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.

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.

[Effects of the periodical spread of rinderpest on famine, epidemic, and tiger disasters in the late 17th Century].

This study clarifies the causes of the repetitive occurrences of such phenomena as rinderpest, epidemic, famine, and tiger disasters recorded in the Joseon Dynasty Chronicle and the Seungjeongwon Journals in the period of great catastrophe, the late 17th century in which the great Gyeongsin famine (1670~1671) and the great Eulbyeong famine (1695~1696) occurred, from the perspective that they were biological exchanges caused by the new arrival of rinderpest in the early 17th century. It is an objection to the achievements by existing studies which suggest that the great catastrophes occurring in the late 17th century are evidence of phenomena in a little ice age. First of all, rinderpest has had influence on East Asia as it had been spread from certain areas in Machuria in May 1636 through Joseon, where it raged throughout the nation, and then to the west part of Japan. The new arrival of rinderpest was indigenized in Joseon, where it was localized and spread periodically while it was adjusted to changes in the population of cattle with immunity in accordance with their life spans and reproduction rates. As the new rinderpest, which showed high pathogenicity in the early 17th century, was indigenized with its high mortality and continued until the late 17th century, it broke out periodically in general. Contrastively, epidemics like smallpox and measles that were indigenized as routine ones had occurred constantly from far past times. As a result, the rinderpest, which tried a new indigenization, and the human epidemics, which had been already indigenized long ago, were unexpectedly overlapped in their breakout, and hence great changes were noticed in the aspects of the human casualty due to epidemics. The outbreak of rinderpest resulted in famine due to lack of farming cattle, and the famine caused epidemics among people. The casualty of the human population due to the epidemics in turn led to negligence of farming cattle, which constituted factors that triggered rage and epidemics of rinderpest. The more the number of sources of infection and hosts with low immunity increased, the more lost human resources and farming cattle were lost, which led to a great famine. The periodic outbreak of the rinderpester along with the routine prevalence of various epidemics in the 17thcentury also had influenced on domestic and wild animals. Due to these phenomenon, full-fledged famines occurred that were incomparable with earlier ones. The number of domestic animals that were neglected by people who, faced with famines, were not able to take care of them was increased, and this might have brought about the rage of epidemics like rinderpest in domestic animals like cattle. The great Gyeongsin and Eulbyeong famines due to reoccurrence of the rinderpest in the late 17th century linked rinderpester, epidemics and great famines so that they interacted with each other. Furthermore, the recurring cycle of epidemics-famines-rinderpest-great famines constituted a great cycle with synergy, which resulted in eco-economic-historical great catastrophes accompanied by large scale casualties. Therefore, the Gyeongsin and Eulbyeong famines occurring in the late 17th century can be treated as events caused by the repetition of various periodic disastrous factors generated in 1670~1671 and in 1695~1696 respectively, and particularly as phenomena caused by biological exchanges based on rinderpester., rather than as little ice age phenomena due to relatively long term temperature lowering.

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.

[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.

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.

Disease properties, geography, and mitigation strategies in a simulation spread of rinderpest across the United States.

For the past decade, the Food and Agriculture Organization of the United Nations has been working toward eradicating rinderpest through vaccination and intense surveillance by 2012. Because of the potential severity of a rinderpest epidemic, it is prudent to prepare for an unexpected outbreak in animal populations. There is no immunity to the disease among the livestock or wildlife in the United States (US). If rinderpest were to emerge in the US, the loss in livestock could be devastating. We predict the potential spread of rinderpest using a two-stage model for the spread of a multi-host infectious disease among agricultural animals in the US. The model incorporates large-scale interactions among US counties and the small-scale dynamics of disease spread within a county. The model epidemic was seeded in 16 locations and there was a strong dependence of the overall epidemic size on the starting location. The epidemics were classified according to overall size into small epidemics of 100 to 300 animals (failed epidemics), epidemics infecting 3,000 to 30,000 animals (medium epidemics), and the large epidemics infecting around one million beef cattle. The size of the rinderpest epidemics were directly related to the origin of the disease and whether or not the disease moved into certain key counties in high-livestock-density areas of the US. The epidemic size also depended upon response time and effectiveness of movement controls.

Characterization of the complete genomic sequence of the rinderpest virus Fusan strain cattle type, which is the most classical isolate in Asia and comparison with its lapinized strain.

In this study, we characterized the rinderpest virus (RPV) Fusan strain cattle type (B), which is the most classical isolate in Asia, by complete genomic sequence analysis and compared it with its lapinized Nakamura III (L) strain. The transversion rates of the M, F, and H genes were higher than those of other genes. In contrast, the deduced amino acid (aa) substitution rates of the P, C, and V genes were higher than those of other genes, although their transversion rates were not higher. The characteristic nucleotide (nt) or aa residues of the cattle-virulent B and Kabete 'O' strains were observed in the P/C/V, M, and L genes. According to these results, we speculate that nt/aa substitution in the P/C/V genes is one of the key determinants for the difference in the pathogenicity to cattle of the B and L strains.

Genetic characterization of the Korean LATC06 rinderpest vaccine strain.

We sequenced the genome of LATC06 generated by in vitro passage in Vero cells of the lapinized-avianized (LA) strain and compared its sequence to those of other rinderpest viruses. The LATC06 genome consists of 15882 nucleotides. Its transcriptional regulatory control sequences (TRSs) at gene boundaries are identical to those of the Kabete O strain. Cleavage sites for generating F1/F2 proteins were identified in the same amino acid position (aa 108) as F proteins in LATC06, L13, RBT1, Kabete O, and RBOK strains. There are three predicted N-glycosylation sites of H proteins in LA (Japan) and LATC06 strains. The six epitopes of H protein in the LA (Japan) strain that elicit immunodominant humoral responses are also found in the LATC06 strain.

Rinderpest virus expressing enhanced green fluorescent protein as a separate transcription unit retains pathogenicity for cattle.

A full-length DNA clone of a virulent strain of rinderpest virus was constructed with the gene for the enhanced green fluorescent protein (eGFP) inserted as a separate transcription unit between the P and M genes. Rescue of the virus from the modified clone using reverse genetics generated a virus that grew to the same levels as the virus rescued from the unmodified DNA clone in cell culture. The recombinant virus expressed eGFP to a high level and was used to follow virus replication in real-time using live-cell imaging. Cattle infected with both the recombinant wild-type virus and the recombinant eGFP expressing virus developed clinical disease similar to that of the wild-type natural virus isolate. Detection of virus in circulating peripheral blood leukocytes was equivalent to that of the animals infected with the wild-type virus. The high level of expression of soluble eGFP by this virus allowed us to detect viral replication in infected animals by confocal microscopy. Imaging vibrating microtome sections by confocal microscopy provided good preservation of tissue and cellular architecture as well as revealing the sites of replication of the virus in different tissues of infected animals.

Specific detection of Rinderpest virus by real-time reverse transcription-PCR in preclinical and clinical samples from experimentally infected cattle.

A highly sensitive detection test for Rinderpest virus (RPV), based on a real-time reverse transcription-PCR (rRT-PCR)system, was developed. Five different RPV genomic targets were examined, and one was selected and optimized to detect viral RNA in infected tissue culture fluid with a level of detection ranging from 0.59 to 87.5 50% tissue culture infectious doses (TCID(50)) per reaction depending on the viral isolate. The strain sensitivity of the test was validated on 16 RPV strains belonging to all three phylogenetic branches described for RPV. No cross-reactivity was detected with closely related peste des petit ruminants or with symptomatically similar viruses, including all seven serotypes of foot-and-mouth disease virus, two serotypes of vesicular stomatitis virus, bluetongue virus, and bovine herpes virus type 2. In samples from experimentally infected cattle, our real-time RT-PCR test was significantly more sensitive than the gold standard test of virus isolation, allowing the detection of the disease 2 to 4 days prior to the appearance of clinical signs. The comparison of clinical samples with putative diagnostic value from live animals showed that conjunctival swabs and blood buffy coat were the samples of choice for epidemiological surveillance, while lymph nodes performed the best as postmortem specimens. This portable and rapid real-time RT-PCR has the capability of the preclinical detection of RPV and provides differential diagnosis from look-alike diseases of cattle. As RPV is declared globally eradicated, this test provides an important rapid virus detection tool that does not require the use of infectious virus and allows the processing of a large number of samples.

One-step multiplex RT-PCR assay for the detection of peste des petits ruminants virus in clinical samples.

A single-tube one-step multiplex RT-PCR was standardized to amplify both 337 bp and 191 bp fragments of N and M genes of peste des petits ruminants virus (PPRV), respectively, and only a 337 bp fragment of N gene of Rinderpest virus (RPV). The RT-PCR using purified viral RNA was easily adopted for direct detection of PPRV in clinical field samples and its differentiation from RPV. The amplified N and M gene products were confirmed to be PPRV- and RPV-specific by their size in 1.5% agarose gel and restriction analysis. In the assay, the Qiagen one-step RT-PCR kit containing the Ominiscript and Sensiscript reverse transcriptases and Hot star Taq DNA polymerase was utilized. The sensitivity of the assay was found to be 100 fg of PPRV RNA. Compared with a two-step assay, the one-step assay is easier and time-saving as it requires just a single buffer for both reactions, reverse transcription (RT) and PCR. In experimentally infected goats, PPRV was detectable by the one-step RT-PCR in nasal and ocular swabs 7-17 days post infection (p.i.). and in oral swabs 7-15 days p.i. Out of 32 clinical field samples tested, 18 were positive by sandwich ELISA (S-ELISA), while 22 were positive by the one-step RT-PCR.

A model of lineage-1 and lineage-2 rinderpest virus transmission in pastoral areas of East Africa.

The development of a stochastic, state-transition model of rinderpest transmission dynamics is described using parameter estimates obtained from both laboratory and participatory research. Using serological data, the basic reproduction numbers for lineage-1 rinderpest virus in southern Sudan and for lineage-2 rinderpest virus in Somali livestock were estimated as 4.4 and between 1.2 and 1.9, respectively. The model predictions for the inter-epidemic period in Sudan and Somalia (1.2 and 4.2 years, respectively) were in agreement with analysis of livestock-owner reports (1-2 years and 5 years, respectively).

A rapid chromatographic strip test for the pen-side diagnosis of rinderpest virus.

Rinderpest is a contagious viral disease of cloven-hoofed domestic and wild animals. Eradication of the virus following outbreaks depends on rapid and accurate diagnosis of infection and the implementation of control measures. Reporting and confirmatory diagnosis precede the implementation of control measures. A number of techniques have been used for diagnosis such as agar gel immunodiffusion, enzyme-linked immunosorbent assay (ELISA), molecular biological techniques such as polymerase chain reaction (PCR) and virus isolation in tissue culture. Many of these methods are both time consuming and require skilled personnel. The development of a rapid pen-side test for the detection of rinderpest virus (RPV) antigen in lachrymal fluid of cattle is described using the Clearview chromatographic strip test technology (Unipath, Bedford). Optimum conditions for binding monoclonal antibody to nitrocellulose and latex microspheres were determined and a prototype device was developed. The device detected viral antigen in lachrymal fluids from experimentally and naturally infected cattle and showed no cross-reactivity with other related viruses. A field trial was carried out at the Landhi Cattle Colony (LCC), Pakistan, to assess the performance of the rinderpest test under field conditions. Ninety-seven animals, some of which were showing various clinical signs, at LCC and neighbouring colonies were sampled and tested at the pen-side by Clearview and later by immunocapture ELISA (IC-ELISA) at IAH, Pirbright. Nineteen animals were positive by Clearview and/or IC-ELISA. Seventeen out of 19 rinderpest positive animals were positive by Clearview and 15 out of 19 were positive by IC-ELISA. Reverse transcription polymerase chain reaction (RT-PCR) confirmed the 19 animals to be rinderpest positive. This simple, rapid, specific test allows for the first time, accurate pen-side diagnosis of rinderpest.

Characterisation of African isolates of rinderpest virus.

Isolates of rinderpest virus (RPV) recovered from outbreaks of the disease in Kenya and Southern Sudan between 1986 and 1993 were compared to each other and to earlier isolates from East and West Africa. The recent isolates were mildly pathogenic for susceptible cattle and thus resembled other mild strains of RPV recovered from cattle and wildlife in East Africa more than 30 years ago. Monoclonal antibody analysis using a panel of 12 anti-RPV haemagglutinin protein-specific antibodies (mAbs) revealed that individual isolates were distinguishable. However, the panel of mAbs could not be used to relate the isolates on the basis of their pathogenicity or geographic origin. Immunoprecipitation of the virus-induced proteins from infected Vero cells, followed by SDS-polyacrylamide gel electrophoresis, showed that the recent mild RPV isolates from eastern Africa were closely related to each other and to their contemporary isolates from Nigeria and Egypt, but they were distinct from another mild isolate recovered from the region three decades ago. Two distinct lineages of African RPV isolates were identified by sequencing a region of the genome around the proteolytic enzyme cleavage site of the fusion protein from the old and new isolates. One lineage, which included virus isolates recovered from East and West Africa during the 1960s, showed a closer phylogenetic relationship to Asian and Middle Eastern RPV isolates. The other lineage consisted mainly of isolates recovered from East, West and North Africa between 1983 and 1993. The results showed that there was co-circulation of two different lineages of RPV in Nigeria during the epizootics of the 1980s.

Immunizing effect of vaccinia virus expressing the nucleoprotein of rinderpest virus on systemic rinderpest virus infection in rabbits.

A recombinant vaccinia virus (RVV) expressing the nucleoprotein (NP) of rinderpest virus (RPV) was examined in rabbits for the involvement of the NP protein in protection from the RPV infection. Despite their production of anti-NP antibody, the RVV-immunized rabbits succumbed to the RPV challenge, although there was a slight delay in the onset of disease after the low-dose challenge. On the other hand, the animals immunized with RVV expressing the hemagglutinin (H) protein of the RPV were completely protected. These results indicate that the NP protein might be not so effective as the H protein for the protection against viremic and systemic infection with RPV.

Induction of apoptotic cellular death in lymphatic tissues of cattle experimentally infected with different strains of rinderpest virus.

The presence, type, and extent of cellular death in lymphatic tissues of cattle experimentally infected with rinderpest virus strains of different virulence was investigated morphologically. Cells with DNA strand breaks were identified in histological sections of palatine tonsil, spleen, and mesenteric and mandibular lymph nodes by the TUNEL (terminal desoxynucleotidyl transferase-mediated dUTP nick end labelling) assay. In addition, representative samples of lymphatic tissues were examined by transmission electron microscopy. The results indicated that cellular disassembly in lymphatic tissues was caused by both apoptosis and oncosis. Cells with DNA strand breaks were observed in follicular and parafollicular areas of lymphatic tissues and their numbers were determined. A significant correlation was found between the number of TUNEL-positive cells and viral virulence. These results suggest that, in addition to oncosis, apoptotic cellular death in lymphatic tissues contributes substantially to the pathogenesis of rinderpest.