Development and characterization of a novel nanobody with SRMV neutralizing activity.

Peste des petits ruminants (PPR) is an acute, contact infectious disease caused by the small ruminant morbillivirus (SRMV), and its morbidity in goats and sheep can be up to 100% with significant mortality. Nanobody generated from camelid animals such as alpaca has attracted wide attention because of its unique advantages compared with conventional antibodies. The main objective of this study was to produce specific nanobodies against SRMV and identify its characteristics. To obtain the coding gene of SRMV-specific nanobodies, we first constructed an immune phage-displayed library from the VHH repertoire of alpaca that was immunized with SRMV-F and -H proteins. By using phage display technology, the target antigen-specific VHHs can be obtained after four consecutive rounds of biopanning. Results showed that the size of this VHH library was 2.26 × 1010 CFU/mL and the SRMV-F and -H specific phage particles were greatly enriched after four rounds of biopanning. The positive phage clones were selected and sequenced, and total of five independent different sequences of SRMV-specific nanobodies were identified. Subsequently, the DNA fragments of the five nanobodies were cloned into E. coli BL21(DE3), respectively, and three of them were successfully expressed and purified. Specificity and affinity towards inactivated SRMV of these purified nanobodies were then evaluated using the ELISA method. Results demonstrated that NbSRMV-1-1, NbSRMV-2-10, and NbSRMV-1-21 showed no cross-reactivity with other antigens, such as inactivated BTV, inactivated FMDV, His-tag labeled protein, and BSA. The ELISA titer of these three nanobodies against inactivated SRMV was up to 1:1000. However, only NbSRMV-1-21 displayed SRMV neutralizing activity at a maximum dilution of 1:4. The results indicate that the nanobodies against SRMV generated in this study could be useful in future applications. This study provided a novel antibody tool and laid a foundation for the treatment and detection of SRMV.

Epidemiology of peste des petits ruminants in selected districts of Borena zone, Ethiopia.

BACKGROUND: Peste des petits ruminant (PPR) is a contagious disease caused by the peste des petits ruminants virus (PPRV). The disease poses a significant economic threat to small ruminant production in Ethiopia, particularly to the striving pastoral production system. A cross-sectional study was conducted to estimate the seroprevalence and associated risk factors of PPR in the small ruminants of the Borena Zone. A total of 384 serum samples were collected randomly from sheep and goats and examined for the presence of PPRV antibodies using competition enzyme-linked immune sorbent assay (c-ELISA). Additionally, a retrospective analysis of five years of outbreak data was performed to provide insight into the spatial and temporal distribution of the disease. RESULTS: The seroprevalence of PPRV antibodies in nonvaccinated, vaccinated, and unknown vaccination status of small ruminants in this study was found to be 32.1%, 68.8%, and 45.5%, respectively. Multivariable logistic analysis revealed a statistically significant association between PPRV seropositivity and several factors, including age, animal origin, flock size, and veterinary services status. A retrospective analysis revealed 53 PPR outbreaks in the Borena Zone from 2018 to 2022, exacerbated by low vaccination coverage relative to the at-risk animal population. CONCLUSION: The study revealed significant gaps in current vaccination efforts, with herd immunity levels falling below the FAO-WOAH recommended threshold of 80%. Despite Ethiopia's ambitious goal to eradicate PPR by 2027, the frequent outbreaks and insufficient herd immunity highlight the inadequacy of the existing strategies. To effectively move toward eradication, Ethiopia must align its approach with the global PPR eradication framework, which emphasizes a comprehensive strategy that includes diagnostics, surveillance, prevention, and the establishment of a robust veterinary regulatory system, rather than relying solely on vaccination. Overcoming logistical challenges, improving vaccination coverage, and optimizing the timing of vaccination campaigns, especially in hard-to-reach areas, will be crucial for reducing outbreaks and making progress toward eradication.

Flock level socio-economic and other associated risk factors for Peste des petits ruminants (PPR) exposure in sheep and goats in Madhya Pradesh state, India.

To effectively control and eradicate PPR, the comprehensive understanding of risk factors associated with PPR exposure is vital. Hence, this study investigated socioeconomic and other associated risk determinants for PPR exposure at flock level in sheep and goats in a non-vaccination programme implemented Madhya Pradesh state India. A total of 410 sheep and goat flocks, comprised mostly of goats but also some mixed flocks, were surveyed during 2016 using a multistage random sampling procedure. Further, 230 blood samples were also collected from the farmers-reported PPR affected flocks and sera were tested using c-ELISA to confirm PPR exposure. The primary data on socioeconomic factors, farm management factors, health status, vaccination details and other epidemiological risk factors were collected from flock owners and descriptive statistics, chi-square analysis and logistic regression models were fitted to identify the significant risk factors for PPR incidence. The farmer's education, flock size, rearing pattern, and awareness of PPR vaccination were found to be significant pre-disposing risk factors for PPR exposure in the flocks. Hence, the control and eradication strategy need to be designed comprehensively considering the key social factors like education and vaccination awareness along with other flock level risk factors to eradicate PPR by 2030 in consonance with the global plan.

Pathogenesis of wild-type- and vaccine-based recombinant peste des petits ruminants virus (PPRV) expressing EGFP in experimentally infected domestic goats.

Peste des petits ruminants virus (PPRV) is a highly contagious morbillivirus related to measles and canine distemper virus, mostly affecting small ruminants. The corresponding PPR disease has a high clinical impact in goats and is characterized by fever, oral and nasal erosions, diarrhoea and pneumonia. In addition, massive infection of lymphoid tissues causes lymphopaenia and immune suppression. This results in increased susceptibility to secondary bacterial infections, explaining the observed high mortality in some outbreaks. We studied the pathogenesis of PPR by experimental inoculation of Dutch domestic goats with a recombinant virulent PPRV strain modified to express EGFP and compared it to an EGFP-expressing vaccine strain of PPRV. After intratracheal inoculation with virulent PPRV, animals developed fever, viraemia and leucopaenia, and shed virus from the respiratory and gastro-intestinal tracts. Macroscopic evaluation of fluorescence at the peak of infection 7 days post-inoculation (dpi) showed prominent PPRV infection of the respiratory tract, lymphoid tissues, gastro-intestinal tract, mucosae and skin. Flow cytometry of PBMCs collected over time demonstrated a cell-associated viraemia mediated by infected lymphocytes. At 14 dpi, pathognomonic zebra stripes were detected in the mucosa of the large intestine. In contrast, vaccine strain-inoculated goats remained largely macroscopically fluorescence negative and did not present clinical signs. A low-level viraemia was detected by flow cytometry, but at necropsy no histological lesions were observed. Animals from both groups seroconverted as early as 7 dpi and sera efficiently neutralized virulent PPRV in vitro. Combined, this work presents a study of the pathogenesis of wild type- and vaccine-based PPRV in its natural host. This study shows the strength of recombinant EGFP-expressing viruses in fluorescence-guided pathogenesis studies.

Creation of poxvirus expressing foot-and-mouth and peste des petits ruminant disease virus proteins.

OBJECTIVE: Foot-and-mouth disease (FMD) and Peste des petits ruminant disease (PPR) are acute and severe infectious diseases of sheep and are listed as animal diseases for compulsory immunization. However, there is no dual vaccine to prevent these two diseases. The Modified Vaccinia virus Ankara strain (MVA) has been widely used in the construction of recombinant live vector vaccine because of its large capacity of foreign gene, wide host range, high safety, and immunogenicity. In this study, MVA-GFP recombinant virus skeleton was used to construct dual live vector vaccines against FMD and PPR. METHODS: The recombinant plasmid pUC57-FMDV P1-2A3CPPRV FH was synthesized and transfected into MVA-GFP infected CEF cells for homologous recombination. RESULTS: The results showed that a recombinant virus without fluorescent labeling was obtained after multiple rounds of plaque screening. The recombinant virus successfully expressed the target proteins, and the empty capsid of FMDV could be observed by transmission electron microscope (TME), and the expression levels of foreign proteins (VP1 and VP3) detected by ELISA were like those detected in FMDV-infected cells. This study laid the foundation for the successful construction of a live vector vaccine against FMD and PPR. KEY POINTS: • A recombinant MVA expressing FMDVP12A3C and PRRV HF proteins • Both the FMDV and PRRV proteins inserted into the virus were expressed • The proteins expressed by the recombinant poxvirus were assembled into VLPs.

A recombinant capripoxvirus expressing the F protein of peste des petits ruminants virus and the P12A3C of foot-and-mouth disease virus.

BACKGROUND: Peste des petits ruminants (PPR), foot-and-mouth disease (FMD) and sheep pox and goat pox are three important infectious diseases that infect goats, sheep and other small ruminants. It is well-known that the prevention of three diseases rely mainly on their individual vaccines. However, the vaccines have a variety of different disadvantages, such as short duration of immunity, increasing the number of vaccinations, and poor thermal stability. The purpose of this study is to construct a recombinant goat pox virus (rGPV) capable of expressing the F gene of PPRV and the P12A3C gene of FMDV as a live vector vaccine. RESULTS: The IRES, FMDV P12A3C and PPRV F genes into the multi-cloning site of the universal transfer plasmid pTKfpgigp to construct a recombinant transfer plasmid pTKfpgigpFiP12A3C, and transfected GPV-infected lamb testis (LT) cells with liposomes and produced by homologous recombination Recombinant GPV (rGPV/PPRVF-FMDVP12A3C, rGPV). The rGPV was screened and purified by green florescence protein (GFP) and xanthine-guanine-phosphoribosyltransferase gene (gpt) of Escherichia coli as selective markers, and the expression of rGPV in LT cells was detected by RT-PCR and immunofluorescence techniques. The results showed that the virus strain rGPV/PPRVF-FMDVP12A3C containing FMDV P12A3C and PPRV F genes was obtained. The exogenous genes FMDV P12A3C and PPRV F contained in rGPV were normally transcribed and translated in LT cells, and the expression products could specifically react with PPRV and FMDV antiserum. Then, the rGPV was intradermally inoculated with goats, the animal experiments showed that rGPV/PPRVF-FMDVP12A3C could induce high levels of specific antibodies against GPV, PPRV and FMDV. CONCLUSIONS: The constructed rGPV induced high levels of specific antibodies against GPV, PPRV and FMDV. The study provides a reference for " one vaccine with multiple uses " of GPV live vector vaccine.

Genomic characterization of peste des petits ruminants vaccine seed "45G37/35-k", Russia.

Production of peste des petits ruminants (PPR) vaccines in Russia is based on two attenuated virus strains ("45G37/35-k" and "ARRIAH") of common origin. Here, the identity of the strain PPRV/45G37/35-k was investigated using a full genome, Illumina deep sequencing approach. Phylogenomic analysis showed that PPRV/45G37/35-k belongs to the same lineage as the widely used PPRV vaccine strain Nigeria/75/1 (lineage II). However, 248 nucleotide differences separate the genomes of these vaccine strains, indicating that the PPRV vaccine strains produced in Russia are new strains not yet recognised by the World Organization for Animal Health (WOAH). Detailed information on the safety and efficacy of these vaccines should be provided to the WOAH before further national and international distribution.

Effectiveness and profitability of preventive veterinary interventions in controlling infectious diseases of ruminant livestock in sub-Saharan Africa: a scoping review.

Agriculture in general, and livestock production in particular, serve as a livelihood source for many people in sub-Saharan Africa (SSA). In many settings, lack of control of infectious diseases hampers livestock productivity, undermining the livelihood of rural populations. This scoping review sought to identify veterinary interventions previously evaluated as well as their relative effectiveness in controlling infectious livestock diseases. To be included, papers had to be written in English, German or French, and had to describe the effectiveness and/or profitability of preventive veterinary intervention(s) against anthrax, blackleg, bovine tuberculosis, brucellosis, contagious bovine pleuropneumonia, contagious caprine pleuropneumonia, foot-and-mouth disease, goat pox, lumpy skin disease, pasteurellosis, peste des petits ruminants, and/or sheep pox in any SSA country. Of the 2748 publications initially screened, 84 met our inclusion criteria and were analyzed. Most of the studies (n = 73, 87%) evaluated the effectiveness and/or profitability of vaccination, applied exclusively, applied jointly with, or compared to strategies like deworming, antimicrobial treatment, surveillance, feed supplementation, culling and dipping in reducing morbidity and/or mortality to livestock diseases. The effectiveness and/or profitability of antimicrobial treatment (n = 5), test and slaughter (n = 5), and use of lay animal health workers (n = 1) applied exclusively, were evaluated in the other studies. Vaccination was largely found to be both effective and with positive return on investment. Ineffective vaccination was mainly due to loss of vaccine potency under unfavorable field conditions like adverse weather events, cold chain failure, and mismatch of circulating pathogen strain and the vaccines in use.In summary, vaccination is the most effective and profitable means of controlling infectious livestock diseases in SSA. However, to achieve effective control of these diseases, its implementation must integrate pathogen surveillance, and optimal vaccine delivery tools, to overcome the reported field challenges.

Epitope-Containing Short Peptides Capture Distinct IgG Serodynamics That Enable Differentiating Infected from Vaccinated Animals for Live-Attenuated Vaccines.

Differentiating infected from vaccinated animals (DIVA) strategies have been central enabling techniques in several successful viral disease elimination programs. However, owing to their long and uncertain development process, no DIVA-compatible vaccines are available for many important diseases. We report herein a new DIVA strategy based on hybrid protein-peptide microarrays which can theoretically work with any vaccine. Leading from our findings from peste des petits ruminants (PPR) virus, we found 4 epitope-containing short peptides (ECSPs) which have distinct IgG serodynamics: anti-ECSP IgGs only exist for 10 to 60 days postvaccination (dpv), while anti-protein IgGs remained at high levels for >1,000 dpv. These data enabled the design of a DIVA diagnostic microarray containing 4 ECSPs and 3 proteins, which, unlike competitive enzyme-linked immunosorbent assay (cELISA) and virus neutralization tests (VNTs), enables ongoing monitoring of serological differences between vaccinated individuals and individuals exposed to the pathogen. For 25 goats after 60 dpv, 13 were detected with positive anti-ECSP IgGs, indicating recent infections in vaccinated goat herds. These DIVA diagnostic microarrays will almost certainly facilitate eradication programs for (re)emerging pathogens and zoonoses.IMPORTANCE Outbreaks of infectious diseases caused by viruses, such as pseudorabies (PR), foot-and-mouth disease (FMD), and PPR viruses, led to economic losses reaching billions of dollars. Both PR and FMD were eliminated in several countries via large-scale vaccination programs using DIVA-compatible vaccines, which lack the gE protein and nonstructural proteins, respectively. However, there are still extensive challenges facing the development and deployment of DIVA-compatible vaccines because they are time-consuming and full of uncertainty. Further, the negative marker strategy used for DIVA-compatible vaccines is no longer functional for live-attenuated vaccines. To avoid these disadvantageous scenarios, a new strategy is desired. Here, we made the exciting discovery that different IgG serodynamics can be monitored when using protein-based assays versus arrays comprising ECSPs. This DIVA microarray strategy should, in theory, work for any vaccine.

A dynamic model of transmission and elimination of peste des petits ruminants in Ethiopia.

Peste des petits ruminants (PPR), a devastating viral disease of sheep and goats, has been targeted by the global community for eradication within the next 15 years. Although an efficacious attenuated live vaccine is available, the lack of knowledge about the transmission potential of PPR virus (PPRV) may compromise eradication efforts. By fitting a metapopulation model simulating PPRV spread to the results of a nationwide serological survey in Ethiopia, we estimated the level of viral transmission in an endemic setting and the vaccination coverage required for elimination. Results suggest that the pastoral production system as a whole acts as a viral reservoir, from which PPRV spills over into the sedentary production system, where viral persistence is uncertain. Estimated levels of PPRV transmission indicate that viral spread could be prevented if the proportion of immune small ruminants is kept permanently above 37% in at least 71% of pastoral village populations. However, due to the high turnover of these populations, maintaining the fraction of immune animals above this threshold would require high vaccine coverage within villages, and vaccination campaigns to be conducted annually. Adapting vaccination strategies to the specific characteristics of the local epidemiological context and small ruminant population dynamics would result in optimized allocation of limited resources and increase the likelihood of PPR eradication.

Comparison of the Immunogenicities and Cross-Lineage Efficacies of Live Attenuated Peste des Petits Ruminants Virus Vaccines PPRV/Nigeria/75/1 and PPRV/Sungri/96.

Peste des petits ruminants (PPR) is a severe disease of goats and sheep that is widespread in Africa, the Middle East, and Asia. Several effective vaccines exist for the disease, based on attenuated strains of the virus (PPRV) that causes PPR. While the efficacy of these vaccines has been established by use in the field, the nature of the protective immune response has not been determined. In addition, while the vaccine derived from PPRV/Nigeria/75/1 (N75) is used in many countries, those developed in India have never been tested for their efficacy outside that country. We have studied the immune response in goats to vaccination with either N75 or the main Indian vaccine, which is based on isolate PPRV/India/Sungri/96 (S96). In addition, we compared the ability of these two vaccines, in parallel, to protect animals against challenge with pathogenic viruses from the four known genetic lineages of PPRV, representing viruses from different parts of Africa, as well as Asia. These studies showed that, while N75 elicited a stronger antibody response than S96, as measured by both enzyme-linked immunosorbent assay and virus neutralization, S96 resulted in more pronounced cellular immune responses, as measured by virus antigen-induced proliferation and interferon gamma production. While both vaccines induced comparable numbers of PPRV-specific CD8+ T cells, S96 induced a higher number of CD4+ T cells specifically responding to virus. Despite these quantitative and qualitative differences in the immune responses following vaccination, both vaccines gave complete clinical protection against challenge with all four lineages of PPRV.IMPORTANCE Despite the widespread use of live attenuated PPRV vaccines, this is the first systematic analysis of the immune response elicited in small ruminants. These data will help in the establishment of the immunological determinants of protection, an important step in the development of new vaccines, especially DIVA vaccines using alternative vaccination vectors. This study is also the first controlled test of the ability of the two major vaccines used against virulent PPRV strains from all genetic lineages of the virus, showing conclusively the complete cross-protective ability of these vaccines.

Expression kinetics of ISG15, IRF3, IFNγ, IL10, IL2 and IL4 genes vis-a-vis virus shedding, tissue tropism and antibody dynamics in PPRV vaccinated, challenged, infected sheep and goats.

Here, we studied the in vivo expression of Th1 (IL2 and IFN gamma) and Th2 (IL4 and IL10) - cytokines and antiviral molecules - IRF3 and ISG15 in peripheral blood mononuclear cells in relation to antigen and antibody dynamics under Peste des petits ruminants virus (PPRV) vaccination, infection and challenge in both sheep and goats. Vaccinated goats were seropositive by 9 days post vaccination (dpv) while in sheep idiosyncratic response was observed between 9 and 14 dpv for different animals. Expression of PPRV N gene was not detected in PBMCs of vaccinated and vaccinated challenged groups of both species, but was detected in unvaccinated infected PBMCs at 9 and 14 days post infection. The higher viral load at 9 dpi coincided with the peak clinical signs of the disease. The peak in viral replication at 9 dpi correlated with significant expression of antiviral molecules IRF3, ISG15 and IFN gamma in both the species. With the progression of disease, the decrease in N gene expression also correlated with the decrease in expression of IRF3, ISG15 and IFN gamma. In the unvaccinated infected animals ISG15, IRF3, IFN gamma and IL10 expression was higher than vaccinated animals. The IFN gamma expression predominated over IL4 in both vaccinated and infected animals with the infected exhibiting a stronger Th1 response. The persistent upregulation of this antiviral molecular signature - ISG15 and IRF3 even after 2 weeks post vaccination, presumably reflects the ongoing stimulation of innate immune cells.

The Opportunity To Eradicate Peste des Petits Ruminants.

Peste des petits ruminants (PPR) is a highly infectious disease of sheep and goats that is caused by PPR virus, a member of the genus Morbillivirus that includes the viruses that cause rinderpest (RP) in cattle. RP was the first animal disease to be globally eradicated in 2011 and is only the second disease, after smallpox, to have ever been eradicated. PPR is one of the principal constraints to small ruminant production in Africa, Asia, and the Middle East. The epidemiology of PPR and RP as well as the technologies available for their diagnosis and control are similar. The conditions that favored the eradication of RP are also largely present for PPR. In this work, we outline the evolving strategy for eradication in light of current opportunities and challenges, as well as the lessons from other eradication programs in animal and human health. The global PPR situation and technology for its control are summarized. A strategy based on the lessons from previous eradication efforts that integrate epidemiology, social science, and economics as tools to target and motivate vaccination is summarized. Major aspects of the cost and benefit-cost analysis of the indicated program are presented. The overall undiscounted cost of eradication was estimated as $3.1 billion, and the benefit-cost ratio for the most likely scenario was estimated at 33.8. We close with a discussion of the possible next steps.

Concurrent vaccination of goats with foot and mouth disease (FMD) and peste des petits ruminants (PPR) booster vaccines.

Foot and mouth disease (FMD) remains subclinical and self-limiting in small ruminants, but risk of spread of infection to susceptible cohorts is of great epidemiological significance; therefore, small ruminants must be included in vaccination campaigns in FMD endemic regions. Three groups of goats already immunized against peste des petits ruminants (PPR) were vaccinated with FMD and PPR vaccines alone or concurrently. The specific antibody response against three FMD virus strains and PPR virus were evaluated by competitive enzyme-linked immunosorbent assay (cELISA). Goats concurrently vaccinated with PPR + FMD vaccines had significantly (p < 0.05) higher antibody titers to two serotypes of FMD virus at 28, 45, and 60 days post-immunization compared to goats vaccinated with FMD vaccine alone, while goats vaccinated with PPR vaccines alone or PPR + FMD vaccines concurrently showed similar antibody kinetics against PPR virus up till 60 days post-vaccination. Overall, antibody kinetic curves for all three tested strains of FMD virus and PPR virus were similar in vaccinated groups during the course of experiment.

Future research to underpin successful peste des petits ruminants virus (PPRV) eradication.

Peste des petits ruminants virus (PPRV) is a significant pathogen of small ruminants and is prevalent in much of Africa, the Near and Middle East and Asia. Despite the availability of an efficacious and cheap live-attenuated vaccine, the virus has continued to spread, with its range stretching from Morocco in the west to China and Mongolia in the east. Some of the world's poorest communities rely on small ruminant farming for subsistence and the continued endemicity of PPRV is a constant threat to their livelihoods. Moreover, PPRV's effects on the world's population are felt broadly across many economic, agricultural and social situations. This far-reaching impact has prompted the Food and Agriculture Organization of the United Nations (FAO) and the World Organisation for Animal Health (OIE) to develop a global strategy for the eradication of this virus and its disease. PPRV is a morbillivirus and, given the experience of these organizations in eradicating the related rinderpest virus, the eradication of PPRV should be feasible. However, there are many critical areas where basic and applied virological research concerning PPRV is lacking. The purpose of this review is to highlight areas where new research could be performed in order to guide and facilitate the eradication programme. These areas include studies on disease transmission and epidemiology, the existence of wildlife reservoirs and the development of next-generation vaccines and diagnostics. With the support of the international virology community, the successful eradication of PPRV can be achieved.

Determination of the minimum fully protective dose of adenovirus-based DIVA vaccine against peste des petits ruminants virus challenge in East African goats.

Peste des petits ruminants virus (PPRV) causes an economically important disease of sheep and goats, primarily in developing countries. It is becoming the object of intensive international control efforts. Current vaccines do not allow vaccinated and infected animals to be distinguished (no DIVA capability). We have previously shown that recombinant, replication-defective, adenovirus expressing the PPRV H glycoprotein (AdH) gives full protection against wild type PPRV challenge. We have now tested lower doses of the vaccine, as well as AdH in combination with a similar construct expressing the PPRV F glycoprotein (AdF). We show here that, in a local breed of goat in a country where PPR disease is common (Kenya), as little as 10(7) pfu of AdH gives significant protection against PPRV challenge, while a vaccine consisting of 10(8) pfu of each of AdH and AdF gives apparently sterile protection. These findings underline the utility of these constructs as DIVA vaccines for use in PPR control.

Peste des petits ruminants diagnosis and diagnostic tools at a glance: perspectives on global control and eradication.

Peste des petits ruminants (PPR) is a highly contagious, economically important viral disease of small ruminants, targeted for global eradication by the year 2030. The recent geographic surge in PPR virus distribution, economic implications, the success of the rinderpest eradication campaign, and ongoing national/regional efforts convinced the FAO and OIE to initiate a global PPR control and eradication strategy. Since its discovery, a series of diagnostic tools have been developed for detecting PPR virus and virus-specific antibodies. Furthermore, it is understood that diagnostic and vaccine-monitoring tools are inevitable components of the four-stage strategy of global PPR eradication from assessment to the post-eradication phase. However, these tools may not be suitable for all stages of PPR control and eradication. For instance, diagnostics such as ELISA could be used for mass screening of clinical and serum samples, whereas immunochromatographic tests can be used at the field level as a pen-side test. Yet, assays with higher sensitivity, such as RT-PCR, RT-PCR ELISA, real-time RT-PCR and LAMP are important for early diagnosis of PPR and also, theoretically, during the late stages of eradication or when sampling non-natural hosts. Moreover, during the later stages of any control program, suspected/doubtful outbreaks will have to be reconfirmed using multiple laboratory tests. Hence, diagnostics can and should be efficiently applied at different stages of the PPR control and eradication campaign based on available resources and the number of samples to be tested. This article provides an overview of the various PPR diagnostic tools and suggests where and how they should be logically applied during the different phases of global PPR control and eradication.

Livestock vaccination in India: an analysis of theory and practice among multiple stakeholders.

An effective and efficient disease prevention and control strategy is of paramount importance to improve the quality and quantity of livestock production in the Indian context. Although livestock vaccination is considered an emerging innovation of socioeconomic importance in the Indian dairy industry, the rate of adoption and diffusion of vaccination technology is very low at field level. In this context, the authors examined the efforts of the Government of India to protect livestock health and control disease, considered the lessons learnt from rinderpest eradication, looked at field practices and the reality on the ground, and studied the perceptions of multiple stakeholders with regards to the relevance, profitability and sustainability of vaccination. In this study, the authors consider policy implications for the Indian dairy industry using the responses of 360 dairy farmers, 80 research scientists and 40 extension workers in India. The study revealed that scientists and extension experts rated vaccination highly in terms of its relevance, profitability and sustainability, while the perception of farmers was less favourable. The study also observed that, even after implementation of various disease control programmes with heavy financial expenditure, there was a wide gap between farmers and scientists and between farmers and extension workers with regards to their perceptions of the relevance, profitability and sustainability of vaccination, while the gap was very narrow between scientists and extension workers. It can be concluded, therefore, that there is a need to generate innovations for disease control that are perceived as relevant, profitable and sustainable so as to encourage higher levels of diffusion and adoption at field level. This study recommends that farmers partner with researchers and extension workers to ensure effective generation and transfer of new dairying technologies, leading to higher production and productivity in the Indian dairy sector.

En Inde, l'amélioration qualitative et quantitative de la productivité des élevages passe nécessairement par la mise en place de stratégies efficaces et efficientes de prévention et de contrôle des maladies animales. Les producteurs de lait et de produits laitiers considèrent la vaccination du bétail comme une innovation importante au plan socio-économique mais le niveau d'adoption et de diffusion des technologies vaccinales demeure très faible sur le terrain. Ce constat a incité les auteurs à effectuer une étude visant à analyser les efforts déployés par le gouvernement indien pour protéger la santé du bétail et pour lutter contre les maladies, à déterminer le niveau de prise en compte des leçons de l'éradication de la peste bovine, et à décrire les pratiques et la situation concrète sur le terrain ainsi que la manière dont les diverses parties prenantes perçoivent la pertinence, la rentabilité économique et les effets dans le temps de la vaccination. Dans cette étude, les auteurs ont interrogé 360 éleveurs de vaches laitières, 80 chercheurs et 40 agents de vulgarisation en Inde afin de déterminer les effets des politiques zoosanitaires sur le secteur de l'élevage laitier indien. L'étude a montré que la pertinence, la rentabilité économique et les effets dans le temps de la vaccination étaient perçus très favorablement par les chercheurs et par les agents de vulgarisation, tandis que la perception des éleveurs était moins positive. L'étude a également permis de constater que l'écart manifeste entre la perception des éleveurs d'un côté et celle des chercheurs et des agents de vulgarisation de l'autre concernant la pertinence, la rentabilité et l'effet dans le temps de la vaccination subsistait même après la mise en oeuvre à grands frais de programmes de lutte contre les maladies animales, tandis que cet écart était minime entre les chercheurs et les agents de vulgarisation. Les auteurs concluent sur la nécessité de veiller à ce que les innovations mises en place en matière de lutte contre les maladies animales soient perçues comme pertinentes, rentables et durables, afin de promouvoir une meilleure appropriation et diffusion de ces méthodes sur le terrain. Les auteurs préconisent le recours à des partenariats entre les éleveurs, les chercheurs et les agents de vulgarisation afin d'assurer une conception et un transfert efficaces des technologies dans le secteur de la production de lait et d'améliorer ainsi la production et la productivité du secteur laitier indien.

En el contexto de la India, para mejorar la producción bovina tanto en calidad como en cantidad es de capital importancia disponer de una estrategia eficaz y eficiente de prevención y control de enfermedades. Aunque la vacunación del ganado está considerada una innovación incipiente de gran importancia socioeconómica para el sector lechero del país, sobre el terreno se dan índices muy bajos de adopción y difusión de las técnicas de vacunación. En tales circunstancias, los autores examinaron las iniciativas del Gobierno de la India para proteger la salud del ganado y combatir sus enfermedades, repasaron las enseñanzas extraídas de la erradicación de la peste bovina, observaron la praxis y las realidades sobre el terreno e indagaron en la percepción que tienen numerosos interlocutores del sector de la pertinencia, rentabilidad y sostenibilidad de las vacunaciones. A partir de las respuestas aportadas por 360 productores, 80 investigadores y 40 agentes de extensión del país, los autores estudian las repercusiones normativas para la industria lechera india. El proceso puso de manifiesto que los científicos y especialistas en extensión otorgan a la vacunación un lugar de privilegio por lo que respecta a su pertinencia, rentabilidad y sostenibilidad, mientras que a los productores les merece una opinión menos positiva. Los autores observaron igualmente que, aun tras la implantación de diversos programas de lucha zoosanitaria que supusieron cuantiosas inversiones económicas, existía un gran desfase entre los productores, por un lado, y los científicos y agentes de extensión, por el otro, en cuanto a la valoración que hacían de la pertinencia, rentabilidad y sostenibilidad de las vacunaciones, mientras que las opiniones de científicos y agentes de extensión apenas diferían. Cabe concluir, por lo tanto, que para inducir sobre el terreno mayores niveles de adopción y difusión es indispensable generar innovaciones de lucha zoosanitaria que sean percibidas como algo pertinente, rentable y sostenible. Los autores recomiendan que los productores trabajen en asociación con los investigadores y agentes de extensión para lograr así que se generen y transfieran eficazmente nuevas tecnologías de producción lechera, lo que a su vez redundará en un aumento de la producción y productividad del sector lechero indio.

The global eradication of peste des petits ruminants (PPR) within 15 years--is this a pipe dream?

Gordon Scott did much to inspire the eradication of rinderpest, probably the most outstanding veterinary achievement of the twentieth century, and one currently inspiring is the proposed eradication of peste des petits ruminants (PPR), a disease of sheep and goats caused by a closely related Morbillivirus. The evolution and geographic spread of PPR along with its epidemiological characteristics are discussed and related to ways in which its spread can be reduced through the provision of diagnostic aids to sanitary livestock movement at local level. Taking a historical look at rinderpest eradication, it was shown that much could be achieved using a legislation-backed zoosanitary approach or, once developed, the build up of herd immunities in isolated populations. As the final cap to this (circa), two hundred-year-long process, major national and internationally funded vaccination programmes falling within the informal coordinatorship of the OIE and FAO showed that final eradication could be achieved with remarkable rapidity if the seat of infection was known and if appropriate national and international interventions were aimed at ending virus transmission. Were such international cooperation to be forthcoming once more, the understanding, tools and experiences now on offer suggest that PPR could be controlled and eradicated far more rapidly than rinderpest.