies sera and immunoglobulin preparation were diluted 1:20 and 1:200 with PBS, respectively, whereas rabies virus was recommended for use at dose of 0.1 ID50/cell. Cell membrane fixation and permeabilization were performed by using a Cytoperm/Cytofix reagent (BD Pharmingen, USA) containing formaldehyde able to inactivate rabies virus, thus complying with biological safety regulations. Anti-rabies FITC-conjugated immunoglobulin (FGBI ARRIAH, Russia) was recommended for staining, that does not limit using similar reagents. Then, a f low cytometer equipped with a 20 mW argon laser (488 nm emission wavelength, throughput 500 cells per second) was used for analysis. Vero cells displaying a fluorescence intensity exceeding 10 arbitrary units were considered infected. Flow cytometry allows to precisely measure amount of experimental infected cells as well as degree of infection by evaluating cell f luorescence intensity. Amount of antibodies in the samples examined by us was calculated by building a calibration curve based on depicting data for a standard rabies immunoglobulin with activity of 30 IU/ml (NIBSC, Potters Bar, United Kingdom). A high correlation between the data obtained by us and results from other detection methods used to assess activity of anti-rabies preparations such as biological neutralization of rabies virus in white mice (0.92) and modified FAVN test (0.98) was demonstrated. The comparison of the results of the analysis of the level of rabies antibodies obtained using f low cytometry, and the results obtained in tests in vivo, was carried out for the first time. Moreover, it is worth noting that for the first time the level of anti-rabies antibodies assessed by f low cytometry and in vivo tests was compared. An opportunity to perform rapid and easy-to-do analysis on assessing amount of infected cells by measuring fluorescence intensity in f low cytometry assay would allow to apply this approach for quality control while developing and manufacturing immunobiological anti-rabies preparations.

Rabies virus monitoring in bat populations in Rondônia state, Brazil.

The Jirau hydroelectric power plant built in Rondônia state has environmental impacts that could be relevant to rabies outbreaks. Bat populations were monitored for rabies by fluorescent antibody testing and simplified fluorescent inhibition microtesting between 2010 and 2015. All 1,183 bats tested negative for rabies. The prevalence of rabies antibodies was 17.5% in 1,049 bats. The rabies antibody dosage was not reactive in samples collected before the environmental changes, and there was a progressive increase in subsequent collections that could indicate an increase in rabies virus circulation among bats and risk of a rabies outbreak.

Evaluation of Antibody Responses of Dogs Vaccinated with Three Imported Inactivated Anti-Rabies Vaccines in Nigeria

Dog anti-rabies vaccines are imported into Nigeria to complement the quantity being produced by the National Veterinary Research Institute, Vom, Plateau State, Nigeria. Routinely these imported vaccines are expected to be tested for safety, potency and efficacy; however this is hardly done. This study was carried out to determine the immunogenicity of three imported anti rabies vaccines available in Nigeria. Twenty indigenous breeds of dogs aged between 3 and 4 months were randomly assigned to 4 groups (A,B,C and D), groups A,B and C were subsequently vaccinated with a single dose of three different brands of commercially available inactivated anti- rabies vaccines while D was the control. Rabies antibodies were measured fortnightly until it started waning in all dogs, using indirect Enzyme linked immunosorobent assay. Responses of dogs’ immune system to the three anti-rabies vaccines varied greatly. Groups B mean antibody titres peaked on day 14 post vaccination while groups A and C mean antibody titres peaked on day 28 (A=5.74±0.643 EU/Ml, B=0.184±0.091 EU/Ml and C=0.237±0.080 EU/Ml). All dogs in group A, two in group C and none in group B had protective antibody titres in the course of this study. The mean antibody titres against rabies on days 14, 28 and 56 were significantly higher in group A than in groups B and C. There is need for the stakeholders in Nigeria to know that all imported anti-rabies vaccines may not be immune-protective. There is there need for regular evaluation of batches of commercially available anti-rabies vaccines in the country for efficacy at port of entry before release; in order to win the battle against human rabies by 2030.

Rabies immune status of raccoon dogs residing in areas where rabies bait vaccine has been distributed.

Since 2000, large amounts of rabies bait vaccine have been distributed in two provinces where raccoon dog-mediated rabies has occurred. A total of 146 raccoon dogs were caught in Gangwon and Gyeonggi Provinces from January 2017 to June 2018, and raccoon dog blood samples were collected. Of the 146 raccoon dogs, 13.7% (20/146) had rabies antibodies. In Gyeonggi and Gangwon provinces, the rate of rabies antibody was 8.5% (5/59) and 17.2% (15/87), respectively. Considering these results, it would be desirable to improve the distribution method or use a new bait vaccine to prevent animal rabies in South Korea.

Serological profiling of rabies antibodies by enzyme-linked immunosorbent assay and its comparative analysis with rapid fluorescent focus inhibition test in mouse model

Aim:In this study, we have used enzyme-linked immunosorbent assay (ELISA) as an alternative test to replace the cumbersome rapid fluorescent focus inhibition test (RFFIT) to ascertain the immune status of immunized mice against rabies virus.Materials and Methods:Rabies is a devastating disease worldwide caused by rabies virus. Proper usage of pre- or post-exposure rabies vaccine can prevent the disease transmission. In this study, mice were immunized with Vero cell-adapted inactivated rabies vaccine. RFFIT was used as a test to determine the serum neutralizing titers in infected/vaccinated mice. Seroprofiling of mice sera was done in vitro by ELISA.Results:Twenty-one days post-immunization, both ELISA and RFFIT assays indicated similar antibody levels in mice sera that were immunized with Vero cell-adapted inactivated rabies vaccine. Both the tests were correlated, and the linearity was verified by the regression line (R²=0.979).Conclusion:In this study, we profiled the serological status of Vero cell-adapted inactivated rabies vaccine through ELISA in mice model that correlated well with the OIE gold standard test RFFIT.

Indian Academy of Pediatrics (IAP) Advisory Committee on Vaccines and Immunization Practices (ACVIP) Recommended Immunization Schedule (2018-19) and Update on Immunization for Children Aged 0 Through 18 Years

There is a need to revise/review recommendations regarding existing vaccines in view of current developments in vaccinology. Advisory Committee on Vaccines and Immunization Practices (ACVIP) of Indian Academy of Pediatrics (IAP) reviewed the new evidence, had two meetings, and representatives of few vaccine manufacturers also presented their data. The recommendations were finalized unanimously. To revise and review the IAP recommendations for 2018-19 and issue recommendations on existing and certain new vaccines. The major changes in the IAP 2018-19 Immunization Timetable include administration of hepatitis B vaccine within 24 hours of age, acceptance of four doses of hepatitis B vaccine if a combination pentavalent or hexavalent vaccine is used, administration of DTwP or DTaP in the primary series, and complete replacement of oral polio vaccine (OPV) by injectable polio vaccine (IPV) as early as possible. In case IPV is not available or feasible, the child should be offered three doses of bivalent OPV. In such cases, the child should be advised to receive two fractional doses of IPV at a Government facility at 6 and 14 weeks or at least one dose of intramuscular IPV, either standalone or as a combination, at 14 weeks. The first dose of monovalent Rotavirus vaccine (RV1) can be administered at 6 weeks and the second at 10 weeks of age in a two-dose schedule. Any of the available rotavirus vaccine may be administered. Inactivated influenza vaccine (either trivalent or quadrivalent) is recommended annually to all children between 6 months to 5 years of age. Measles-containing vaccine (MMR/MR) should be administered after 9 months of age. Additional dose of MR vaccine may be administered during MR campaign for children 9 months to 15 years, irrespective of previous vaccination status. Single dose of Typhoid conjugate vaccine (TCV) is recommended from the age of 6 months and beyond, and can be administered with MMR vaccine if administered at 9 months. Four-dose schedule of anti-rabies vaccine for Post Exposure Prophylaxis as recommended by World Health Organization in 2018, is endorsed, and monoclonal rabies antibody can be administered as an alternative to Rabies immunoglobulin for post-exposure prophylaxis.