Oral Rabies Vaccination Research Articles

A novel inactivated oral rabies vaccine with the incorporation of U-OMP19 enhances the immunogenicity by reducing viral proteins degradation and activating dendritic cells in a mouse model

Currently, dogs, especially stray dogs, and/or wild animals are the main sources of rabies transmission, and oral vaccination is the most practical way to control rabies in these animals. Safety and efficacy are two key criteria for developing oral vaccines. Concerning the efficacy of oral vaccines, degradation of immunogens by gastrointestinal fluid is a major challenge, resulting in suboptimal immune responses after vaccination. For safety reasons, inactivated vaccines are the most optimal choice. In the present study, a recombinant rabies virus (RABV) with un-lipidated outer membrane protein 19 (U-OMP19) of Brucella spp incorporated into RABV virions, designated as LBNSE-OMP19-G, was constructed and rescued. We found that U-OMP19 was incorporated into LBNSE-OMP19-G virion, which could protect RABV G protein from digestion by gastrointestinal fluids in vitro. Moreover, the immunogenicity of LBNSE-OMP19-G as an inactivated oral vaccine was evaluated, and the inactivated LBNSE-OMP19-G could activate more dendritic cells (DCs) and promote the generation of follicular helper T (TFH) cells, germinal center (GC) B cells, and plasma cells in immunized mice compared with those in mice immunized with parent virus LNBSE, which consequently induced a higher level of virus neutralizing antibody and provided better protection after a lethal challenge of rabies. These data indicate that LBNSE-OMP19-G, which has good safety and immunogenicity, could be a potential inactivated oral rabies vaccine candidate.

Rabies situation in the Moscow Oblast in 2011–2023 and the role of oral vaccination of wild carnivores against rabies

Rabies is a zoonotic viral disease of all warm-blooded animals caused by a neurotropic virus, member of the Lyssavirus genus of the Rhabdoviridae family. About 59,000 people die from hydrophobia globally every year. According to the World Health Organization, the red fox (Vulpes vulpes) and the common raccoon dog (Nyctereutes procyonoides) are the main reservoirs and vectors among carnivores of the rabies virus in Europe. The paper describes animal rabies situation in 2011–2023 and the role of oral vaccination of wild carnivores against rabies in the Moscow Oblast. The region is a part of the Central Federal District and located in the center of the Russian plain bordering seven Oblasts (Tver, Smolensk, Kaluga, Tula, Ryazan, Vladimir and Yaroslavl Oblasts), which are also rabies infected. Notwithstanding the metropolis growth, the number of wild carnivores in the Moscow Oblast remains high. Comprehensive preventive measures to control the population of the wild carnivores are taken to stabilize the rabies situation and decrease the incidence, innovative achievements in laboratory diagnosis are introduced, population immunity of wild carnivores by oral vaccination is improved and the epidemic situation in neighboring regions is analyzed. In 2017 the systemic, consistent and thoroughly organized campaign was started – the oral vaccines were distributed by light aircrafts. The research revealed the correlation between the decrease in annual number of reported rabies cases and increase in the amounts of oral vaccines distributed. The use of controlling devices (camera traps) confirmed that oral rabies vaccines are consumed by the target animals (red foxes). The onward systemic, methodical approach to rabies prevention will mitigate the risks of rabies occurrence in the Moscow Oblast.

Spatial Clustering of Rabies by Animal Species in New Jersey, United States, from 1989 to 2023.

Identifying spatial clusters of rabies in animals aids policymakers in allocating resources for rabies prevention and control. This study aimed to investigate spatial patterns and hotspots of rabies in different animal species at the county level in New Jersey. Data on animal rabies cases from January 1989 to December 2023 were obtained from the New Jersey Department of Health and aggregated by county. Global Moran's index (I) statistics were computed for each species to detect global spatial clustering (GeoDa version 1.22). Local Moran's indicators of spatial association (LISA) were computed to identify local clusters of rabies. The results from the LISA analysis were mapped using ArcGIS Pro to pinpoint cluster locations. A total of 9637 rabies cases were analyzed among raccoons (n = 6308), skunks (n = 1225), bats (n = 1072), cats (n = 597), foxes (n = 225), and groundhogs (n = 210). A global Moran's test indicated significant global spatial clustering in raccoons (I = 0.32, p = 0.012), foxes (I = 0.29, p = 0.011), and groundhogs (I = 0.37, p = 0.005). The LISA results revealed significant spatial clustering of rabies in raccoons and foxes in southeastern New Jersey and in groundhogs in northern New Jersey. These findings could guide the development of targeted oral rabies vaccination programs in high-risk New Jersey counties, reducing rabies exposure among domestic animals and humans.

Oral rabies vaccination of foxes in Türkiye, 2019–2022

BackgroundRabies in Turkey is maintained by dogs, but following a sustained spill-over, red fox mediated rabies had spread from the Aegean region to the central part of Türkiye. During the past four years from 2019 to 2023 large scale efforts used oral rabies vaccination (ORV) to control rabies in red foxes. Here, we present the results of the largest ORV campaign on the Asian continent. MethodsORV campaigns were carried out twice a year in spring and autumn with a targeted bait density of 20–23 baits/km2. Monitoring of ORV campaigns included the GIS-based analyses of bait distribution, the assessment of bait uptake through biomarker detection and the determination of seroconversion (sero-positivity in ELISA) in the target species collected within the vaccination area. For determination of fox rabies incidence in vaccination areas as the main indicator of the performance of the ORV campaigns, epidemiological data was obtained from the national passive surveillance program. ResultsAerial bait distribution was highly accurate, with >99 % of baits being recorded from targeted zones, thus meeting the desired bait densities. Although the overall bait uptake (28.1 %; 95 %CI: 23.2–32.8) and seroprevalance (36.3 %; 95 %CI: 30.0–43.2) were low, rabies incidence drastically decreased in ORV areas and rabies was eliminated from western and central parts of Turkey, with no reported cases in foxes from ORV areas in 2022 and 2023. ConclusionsA large-scale ORV campaign against fox rabies using high quality vaccine baits and the GIS-aided and monitored bait distribution was able to control fox mediated rabies in the western and central parts of Türkiye. Rabies control both in dogs and foxes should be expanded to cover also the eastern parts of Türkiye, to become eventually rabies free.

Genetic Tracking of a Rabid Coyote (Canis latrans) Detected beyond a Rabies Enzootic Area in West Virginia, USA.

Wildlife translocation and cross-species transmission can impede control and elimination of emerging zoonotic diseases. Tracking the geographic origin of both host and virus (i.e., translocation versus local infection) may help determine the most effective response when high-risk cases of emerging pathogens are identified in wildlife. In May 2022, a coyote (Canis latrans) infected with the raccoon (Procyon lotor) rabies virus variant (RRV) was collected in Lewis County, West Virginia, USA, an area free from RRV. We applied host population genomics and RRV phylogenetic analyses to determine the most likely geographic origin of the rabid coyote. Coyote genomic analyses included animals from multiple eastern states bordering West Virginia, with the probable origin of the rabid coyote being the county of collection. The RRV phylogenetic analyses included cases detected from West Virginia and neighboring states, with most similar RRV sequences collected in a county 80 km to the northeast, within the oral rabies vaccination zone. The combined results suggest that the coyote was infected in an RRV management area and carried the RRV to Lewis County, a pattern consistent with coyote local movement ecology. Distant cross-species transmission and subsequent host movement presents a low risk for onward transmission in raccoon populations. This information helped with emergency response decision-making, thereby saving time and resources.

Evaluation of safety and immunogenicity of a genetically modified rabies virus for use as an oral vaccine in several non-target species1

Oral immunization is an alternative or supplementary approach that can significantly improve dog vaccination coverage, especially for free-roaming dogs. Safe and effective oral rabies vaccines for dogs are still being sought. In our previous studies, we generated a genetically modified rabies virus (RABV) ERA strain, rERAG333E, containing a mutation from arginine (Arg, R) to glutamic acid (Glu, E) at residue 333 of the G protein (G333E). Our previous results demonstrated that rERAG333E was safe for adult mice and dogs, and oral vaccination with rERAG333E induced a strong and long-lasting protective immune response in dogs. Here, we further investigated the safety and immunogenicity of rERAG333E in non-target species, including suckling mice, rhesus monkeys, foxes, raccoon dogs, piglets, goats, and sheep. Suckling mice studies demonstrated that the G333E mutation significantly reduced the virulence of the ERA strain. All of the suckling mice aged 10 days and above survived and showed no apparent signs of disease after intracerebral inoculation with rERAG333E. Animal studies demonstrated that rERAG333E was safe in rhesus monkeys, foxes, raccoon dogs, piglets, goats, and sheep. None of those animals inoculated orally with 10 times the intended field dose of rERAG333E showed abnormal clinical signs before and after the booster immunization with Rabvac 3, an inactivated rabies vaccine. Meanwhile, oral inoculation with rERAG333E induced strong neutralizing antibody (NA) responses to RABV in rhesus monkeys, foxes, raccoon dogs, and piglets. These results demonstrated that rERAG333E has the potential to serve as a safe oral rabies vaccine for dogs.

Rabies virus-based oral and inactivated vaccines protect minks against SARS-CoV-2 infection and transmission1

Minks are highly susceptible to SARS-CoV-2, and have transmitted SARS-CoV-2 to humans. Oral immunization is one of the most promising strategies to prevent SARS-CoV-2 infection and transmission in minks. Here, we generated three recombinant rabies viruses (RABV), rERAG333E/S6P, rERAG333E/DS6P and rERAG333E/BA2S6P, expressing the prefusion-stabilized SARS-CoV-2 spike protein of wild-type (S6P), δ (DS6P) or BA.2 (BA2S6P) strain based on an oral rabies vaccine candidate (rERAG333E). Oral or inactivated immunization of the three RABVs monovalent or trivalent were safe, and induced robust RABV neutralizing antibody and cross-antibody responses against the three SARS-CoV-2 in mice and minks. The challenge tests showed that two doses of rERAG333E-S6P as an oral or inactivated vaccine completely protected mice against mouse-adapted SARS-CoV-2 infection in the upper and lower respiratory tracts, and largely prevented viral replication and lung damage caused by wild-type SARS-CoV-2 infection in minks. Notably, we also confirmed that two doses of rERAG333E-S6P as an oral or inactivated vaccine can largely protect minks against wild-type SARS-CoV-2 transmission via respiratory droplets. Our findings suggest that rERAG333E-based COVID-19 vaccines appear to be suitable oral candidates to protect minks from SARS-CoV-2 infection and transmission, and may serve as inactivated vaccines for further investigation in humans.

Evaluation of Bait Acceptance and Immune Response in Local Dogs during an Oral Rabies Vaccination Field Study in Morocco.

The objective of this study was to evaluate the bait preference of three selected bait types by local dogs and the induced immunogenicity of the oral rabies vaccine strain SPBN GASGAS in Morocco. The vaccine strain, combined with different bait types, has been tested in many different settings, but not yet in northern Africa. Overall, bait consumption and preference were similar in other studies using the same materials (bait type and sachet). The intestine bait had the highest acceptance rate (97.6%, 95%CI: 87.4-99.9), followed by the egg bait (83.0%, 95%CI: 69.2-92.4). Only 52% (95%CI: 37.4-66.3) of the dogs showed an interest in the fish meal bait. However, considering the successful release of the contents of the sachet (blue-dyed water) into the oral cavity, the egg bait (65.7%, 95%CI: 47.8-80.9) scored better than the intestine bait (51.7%, 95%CI: 32.5-70.6). The dogs selected for the immunogenicity study were offered the egg bait containing a sachet filled with SPBN GASGAS (3.0 mL, 107.5 FFU/mL) or were given the same dose by direct oral administration (d.o.a.). In addition, several dogs were vaccinated by the parenteral route (s.c.) using a commercially available inactivated rabies vaccine. Unfortunately, due to the COVID-19 pandemic and subsequent travel restrictions, it was not possible to collect blood samples directly after vaccination. The blood samples were collected pre-vaccination and on five occasions between 450 and 1088 days post vaccination. The seroconversion rate, as determined for rabies-virus-neutralizing antibodies by the FAVN test, was significantly lower than that found for binding antibodies, as determined by ELISA, for all blood samples collected post vaccination. No treatment effect (bait, d.o.a., s.c.) could be seen in the seroconversion rate. At 15 months post vaccination, 84.2% of the dogs offered vaccine bait still tested sero-positive in ELISA. Only after 3 years was a clear drop in the seroconversion rate observed in all three treatment groups. This study confirms the long-term immunogenicity of the oral rabies vaccine SPBN GASGAS in dogs under field conditions.

Influence of habitat and baiting strategy on oral rabies vaccine bait uptake by raccoons in the southeastern United States

Oral rabies vaccination (ORV) is the primary tool for landscape level control and elimination of rabies virus in terrestrial wildlife species. However, there is currently a limited understanding of how different baiting strategies influence raccoon (Procyon lotor) uptake of ORV baits in non-agricultural habitats in the Southeastern United States, which may hinder the refinement of ORV management for raccoons in this region. Using a combination of new and existing data, we investigated the role of baited area (0.16 vs 3 km2), bait density (75 vs 150 baits/km2) and season (spring vs fall) on placebo ORV bait uptake by raccoons in four rural, non-agricultural habitats in the southeastern United States (bottomland hardwood forest, upland pine forest, riparian forest, and isolated wetlands). Increasing the baited area to 3 km2 increased the proportion of raccoons that consumed baits by 140 % in riparian forests and decreased the proportion consuming baits by 70 % in bottomland hardwood forests. A greater proportion of raccoons consumed baits in riparian habitat in spring compared to fall, but bait density did not influence uptake in either season in this habitat. Increasing the bait density during spring in bottomland hardwoods increased the proportion of raccoons that consumed baits by 270 %, but there was no effect of increasing bait density in bottomland hardwoods during fall. We suggest that variation in habitat contiguity and seasonal resource availability influence how raccoons utilize these habitats which in turn impacts habitat-specific ORV bait uptake. The estimated proportion of raccoons that consumed baits did not exceed 60 % for any treatment, and for most treatments was less than 40 %. These low uptake rates indicate a need for research into additional strategies to maximize raccoon uptake of ORV baits across rural, non-agricultural southeastern landscapes.

Managing Rabies Cases with a One Health Approach in Various Countries: Literature Review

Introduction: More people die from rabies than from other zoonotic diseases worldwide each year, with an estimated 60,000 deaths attributable to the disease. The management of rabies epidemics in humans and animals is the main goal of the One Health approach's implementation. Reducing the risk of animal-to-human rabies transmission not only lessens the requirement for post-exposure vaccinations but also lessens the financial burden of rabies management in people. Objective: This review aims to provide a general overview and comparison of rabies control programs in various countries using the One Health approach. Method: PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-analyses) is used in the literature review. Using the Science Direct, Scopus, and Pubmed databases covering the years 2012–2022, look up library resources. Result: The results of the literature search with the keywords control, one health approach, and rabies were screened again according to the predetermined inclusion criteria and the publication time range of 2012–2022 until 10 suitable journals were obtained. With financial assistance from the European Union, a number of European nations initiated oral rabies vaccination (ORV) programs in foxes. The vaccine was given in bait form, effectively controlling vulpine rabies. The creation of ORV demonstrates that oral rabies vaccination for wildlife in Serbia was effective and was marked by a rise in the use of vaccine bait as well as an increase in the animal's immunological response. Consequently, until 2018, fewer instances of rabies were documented. Conclusion: With multisectoral support from partners in the government and non-government sectors, implementing One Health is one of the best ways to reduce rabies and guarantee community engagement and knowledge.

The practice of creating buffer zones in anti-epizootic measures for rabies using the example of the border zone with Finland

One of the important tasks of veterinary medicine in the Russian Federation is the implementation of measures to prevent and eliminate infectious animal diseases[2]. Animal rabies is a zoonotic transboundary disease. It is characterized by natural focality, and wild carnivores, in particular the fox, are considered a reservoir of the rabies pathogen. Since the end of the twentieth century, oral rabies vaccines have been used to prevent rabies in Western Europe and the United States [1,3].This article presents the results of research work in 2003-2009. to create a buffer zone against animal rabies on the border with Finland by oral vaccination of wild carnivores in the Leningrad region, the Republic of Karelia. Live vaccines were used in the work: "FUCHSORAL" (Germany) and domestic ones - "SINRAB" (FGBU "ARRIAH, Vladimir) and its analogue - the vaccine "ORALRABIVAK" produced by OJSC "PZB" (Pokrov).In the Leningrad region and the Republic of Karelia in 2003, the FUCHSORAL vaccine (Germany) was used once, and in subsequent years, double annual vaccination was carried out with domestic vaccines. In Finland, people were constantly vaccinated with the oral rabies vaccine “FUCHSORAL” (Germany), from the “SAD B19” strain [4]We carried out annual 2-fold vaccination (in spring and autumn) of wild carnivores, in accordance with the instructions for use of vaccines, at air temperatures from +2 to +8 C in a zone 50-80 km wide from the border for 6 years. The number of blood serum samples containing a level of rabies virus-neutralizing antibodies sufficient to protect against rabies in the Republic of Karelia increased from 0% to 80%, and in the Leningrad region. from 0% to 70%.As a result of the implementation of planned work in the period 2003-2009. to prevent rabies among wild carnivores in the Leningrad region and the Republic of Karelia, epizootic freedom from rabies was achieved, satisfying the neighboring country.

A Global Perspective on Oral Vaccination of Wildlife against Rabies.

The long-term mitigation of human-domestic animal-wildlife conflicts is complex and difficult. Over the last 50 yr, the primary biomedical concepts and actualized collaborative global field applications of oral rabies vaccination to wildlife serve as one dramatic example that revolutionized the field of infectious disease management of free-ranging animals. Oral vaccination of wildlife occurred in diverse locales within Africa, Eurasia, the Middle East, and North America. Although rabies is not a candidate for eradication, over a billion doses of vaccine-laden baits distributed strategically by hand, at baiting stations, or via aircraft, resulted in widespread disease prevention, control, or local disease elimination among mesocarnivores. Pure, potent, safe, and efficacious vaccines consisted of either modified-live, highly attenuated, or recombinant viruses contained within attractive, edible baits. Since the late 1970s, major free-ranging target species have included coyotes (Canis latrans), foxes (Urocyon cinereoargenteus; Vulpes vulpes), jackals (Canis aureus; Lupulella mesomelas), raccoons (Procyon lotor), raccoon dogs (Nyctereutes procyonoides), and skunks (Mephitis mephitis). Operational progress has occurred in all but the latter species. Programmatic evaluations of oral rabies vaccination success have included: demonstration of biomarkers incorporated within vaccine-laden baits in target species as representative of bait contact; serological measurement of the induction of specific rabies virus neutralizing antibodies, indicative of an immune response to vaccine; and most importantly, the decreasing detection of rabies virus antigens in the brains of collected animals via enhanced laboratory-based surveillance, as evidence of management impact. Although often conceived mistakenly as a panacea, such cost-effective technology applied to free-ranging wildlife represents a real-world, One Health application benefiting agriculture, conservation biology, and public health. Based upon lessons learned with oral rabies vaccination of mesocarnivores, opportunities for future extension to other taxa and additional diseases will have far-reaching, transdisciplinary benefits.

Oral Rabies Vaccination of Raccoons (Procyon lotor) across a Development Intensity Gradient in Burlington, Vermont, USA, 2015-2017.

Management of the raccoon rabies virus variant in North America is conducted primarily using oral rabies vaccination (ORV). When a sufficient proportion of the population is vaccinated (∼60%), rabies transmission can be eliminated. To date, ORV programs have successfully controlled and eliminated raccoon rabies in rural areas, but there has been less success in urban areas. We studied the proportions of rabies virus neutralizing antibodies (RVNA) in a raccoon (Procyon lotor) population during a 3-yr ORV trial in developed areas of Burlington, Vermont, US. We used a modified N-mixture model to estimate raccoon abundance, RVNA seroprevalence, and capture rates jointly to examine factors that relate to ORV success to better inform management. We found that raccoon abundance was lower in less-developed areas compared to urban centers. Raccoon RVNA seroprevalence decreased as population abundance increased; it increased as the average age of the population increased. Nontarget opossum (Didelphis virginiana) captures correlated with a decrease in raccoon RVNA seroprevalence in low-development areas, suggesting that they may be competing for baits. The target bait density across the entire study area was 150 baits/km2, but a hand baiting strategy was heavily concentrated on roads, resulting in uneven bait densities within sampling sites (0-484 baits/km2). Uneven bait distribution across the study area may explain low RVNA seroprevalence in some locations. Our results suggest that increases in bait density across the study area may improve RVNA seroprevalence and support annual ORV to account for raccoon population turnover.

Assessing the Efficiency of Local Rabies Vaccination Strategies for Raccoons (Procyon lotor) in an Urban Setting.

Raccoon rabies virus (RRV) has been managed using multiple vaccination strategies, including oral rabies vaccination and trap-vaccinate-release (TVR). Identifying a rabies vaccination strategy for an area is a nontrivial task. Vaccination strategies differ in the amount of effort and monetary costs required to achieve a particular level of vaccine seroprevalence (efficiency). Simulating host movement relative to different vaccination strategies in silico can provide a useful tool for exploring the efficiency of different vaccination strategies. We refined a previously developed individual-based model of raccoon movement to evaluate vaccination strategies for urban Hamilton, Ontario, Canada. We combined different oral rabies vaccination baiting (hand baiting, helicopter, and bait stations) with TVR strategies and used GPS data to parameterize and simulate raccoon movement in Hamilton. We developed a total of 560 vaccination strategies, in consultation with the Ontario Ministry of Natural Resources and Forestry, for RRV control in Hamilton. We documented the monetary costs of each vaccination strategy and estimated the population seroprevalence. Intervention costs and seroprevalence estimates were used to calculate the efficiency of each strategy to meet targets set for the purpose of RRV control. Estimated seroprevalence across different strategies varied widely, ranging from less than 5% to more than 70%. Increasing bait densities (distributed using by hand or helicopter) led to negligible increase in seroprevalence. Helicopter baiting was the most efficient and TVR was the least efficient, but helicopter-based strategies led to lower levels of seroprevalence (6-12%) than did TVR-based strategies (17-70%). Our simulations indicated that a mixed strategy including at least some TVR may be the most efficient strategy for a local urban RRV control program when seroprevalence levels >30% may be required. Our simulations provide information regarding the efficiency of different vaccination strategies for raccoon populations, to guide local RRV control in urban settings.

Chukotka as a Portal for the Rabies Introduction into Kamchatka (Systematic Review)

The aim of this review was to assess the peculiarities of distribution and epidemiological risk of rabies in the extreme northeast of Asia. The systematic review was prepared through synthesizing publications on rabies over 1860–2022 (n=22) and previously unpublished data for 2009–2023. From the late 19th century until the 1980s, rabies epizootics were consistently observed in Chukotka and Kamchatka. A correlation was found between the time of occurrence of rabies in those territories with a lag period of 1–2 years (r=0.349; p=0.054). In 2009–2023, 24 animal rabies cases were confirmed in Chukotka; rabies has not been registered in Kamchatka since 1981. Until 1982, 5 confirmed human rabies cases were described in Chukotka, as well as 4 lethal cases presumably due to rabies (Chukotka – 3, Kamchatka – 1). The similarity of the spatial distribution of epizootics in different periods of time was established. Rabies was detected mainly in the area of the permanent polar fox (Vulpes lagopus) habitation, in the coastal tundra from the mouth of the Kolyma River to the Anadyr Gulf. Outside this territory (the valleys of the Anadyr and Penzhina Rivers, the Kamchatka Peninsula), rabies was reported in red foxes (Vulpes vulpes). At present, the importance of the polar fox in the spread of rabies in Chukotka has decreased, while the significance of the red fox has increased substantially. Due to vaccination, rabies among dogs is recorded sporadically. Rabies virus isolates from Chukotka belong to the Arctic genetic lineage (Arctic-3 group), which has a circumpolar distribution. The possibility of independent circulation of the rabies virus in the Kamchatka Peninsula is doubtful because of the limited size of the red fox population. Based on the mapping, possible directions for the introduction of rabies to Kamchatka from Chukotka have been identified. Barrier oral rabies vaccination of foxes is recommended during the years of high abundance of red and polar foxes in Chukotka.

In free-roaming dog populations, does egg-based oral rabies vaccination programmes result in improved bait efficacy?

PICO Question In free-roaming dog populations, does an egg-based oral rabies vaccination (ORV) compared with meat and fish based ORVs result in improved bait efficacy? Clinical bottom line Category of research Treatment. Number and type of study designs reviewed Three non-blinded, control trials were critically reviewed. Strength of evidence Weak. Outcomes reported Variables assessed in this Knowledge Summary included the type of bait that stray dogs were most interested in, and whether or not the dog was successfully vaccinated by release of the vaccine sachet into the oral cavity. Conclusion There is weak evidence to show that stray dogs prefer egg-based baits in compared to other bait types, despite egg-based baits allowing for more successful perforation of the vaccine sachet, and hence a higher chance of a successful oral rabies vaccination. How to apply this evidence in practice The application of evidence into practice should take into account multiple factors, not limited to: individual clinical expertise, patient’s circumstances and owners’ values, country, location or clinic where you work, the individual case in front of you, the availability of therapies and resources. Knowledge Summaries are a resource to help reinforce or inform decision making. They do not override the responsibility or judgement of the practitioner to do what is best for the animal in their care.

Retrospective analysis of sero-prevalence and bait uptake estimations in foxes after oral rabies vaccination programmes at European level: Lessons learned and paths forward

Rabies caused by the Classical Rabies Virus (Lyssavirus rabies abbreviated RABV) in the European Union has been close to elimination mainly thanks to Oral Rabies Vaccination (ORV) campaigns targeting wildlife (primarily red foxes). ORV programmes co-financed by the European Commission include a monitoring-component to assess the effectiveness of the ORV campaigns at national level. This assessment is performed by a random collection of red foxes in the vaccinated areas with control of antibodies presence by serological analysis and control of bait uptake by detection of biomarkers (tetracycline incorporated into the baits) in the bones and teeth. ORV programmes aim to a vaccine coverage high enough to immunize (ideally) 70 % of the reservoir population to control the spread of the disease. European Union (EU) programmes that led to almost elimination of rabies on the territory have been traditionally found to have a bait uptake average of 70 % (EU countries; 2010–2020 period) while the seroconversion data showed an average level of 40 % (EU countries; 2010–2020 period). To better understand variations of these indicators, a study was been set up to evaluate the impact of several variables (linked to the vaccination programme itself and linked to environmental conditions) on the bait uptake and the seroconversion rate. Thus, pooling data from several countries provides more powerful statistics and the highest probability of detecting trends. Results of this study advocate the use of a single serological test across the EU since data variation due to the type of test used was higher than variations due to field factors, making the interpretation of monitoring results at EU level challenging. In addition, the results indicates a negative correlation between bait uptake and maximum temperatures reached during ORV campaigns questioning the potential impact of climatic change and associated increase of temperatures on the ORV programmes efficiency. Several hypotheses requesting additional investigation are drawn and discussed in this paper.

Long-term immunity induced by SPBN GASGAS in orally vaccinated dogs is non-inferior to inactivated rabies vaccines

In a long-term immunogenicity study (1100 days post vaccination) in local Thai dogs the immune response of the oral rabies vaccine SPBN GASGAS was compared to those elicited by a commercial inactivated vaccine using immunobridging. Based on the detection of rabies virus binding (rVBA) and rabies virus neutralizing antibodies (rVNA) as measured by ELISA and Rapid Fluorescent Focus Inhibition Test (RFFIT) the long-term immune response in dogs vaccinated orally with the SPBNA GASGAS strain of rabies vaccine in a bait was non-inferior to a conventional inactivated rabies vaccine. The outcome of this study supports extending the originally claimed duration of immunity (DOI) of SPBN GASGAS after oral vaccination for dogs from 6 to 30 months.

Two Sylvatic Rabies Re-Emergences in Central-Eastern Europe over the 2021–2022 Period: An Unprecedented Situation in Recent Years

The implementations of coordinated, standardised, and sustained oral rabies vaccination (ORV) campaigns over large areas have led to the almost elimination of sylvatic rabies from the European Union (EU) territory at the approach of 2020. The annual number of rabies cases reported within EU territory indeed dropped from around 13,000 cases in 1990 to less than 10 cases over the 2017–2019 period. Unfortunately, since 2020, the EU territory has faced two major rabies re-emergence events of rabies lyssavirus in non-flying animals. The first sylvatic rabies outbreak, already described, occurred in 2021 and 2022 in Poland in the Mazowieckie voivodeship, involving the Central Europe variant, while the second one affecting Romania, Hungaria, and Slovakia, increased considerably at the end of 2022 and involved the North East Europe variant only. Thus, Hungary and Slovakia that did not record a single case since 5–7 years, respectively, faced new rabies outbreaks in 2022. This article, therefore, presents these two epidemiological events and discusses the importance and challenges of maintaining ORV programmes and immune belts in the long term, particularly in a complicated context of a pandemic affecting organisation of human societies and of geopolitical conflicts.

Biodiversity indices and Random Forests reveal the potential for striped skunk (Mephitis mephitis) fecal microbial communities to function as a biomarker for oral rabies vaccination.

Wildlife disease surveillance and monitoring poses unique challenges when assessing rates of population vaccination, immunity, or infection prevalence. Non-invasively detected biomarkers can help reduce risk to both animal and field personnel during wildlife disease management activities. In this study, we investigated the utility of fecal microbiome data collected from captive striped skunks (Mephitis mephitis) in predicting rabies virus vaccination and infection status. We sequenced the hypervariable region 4 (V4) of the bacterial 16S gene and estimated alpha and beta diversity across timepoints in three groups of skunks: vaccination then rabies virus infection, sham vaccination then rabies virus infection, and rabies virus infected without vaccination. Alpha diversity did not differ among treatment groups but beta diversity between treatments was statistically significant. The phyla Firmicutes and Proteobacteria were dominant among all samples. Using Random Forests, we identified operational taxonomic units (OTUs) that greatly influenced classification of fecal samples into treatment groups. Each of these OTUs was correlated with fecal volatile organic compounds detected from the samples for companion treatment groups in another study. This research is the first to highlight striped skunk microbiome biodiversity as a vaccination biomarker which pushes the frontier on alternative methods for surveillance and monitoring of vaccination and disease in wildlife populations.