Sequestration and Destruction of Rinderpest Virus-Containing Material 10 Years after Eradication.

In 2021, the world marked 10 years free from rinderpest. The United Nations Food and Agriculture Organization and World Organisation for Animal Health have since made great strides in consolidating, sequencing, and destroying stocks of rinderpest virus-containing material, currently kept by only 14 known institutions. This progress must continue.

Protection of Cattle against Rinderpest by Vaccination with Wild-Type but Not Attenuated Strains of Peste des Petits Ruminants Virus.

UNLABELLED: Although rinderpest virus (RPV) has been eradicated in the wild, efforts are still continuing to restrict the extent to which live virus is distributed in facilities around the world and to prepare for any reappearance of the disease, whether through deliberate or accidental release. In an effort to find an alternative vaccine which could be used in place of the traditional live attenuated RPV strains, we have determined whether cattle can be protected from rinderpest by inoculation with vaccine strains of the related morbillivirus, peste des petits ruminants virus (PPRV). Cattle were vaccinated with wild-type PPRV or either of two established PPRV vaccine strains, Nigeria/75/1 or Sungri/96. All animals developed antibody and T cell immune responses to the inoculated PPRV. However, only the animals given wild-type PPRV were protected from RPV challenge. Animals given PPRV/Sungri/96 were only partially protected, and animals given PPRV/Nigeria/75/1 showed no protection against RPV challenge. While sera from animals vaccinated with the vaccine strain of RPV showed cross-neutralizing ability against PPRV, none of the sera from animals vaccinated with any strain of PPRV was able to neutralize RPV although sera from animals inoculated with wild-type PPRV were able to neutralize RPV-pseudotyped vesicular stomatitis virus. IMPORTANCE: Rinderpest virus has been eradicated, and it is only the second virus for which this is so. Significant efforts are still required to ensure preparedness for a possible escape of RPV from a laboratory or its deliberate release. Since RPV vaccine protects sheep and goats from PPRV, it is important to determine if the reverse is true as this would provide a non-RPV vaccine for dealing with suspected RPV outbreaks. This is probably the last in vivo study with live RPV that will be approved.

Rinderpest eradication: challenges for remaining disease free and implications for future eradication efforts.

In 2011, the World Organisation for Animal Health (OIE) and the Food and Agriculture Organization of the United Nations (FAO) declared global freedom from rinderpest, formally announcing that rinderpest virus infections had been eliminated from susceptible livestock populations. At the same time, it was recognised that rinderpest virus, and material containing rinderpest virus, remained stored in an unspecified number of facilities across the world. Although natural infections had been eliminated, there remained a risk that rinderpest could reoccur if such infectious material accidentally leaked or was intentionally released from one of these facilities into a susceptible animal population. To minimise this risk, the OIE and FAO, with the support of international partners, set in place a framework to: reduce the quantity of remaining rinderpest-virus-containing material; ensure that such material was only stored in high-security facilities; regulate any handling or manipulation of the virus; maintain vigilance amongst livestock keepers and Veterinary Services in the post-eradication era; and develop contingency plans to deal with any suspected or actual reoccurrence of rinderpest disease. In 2016, five years after the declaration of global freedom from rinderpest, official reports to the OIE show that virus and virus-containing material remain stored in 21 countries worldwide in 22 separate facilities, of which only five have been inspected and approved for holding rinderpest virus or vaccine. There is still much work to be done to further reduce the risk of a reoccurrence.

En 2011, l'Organisation mondiale de la santé animale (OIE) et l'Organisation des Nations Unies pour l'alimentation et l'agriculture (FAO) ont annoncé officiellement l'élimination de l'infection due au virus de la peste bovine dans les populations d'animaux d'élevage sensibles, déclarant ainsi la planète indemne de cette maladie. Parallèlement, les deux organisations faisaient état de l'existence d'un nombre indéterminé d'établissements dans le monde détenant des stocks du virus bovipestique ainsi que des produits contenant ce virus. Malgré l'élimination de l'infection chez ses hôtes naturels, un risque de réapparition de la peste bovine subsiste en cas de fuite accidentelle ou d'émission délibérée de ces produits infectieux dans les populations animales sensibles à partir de l'un de ces établissements. Afin de minimiser ce risque, l'OIE et la FAO soutenus par leurs partenaires internationaux ont mis en place un cadre visant plusieurs objectifs : réduire les quantités restantes de produits contenant le virus de la peste bovine dans le monde ; veiller à ce que ces produits ne soient stockés que dans des établissements de haute sécurité ; réglementer les conditions de détention et de manipulation du virus ; poursuivre la surveillance exercée par les éleveurs et les Services vétérinaires au cours de la phase post-éradication ; concevoir des plans d'urgence visant à faire face à toute réapparition suspectée ou confirmée de la peste bovine. En 2016, soit cinq ans après la déclaration de l'éradication mondiale de la peste bovine, il ressort des rapports officiels adressés à l'OIE que 21 pays détiennent encore des stocks du virus de la peste bovine ou des produits contenant ce virus, répartis en 22 établissements distincts dont seulement cinq ont fait l'objet d'une inspection et ont été dûment habilités à détenir des stocks de virus de la peste bovine ou de vaccins contre cette maladie. Il reste donc encore beaucoup à faire pour continuer à réduire le risque de réapparition de la peste bovine.

En 2011, la Organización Mundial de Sanidad Animal (OIE) y la Organización de las Naciones Unidas para la Alimentación y la Agricultura (FAO) anunciaron oficialmente que las infecciones causadas por el virus de la peste bovina habían sido eliminadas de las poblaciones sensibles de ganado, declarando así que el mundo quedaba libre de la enfermedad. Al mismo tiempo, significaron que un número no especificado de instalaciones dispersas por el mundo albergaban muestras del virus y otros productos que lo contenían. Aunque las infecciones naturales habían quedado eliminadas, subsistía el riesgo de reaparición de la peste bovina si en una de esas instalaciones se producía una fuga accidental o una liberación intencionada de material infeccioso y este entraba en contacto con una población animal sensible. Para reducir al mínimo tal riesgo, la OIE y la FAO, con apoyo de colaboradores internacionales, definieron un dispositivo encaminado a: reducir el volumen de material restante con contenido viral de la peste bovina; garantizar que ese material fuera conservado únicamente en instalaciones de alta seguridad; reglamentar toda manipulación del virus; mantener la vigilancia entre cuidadores de ganado y Servicios Veterinarios en el periodo posterior a la erradicación; y elaborar planes de emergencia para responder a toda reaparición, presunta o confirmada, de la peste bovina. En 2016, cinco años después de la declaración de ausencia mundial de peste bovina, los informes oficiales remitidos a la OIE daban fe de que había virus y productos que lo contenían en 22 instalaciones situadas en 21 países del mundo, de las que solo cinco habían sido inspeccionadas y homologadas para albergar virus de la peste bovina o vacunas contra la enfermedad. Queda pues mucho trabajo por delante para reducir en mayor medida el riesgo de reaparición.

The RNA triphosphatase domain of L protein of Rinderpest virus exhibits pyrophosphatase and tripolyphosphatase activities.

L protein of the Rinderpest virus, an archetypal paramyxovirus possesses RNA-dependent RNA polymerase activity which transcribes the genome into mRNAs as well as replicates the RNA genome. The protein also possesses RNA triphosphatase (RTPase), guanylyltransferase (GTase) and methyltransferase enzyme activities responsible for capping the mRNAs in a conventional pathway similar to that of the host pathway. Subsequent to the earlier characterization of the GTase activity of L protein and identification of the RTPase domain of the L protein, we report here, additional enzymatic activities associated with the RTPase domain. We have characterized the pyrophosphatase and tripolyphosphatase activities of the L-RTPase domain which are metal-dependent and proceed much faster than the RTPase activity. Interestingly, the mutant proteins E1645A and E1647A abrogated the pyrophosphatase and tripolyphosphatase significantly, indicating a strong overlap of the active sites of these activities with that of RTPase. We discuss the likely role of GTase-associated L protein pyrophosphatase in the polymerase function. We also discuss a possible biological role for the tripolyphosphatase activity hitherto considered insignificant for the viruses possessing such activity.

Identifying and Reducing Remaining Stocks of Rinderpest Virus.

In 2011, the world was declared free from rinderpest, one of the most feared and devastating infectious diseases of animals. Rinderpest is the second infectious disease, after smallpox, to have been eradicated. However, potentially infectious rinderpest virus material remains widely disseminated among research and diagnostic facilities across the world and poses a risk for disease recurrence should it be released. Member Countries of the World Organisation for Animal Health and the Food and Agricultural Organization of the United Nations are committed to destroying remaining stocks of infectious material or ensuring that it is stored under international supervision in a limited number of approved facilities. To facilitate this commitment and maintain global freedom from rinderpest, World Organisation for Animal Health Member Countries must report annually on rinderpest material held in their countries. The first official surveys, conducted during 2013-2015, revealed that rinderpest material was stored in an unacceptably high number of facilities and countries.

A carboxy terminal domain of the L protein of rinderpest virus possesses RNA triphosphatase activity - The first enzyme in the viral mRNA capping pathway.

The large protein L of negative-sense RNA viruses is a multifunctional protein involved in transcription and replication of genomic RNA. It also possesses enzymatic activities involved in capping and methylation of viral mRNAs. The pathway for mRNA capping followed by the L protein of the viruses in the Morbillivirus genus has not been established, although it has been speculated that these viruses may follow the unconventional capping pathway as has been shown for some viruses of Rhabdoviridae family. We had earlier shown that the large protein L of Rinderpest virus expressed as recombinant L-P complex in insect cells as well as the ribonucleoprotein complex from purified virus possesses RNA triphosphatase (RTPase) and guanylyltransferase activities, in addition to RNA dependent RNA polymerase activity. In the present work, we demonstrate that RTPase as well as nucleoside triphosphatase (NTPase) activities are exhibited by a subdomain of the L protein in the C terminal region (a.a. 1640-1840). The RTPase activity depends absolutely on a divalent cation, either magnesium or manganese. Both the RTPase and NTPase activities of the protein show dual metal specificity. Two mutant proteins having alanine mutations in the glutamic acid residues in motif-A of the RTPase domain did not show RTPase activity, while exhibiting reduced NTPase activity suggesting overlapping active sites for the two enzymatic functions. The RTPase and NTPase activities of the L subdomain resemble those of the Vaccinia capping enzyme D1 and the baculovirus LEF4 proteins.

Evidence for N7 guanine methyl transferase activity encoded within the modular domain of RNA-dependent RNA polymerase L of a Morbillivirus.

Post-transcriptional modification of viral mRNA is essential for the translation of viral proteins by cellular translation machinery. Due to the cytoplasmic replication of Paramyxoviruses, the viral-encoded RNA-dependent RNA polymerase (RdRP) is thought to possess all activities required for mRNA capping and methylation. In the present work, using partially purified recombinant RNA polymerase complex of rinderpest virus expressed in insect cells, we demonstrate the in vitro methylation of capped mRNA. Further, we show that a recombinant C-terminal fragment (1717-2183 aa) of L protein is capable of methylating capped mRNA, suggesting that the various post-transcriptional activities of the L protein are located in independently folding domains.

Different functions of the common P/V/W and V-specific domains of rinderpest virus V protein in blocking IFN signalling.

The V proteins of paramyxoviruses are composed of two evolutionarily distinct domains, the N-terminal 75 % being common to the viral P, V and W proteins, and not highly conserved between viruses, whilst the remaining 25 % consists of a cysteine-rich V-specific domain, which is conserved across almost all paramyxoviruses. There is evidence supporting a number of different functions of the V proteins of morbilliviruses in blocking the signalling pathways of type I and II IFNs, but it is not clear which domains of V are responsible for which activities and whether all these activities are required for effective blockade of IFN signalling. We have shown here that the two domains of rinderpest virus V protein have distinct functions: the N-terminal domain acted to bind STAT1, whilst the C-terminal V-specific domain interacted with the IFN receptor-associated kinases Jak1 and Tyk2. Effective blockade of IFN signalling required the intact V protein.

Rinderpest: A Disease of the Past, and a Present Threat.

Rinderpest is a highly contagious viral disease that affects ungulates such as cattle, buffalo, yak, and various wildlife species, leading to significant morbidity and mortality. The global eradication of rinderpest was successfully accomplished in 2011 through extensive vaccination efforts. Today, safeguarding against the re-emergence of rinderpest in animal populations is paramount. The Food and Agriculture Organization of the United Nations and the World Organization for Animal Health are entrusted through a series of resolutions with the responsibility to prevent the re-emergence of rinderpest in animals.

Rinderpest virus sequestration and use in posteradication era.

After the 2011 declaration of rinderpest disease eradication, we surveyed 150 countries about rinderpest virus stocks. Forty-four laboratories in 35 countries held laboratory-attenuated strains, field strains, or diagnostic samples. Vaccine and reagent production and laboratory experiments continued. Rigorous standards are necessary to ensure that stocks are kept under safe conditions.

Complete genome analysis of three live attenuated Rinderpest virus vaccine strains derived through serial passages in different culture systems.

The genomes of three South Korean Rinderpest virus vaccine strains (L72, LA77, and LA96) were analyzed in order to investigate their genetic variability. These three vaccine strains were all derived from the same virus strain origin (Fusan) through repeated passages in different culture systems. The full genome length of the three strains was 15,882 nucleotides, and the sequence similarity between the three South Korean RPV strains at the nucleotide level was 98.1 to 98.9%. The genetic distance between Nakamura III, L72, LA77, LA96, and LATC06 and the Kabete strain was greater than that between the Fusan and Kabete strains for the P, V, and C genes. The difference in pathogenicity among these strains might be due to the V gene, which has a positive (>1) selection ratio based on the analysis of synonymous (dS) and nonsynonymous (dN) substitution rates (dN/dS ratio [ω]).

Purifying selection can obscure the ancient age of viral lineages.

Statistical methods for molecular dating of viral origins have been used extensively to infer the time of most common recent ancestor for many rapidly evolving pathogens. However, there are a number of cases, in which epidemiological, historical, or genomic evidence suggests much older viral origins than those obtained via molecular dating. We demonstrate how pervasive purifying selection can mask the ancient origins of recently sampled pathogens, in part due to the inability of nucleotide-based substitution models to properly account for complex patterns of spatial and temporal variability in selective pressures. We use codon-based substitution models to infer the length of branches in viral phylogenies; these models produce estimates that are often considerably longer than those obtained with traditional nucleotide-based substitution models. Correcting the apparent underestimation of branch lengths suggests substantially older origins for measles, Ebola, and avian influenza viruses. This work helps to reconcile some of the inconsistencies between molecular dating and other types of evidence concerning the age of viral lineages.

Two distinct conformations of a rinderpest virus epitope presented by bovine major histocompatibility complex class I N*01801: a host strategy to present featured peptides.

The presentation of viral peptide epitopes to host cytotoxic T lymphocytes (CTLs) is crucial for adaptive cellular immunity to clear the virus infection, especially for some chronic viral infections. Indeed, hosts have developed effective strategies to achieve this goal. The ideal scenario would be that the peptide epitopes stimulate a broad spectrum of CTL responses with diversified T-cell receptor (TCR) usage (the TCR repertoire). It is believed that a diversified TCR repertoire requires a "featured" peptide to be presented by the host major histocompatibility complex (MHC). A featured peptide can be processed and presented in a number of ways. Here, using the X-ray diffraction method, the crystal structures of an antigenic peptide derived from rinderpest virus presented by bovine MHC class I N*01801 (BoLA-A11) have been solved, and two distinct conformations of the presented peptide are clearly displayed. A detailed analysis of the structure and comparative sequences revealed that the polymorphic amino acid isoleucine 73 (Ile73) is extremely flexible, allowing the MHC groove to adopt different conformations to accommodate the rinderpest virus peptide. This makes the peptide more featured by exposing different amino acids for T-cell recognition. The crystal structures also demonstrated that the N*01801 molecule has an unusually large A pocket, resulting in the special conformation of the P1 residue at the N terminus of the peptide. We propose that this strategy of host peptide presentation might be beneficial for creating a diversified TCR repertoire, which is important for a more-effective CTL response.

A disease-mediated trophic cascade in the Serengeti and its implications for ecosystem C.

Tree cover is a fundamental structural characteristic and driver of ecosystem processes in terrestrial ecosystems, and trees are a major global carbon (C) sink. Fire and herbivores have been hypothesized to play dominant roles in regulating trees in African savannas, but the evidence for this is conflicting. Moving up a trophic scale, the factors that regulate fire occurrence and herbivores, such as disease and predation, are poorly understood for any given ecosystem. We used a Bayesian state-space model to show that the wildebeest population eruption that followed disease (rinderpest) eradication in the Serengeti ecosystem of East Africa led to a widespread reduction in the extent of fire and an ongoing recovery of the tree population. This supports the hypothesis that disease has played a key role in the regulation of this ecosystem. We then link our state-space model with theoretical and empirical results quantifying the effects of grazing and fire on soil carbon to predict that this cascade may have led to important shifts in the size of pools of C stored in soil and biomass. Our results suggest that the dynamics of herbivores and fire are tightly coupled at landscape scales, that fire exerts clear top-down effects on tree density, and that disease outbreaks in dominant herbivores can lead to complex trophic cascades in savanna ecosystems. We propose that the long-term status of the Serengeti and other intensely grazed savannas as sources or sinks for C may be fundamentally linked to the control of disease outbreaks and poaching.

The long journey: a brief review of the eradication of rinderpest.

In 2011, the 79th General Session of the World Assembly of the World Organisation for Animal Health (OIE) and the 37th Food and Agriculture Organization of the United Nations (FAD) Conference adopted a resolution declaring the world free from rinderpest and recommending follow-up measures to preserve the benefits of this new and hard-won situation. Eradication is an achievable objective for any livestock disease, provided that the epidemiology is uncomplicated and the necessary tools, resources and policies are available. Eradication at a national level inevitably reflects national priorities, whereas global eradication requires a level of international initiative and leadership to integrate these tools into a global framework, aimed first at suppressing transmission across all infected areas and concluding with a demonstration thatthis has been achieved. With a simple transmission chain and the environmental fragility of the virus, rinderpest has always been open to control and even eradication within a zoosanitary approach. However, in the post-1945 drive for more productive agriculture, national and global vaccination programmes became increasingly relevant and important. As rinderpest frequently spread from one region to another through trade-related livestock movements, the key to global eradication was to ensure that such vaccination programmes were carried out in a synchronised manner across all regions where the disease was endemic - an objective to which the European Union, the United States Agency for International Development, the International Atomic Energy Agency, the African Union-Interafrican Bureau of Animal Resources, FA0 and OIE fully subscribed. This article provides a review of rinderpest eradication, from the seminal work carried out by Giovanni Lancisi in the early 18th Century to the global declaration in 2011.

[Morbilliviruses].

The genus Morbillivirus in the family Paramyxoviridae contains many pathogens, which are important for medicine or veterinary medicine. Because each morbillivirus has restricted host range and serologically monotypic, the virus infection and transmission is effectively controlled by vaccinations and surveillance. Rinderpest virus has been eradicated in 2011, and elimination of measles virus progresses worldwide. Recently, a new cell receptor for measles virus, nectin4 was identified. Both SLAM, a molecule expressing on immune cells, and nectin4, a molecule expressing on epithelial cells, are important to infectivity and pathogenicity of the virus.

History of measles.

Measles is a highly contagious viral disease transmitted by aerosols through human-to-human contact. It is often considered as a benign disease, although mortality remains high in developing countries (>5%). Frequent complications (diarrhea, otitis, pneumonia, encephalitis) can be observed. The disease mainly affects young children from 5 to 6 months of age with a mortality peak in the first three years of life. The Persian physician Rhazes gave the first clinical description of the disease in the 10th century, clearly differentiating it from smallpox. Measles spread worldwide from the Renaissance. Its epidemiology was remarkably studied in 1846 by a Danish physician, Peter Panum, during an epidemic in the Faroe Islands. The viral nature of this disease was demonstrated in 1911 and the virus was identified in 1954 by Thomas Peebles and John Enders. It is a morbillivirus (family Paramyxoviridae), also responsible for rinderpest (ovine, bovine), distemper (canine, feline), and epidemic diseases of dolphins, porpoises and seals. The current measles virus appeared recently from the rinderpest virus around the 6th century BCE. It has adapted perfectly to the human species, becoming strictly human, without animal reservoirs. A live attenuated vaccine was developed in 1958 by Enders' team after numerous passages in cell cultures. The vaccine was licensed in the United States in 1963 and is used on a large scale by the WHO throughout the world. This highly effective and well-tolerated vaccine has greatly reduced the number of measles cases and saved millions of lives. Measles remains a major public health concern, causing over 100,000 deaths per year worldwide. Today, the most affected continents remain Africa, South America and Asia.

Simultaneous detection of Rift Valley Fever, bluetongue, rinderpest, and Peste des petits ruminants viruses by a single-tube multiplex reverse transcriptase-PCR assay using a dual-priming oligonucleotide system.

The aim of this study was to develop a highly sensitive and specific one-step multiplex reverse transcriptase PCR assay for the simultaneous and differential detection of Rift Valley Fever virus (RVFV), bluetongue virus (BTV), rinderpest virus (RPV), and Peste des petits ruminants virus (PPRV). These viruses cause mucosal lesions in cattle, sheep, and goats, and they are difficult to differentiate from one another based solely on their clinical presentation in suspected disease cases. In this study, we developed a multiplex reverse transcriptase PCR to detect these viruses using a novel dual-priming oligonucleotide (DPO). The DPO contains two separate priming regions joined by a polydeoxyinosine linker, which blocks extension of nonspecifically primed templates and consistently allows high PCR specificity even under less-than-optimal PCR conditions. A total of 19 DPO primers were designed to detect and discriminate between RVFV, BTV, RPV, and PPRV by the generation of 205-, 440-, 115-, and 243-bp cDNA products, respectively. The multiplex reverse transcriptase PCR described here enables the early diagnosis of these four viruses and may also be useful as part of a testing regime for cattle, sheep, or goats exhibiting similar clinical signs, including mucosal lesions.