A Mouse Model of PPRV Infection for Elucidating Protective and Pathological Roles of Immune Cells.

The study was aimed at developing an accessible laboratory animal model to elucidate protective and pathological roles of immune mediators during Peste des petits ruminants virus (PPRV) infection. It is because of the critical roles of type I IFNs in anti-viral defense, we assessed the susceptibility of IFN receptor knock out (IFNR KO) mice to PPRV infection. IFNR KO mice were exceedingly susceptible to the infection but WT animals efficiently controlled PPRV. Accordingly, the PPRV infected IFNR KO mice gradually reduced their body weights and succumbed to the infection within 10 days irrespective of the dose and route of infection. The lower infecting doses predominantly induced immunopathological lesions. The viral antigens as well as the replicating PPRV were abundantly present in most of the critical organs such as brain, lungs, heart and kidneys of IFNR KO mice infected with high dose of the virus. Neutrophils and macrophages transported the replicating virus to central nervous system (CNS) and contributed to pathology while the elevated NK and T cell responses directly correlated with the resolution of PPRV infection in WT animals. Using an array of fluorescently labeled H-2Kb tetramers, we discovered four immunogenic epitopes of PPRV. The PPRV-peptides interacted well with H-2Kb in acellular and cellular assay as well as expanded the virus-specific CD8+ T cells in immunized or infected mice. Adoptively transferred CD8+ T cells helped control PPRV in infected mice. Our study therefore established and employed a mouse model for investigating the pathogenesis of PPRV. The model could be useful for elucidating the contribution of immune cells in disease progression as well as to test anti-viral agents.

Evaluation of effectiveness of Mass Vaccination Campaign against Peste des petits ruminants in Chhattisgarh state, India.

The study evaluated the effectiveness of 'Mass Vaccination Campaign (MVC)' implemented against the contagious transboundary OIE notified Peste des petits ruminants (PPR) in sheep and goats on the lines of 'pulse polio campaign' for humans in Chhattisgarh state, India. The effectiveness was evaluated on the axes of adequacy, financial viability under with and without MVC through differencing under various scenarios and options and programme impact from a farmer's perspective. The adequacy evaluation revealed that the reported outbreaks, diagnosed and death cases declined under PPR-MVC inconsonance with increased vaccination coverage. Furthermore, the seroconversion increased during post PPR-MVC implies elevated immunity levels in the sheep and goat population. The estimated mean mortality loss was USD 45.2 and USD 16.5 per animal in goats and sheep, respectively, whereas the treatment and opportunity cost of labour was USD 1.9 and USD 2.5 per animal respectively. Under the low PPR incidence scenario, benefit: cost ratio, net present value and internal rate of return were 4.9:1, 48.9 million USD and 146.6%, whereas it was 12.4:1,142.7 million USD and 430.4% and 13.5:1,156.7 million USD and 430.4% under medium and high incidence scenarios. Furthermore, the option of vaccinating 100% risk population during the first year followed by 30% during subsequent years to cover naïve population will maximize benefits than 100% coverage every year; nevertheless, benefits outweighs cost manifolds in both of these options. The farmers had a positive opinion on the overall services provided under PPR-MVC and the results provide the empirical evidence on effectiveness of 'mass vaccination' for its replication in other states of India or countries with similar socio-economic and rearing environments.

Fatal peste des petits ruminants disease in Chowsingha.

This communication reports fatal Peste des petits ruminants (PPR) disease in Chowsingha (Tetracerus quadricornis), a member of the subfamily Bovinae and family Bovidae captured in a Zoological Park. The animals showed clinical signs of acute respiratory disease with frothy nasal discharge (1-2 days) and mortality of twenty animals (80%) within 48 hr. Necropsy of dead Chowsingha showed haemorrhagic patches in trachea and severe congestion of lungs and ocular mucosa. There was no characteristic lesion in the intestine. Swabs from trachea and nasal tract along with tissue samples of spleen and lung from dead animals were found positive for PPR virus based on reverse transcription-polymerase chain reaction using H gene and partial N gene-specific primers. Sequence analysis of complete H gene and partial N gene confirmed the aetiological agent as PPR virus lineage IV. The identity of the Chowsingha tissues used for PPRV isolation was confirmed by the 12S ribosomal RNA gene sequencing, and the amplified gene was analysed identically to the Chowsingha mitochondrial 12S ribosomal RNA gene. The present information of PPR in Chowsingha is the first report of PPRV lineage IV causing cross-species fatal disease in subfamily bovinae and family Bovidae. The acute manifestation of the disease indicates high susceptibility of this vulnerable wild bovid species to PPR lineage IV. This report extends host range and demands enhanced surveillance among subfamily bovinae to strengthen PPR eradication programme.

The economic impact of peste des petits ruminants in India.

Peste des petits ruminants (PPR) is an economically important livestock disease which affects a vast section of the small ruminant population in India. However, data on the incidence of PPR are limited and scant literature is available on the economic losses caused by the disease. In the present study, a structured sampling design was adopted, which covered the major agro-climatic regions of the country, to ascertain the morbidity and mortality rates of PPR. Available estimates of the economic losses in India due to various livestock diseases are based on single values of various epidemiological and economic parameters. Stochastic modelling was used to estimate the economic impact of PPR. Overall annual morbidity and mortality rates of PPR for small ruminants in India have been estimated from the sample as being 8%and 3.45%, respectively. The authors have analysed variations in these rates across species, age group, sex, season and region. The expected annual economic loss due to PPR in India ranges from as little as US $2 million to $18 million and may go up to US $1.5 billion; the most likely range of expected economic losses is between US $653 million and $669 million. This study thus reveals significant losses due to the incidence of PPR in small ruminants in India.

La peste des petits ruminants (PPR) est une maladie du bétail à fort impact économique. En Inde, une grande partie de la population des petits ruminants est affectée. Cependant, les données disponibles sur l'incidence de la PPR sont rares et très peu d'articles ont été consacrés aux pertes économiques causées par la maladie. Les auteurs présentent une étude basée sur un échantillonnage structuré couvrant les principales régions agro-climatiques du pays, visant à déterminer avec certitude les taux de morbidité et de mortalité de la PPR. Les estimations disponibles des pertes économiques induites par diverses maladies des animaux d'élevage sont basées sur des valeurs uniques correspondant à divers paramètres épidémiologiques et économiques. Les auteurs ont évalué l'impact économique de la PPR en utilisant un modèle stochastique. En se basant sur l'échantillon, les taux annuels de morbidité et de mortalité de la PPR chez les petits ruminants en Inde ont été respectivement estimés à 8 % et à 3,45 %. Les auteurs ont également analysé les variations de ces taux en fonction de l'espèce, du groupe d'âge, du sexe, de la saison et de la région. Les pertes annuelles attendues imputables à la PPR en Inde fluctuent d'un minimum de 2 millions de dollars US (USD) à 18 millions d'USD, mais elles peuvent atteindre 1,5 milliard d'USD ; la fourchette la plus probable des pertes économiques attendues se situe entre 653 millions et 669 millions d'USD. Cette étude souligne l'importance des pertes économiques liées à la présence de la PPR en Inde.

La peste de pequeños rumiantes (PPR) es una enfermedad del ganado que reviste importancia económica y afecta a un vasto segmento de la población de pequeños rumiantes de la India. Sin embargo, existen pocos datos sobre su incidencia y muy escasas referencias bibliográficas sobre las pérdidas económicas que ocasiona. Los autores describen un estudio encaminado a determinar las tasas de morbilidad y mortalidad por PPR a partir de un muestreo estructurado que abarcaba las principales regiones agroclimáticas del país. Las estimaciones existentes de las pérdidas económicas causadas en la India por diversas enfermedades del ganado están basadas en valores únicos de diversos parámetros epidemiológicos y económicos. Para estimar el impacto económico de la PPR se utilizó una modelización estocástica. A partir de la muestra se calculó que, en los pequeños rumiantes del país, los índices anuales de morbilidad y mortalidad totales por PPR se cifran en un 8% y un 3,45%, respectivamente. Los autores analizaron después las variaciones que exhiben esos índices por especie, grupo de edad, sexo, estación y región. La cuantía prevista de las pérdidas económicas anuales causadas por la PPR en el país oscila: de apenas 2 a 18 millones de dólares estadounidenses puede llegar hasta los 1 500 millones. El intervalo más probable de pérdidas económicas se sitúa entre 653 y 669 millones. El estudio demuestra pues que la incidencia de la PPR entre los pequeños rumiantes de la India provoca pérdidas de importante magnitud.

Genome characterization and phylogenetic analysis of a lineage IV peste des petits ruminants virus in southern China.

Since 2013, the second outbreak of peste des petits ruminants (PPR) caused by Peste des petits ruminants virus (PPRV) has spread over more than 20 provinces, municipalities, and autonomous regions in China, resulting in major economic losses for livestock industry. In 2014, we encountered a clinical PPR case on a goat farm in Guangdong province, southern China. The complete genome of this PPRV strain, named CH/GDDG/2014, was sequenced to determine its similarities and differences with other strains. The CH/GDDG/2014 genome comprised 15,954 nucleotides (six nucleotides more than classical PPRVs identified before 2013, but complying with the rule of six) with six open reading frames encoding nucleocapsid protein, phosphoprotein, matrix protein, fusion protein, hemagglutinin, and large polymerase protein, respectively. The whole-genome-based alignment analysis indicated that CH/GDDG/2014 had the most proximate consensus (99.8 %) to China/XJYL/2013 and the least consensus (87.2 %) to KN5/2011. The phylogenetic analysis showed that CH/GDDG/2014 was clustered in one branch (lineage IV) with other emerging strains during the second outbreak. This study is the first report describing the whole-genome sequence of PPRV in Guangdong province, southern China and also suggests the PPR outbreak may be closely related to illegal cross-regional importation of goats.

Peste des petits ruminants outbreaks in White Nile State, Sudan.

Eight outbreaks of peste des petits ruminants in sheep and goats were reported in White Nile State, Sudan, between 2008 and 2009. A mortality rate of 4.2% was reported across the different outbreaks. Clinically the disease was characterised by high fever, ocular and nasal discharge, pneumonia, ulceration of the mucous membranes, diarrhoea and death. The postmortem findings included necrotic lesions in the mouth and gastrointestinal tract, and swollen, oedematous lymph nodes associated with the lungs and intestine. Of the 209 serum samples tested by competitive enzyme-linked immunosorbent assay, 113 (54%) were found positive. Peste des petits ruminants virus was confirmed in tissues, nasal swabs and blood samples by immunocapture enzyme-linked immunosorbent assay, reverse-transcription polymerase chain reaction and isolation of the virus in culture of lamb testicle cells.

Natural peste des petits ruminants virus infection in Black Bengal goats: virological, pathological and immunohistochemical investigation.

BACKGROUND: Peste des Petits Ruminants (PPR), also known as Goat Plague, occurs in goats, sheep and related species. It is caused by a morbillivirus in the family Paramyxoviridae. In Bangladesh PPR is endemic and it causes serious economic losses. Pathology of PPR has been reported in different goat and sheep breeds from natural and experimental infections. Field results are better indicators of pathogenicity of the circulating virus. The severity of the disease varies with species, breed and immune status of the host. Pathological investigations of natural outbreaks of PPR in Balck Bengal goats are very limited. The current investigation was aimed at describing pathology and antigen localization in natural PPR infections in Black Bengal goats. RESULTS: A total of 28 outbreaks were investigated clinically and virologically. Average flock morbidity and mortality were 75% and 59%, respectively, with case fatality rate of 74%. Necropsy was conducted on 21 goats from 15 outbreaks. The major gross lesions were congestion of gastrointestinal tract, pneumonia, engorged spleen, and oedematous lymphnodes. Histopathological examination revealed severe enteritis with denudation of intestinal epithelium, severe broncho-interstitial pneumonia with macrophages within lung alveoli and extensive haemorrhages with depletion of lymphoid cells and infiltration of macrophages in the sinuses of spleen. In lymph nodes, the cortical nodules were replaced by wide sinusoids with severe depletion of lymphocytes, infiltration of mononuclear cells and some giant cells in sub-capsular areas and medullary sinuses. PPR virus antigen was found in pneumocytes and alveolar macrophages in lungs. Viral RNA could be detected by RT-PCR in 69 out of 84 nasal swab, 59 out of 84 blood and 21 out of 21 lymph node samples. Sequence analyses revealed closeness of Bangladeshi strains with other recent Asian isolates. CONCLUSION: Natural outbreaks of PPR in Black Bengal goats in Bangladesh resulted in 75% and 59% flock morbidity and mortality, respectively, with a case fatality rate of 74%. The striking histo-morphologic diagnosis of PPR was acute pneumonia and severe gastro-enteritis. A detailed experimental pathological study on Black Bengal goats infected with recent isolates is required.

Emergence of peste des petits ruminants virus lineage IV in Ismailia Province, Egypt.

Peste des petits ruminants (PPR) is an acute, highly contagious fatal disease of small ruminants characterized by high fever, ocular and nasal discharge, pneumonia, erosive stomatitis and severe enteritis that ultimately results in high mortalities. Peste des petits ruminants virus (PPRV) is widely distributed and endemic in several African, middle eastern and south Asian countries and it poses a threat to European countries. Egyptian veterinary medical authorities stated that Egypt is free from PPRV and the only measures for disease control are test and slaughter of infected population to maintain the free status. The aim of our investigation was to detect PPRV in Ismailia province as an indicator of the infection status in Egypt and perform molecular characterization of the emerging virus to gain insight into the origin of circulating virus. A total of 40 representative clinical samples, from a single goat case and goat flock in 2010 and sheep flock in 2012, were tested for PPRV by RT-PCR. About 21 (52.5%) samples were positive. The phylogenetic analysis of the detected viruses revealed circulation of PPRV lineage IV. The circulating viruses are closely related to Sudanese and Saudia Arabian strains with nucleotide identity ranged from 99.2% to 99.6%, respectively. Also, it is closely related to Moroccan 2008 viruses with identities ranged from 97.6% to 98%. Epidemiological investigation at the national level is recommended for monitoring PPRV spread and implementing an appropriate control program.

Fatalities in wild goats in Kurdistan associated with Peste des Petits Ruminants virus.

Between August 2010 and February 2011, over 750 deaths were recorded among wild goats (Capra aegagrus, the endangered progenitor of the domestic goat) in Kurdistan. Based on the clinical signs and post-mortem findings, the involvement of peste des petits ruminants virus (PPRV) was suspected. This was confirmed by laboratory analysis, and the virus was found to be closely related to a Turkish strain isolated in 2000. During the outbreak in wild goats, no disease in domestic animals was reported. Domestic ruminants in the region are routinely vaccinated with an attenuated vaccine based on the 'Nigeria/75/1' strain of PPRV. This is the first report of active PPRV infection in Kurdistan and most likely the immunity afforded by vaccination prevented spillover infections. It is therefore recommended to continue with the campaign. Conversely, there is no justification for the use of force to keep the endangered wild goats away from domestic flocks.

Occurrence of dual infection of peste-des-petits-ruminants and goatpox in indigenous goats of central India.

Peste-des-petits-ruminants (PPR), bluetongue (BT) and goatpox (GP) have been well recognized as causes of significant economic losses in the small ruminant population of Asia and Africa. We describe here the occurrence of these three in an outbreak noticed in non-descript goats from a subtropical region of central India. An investigation was carried out to confirm the aetiology of the heavy mortality in goats (74.6%, 112/150), with testing of samples from 12 surviving animals exhibiting mixed clinical signs indicative of PPR, BT and GP. Sandwich ELISA was used to detect PPR virus antigen and competition ELISA to detect PPR virus and BT virus antibodies. GP was confirmed on the basis of nodular lesions and an immunodiffusion assay. Eight of the 12 affected animals (66.7%) were positive for PPR virus and BT virus antibodies, and two goats (16.7%, 2/12) exhibiting clinical lesions of pox were also found positive for PPR virus/antibodies and BT virus antibodies, respectively. Although BT virus could not be identified in any sample, detection of BT virus antibodies indicated previous or possibly concurrent infection with BT virus in these goats. The N-gene-based RT-PCR was used to confirm the PPR infection in these goats, and one of the amplicons was sequenced. The sequence and phylogenetic analysis revealed close proximity to PPR virus isolates from Tibet and China, with sequence homology of up to 96.9%. The sequence homology was relatively low with the majority of other Indian isolates (72.7-93.5%). The detection of this new PPR virus sequence indicates the circulation of cross-border strains in this region of India. It is presumed that the heavy mortality observed in goats is possibly attributable to the occurrence of mixed infection of PPR and GP, or PPR, BT and GP.

Peste des petitis ruminants morbillivirus infection in lambs and young goats at Qassim region, Saudi Arabia.

An outbreak of peste des petits ruminants (PPR) in lambs and young goats of Najdi breed of sheep and goats occurred during winter 2005 at Qassim region of central Saudi Arabia. The PPR infection was confirmed by demonstration of antibodies against the virus in the serum of clinically-ill young sheep and goats using competitive ELISA test. Clinical examination of infected animals showed fever, salivation, lacrimation, mucopurulent nasal discharge, difficult breathing and diarrhoea. The disease was particularly severe in the goats. Morbidity was about 20% and mortality was less than 3 percent. Autopsy showed necrotic and ulcerative lesions in the mouth, stomach and intestine. Mesenteric lymph nodes were swollen and congested. The lungs were patchy pneumonic mostly at the diaphragmatic and apical lobes. Liver and kidney lesions were seen in goats only and both organs were congested and necrotic. Histopathological examination revealed necrotic inflammation in the gastrointestinal tract. Intracytoplasmic viral inclusions were seen in the enterocytes of goats. Lung sections showed bronchopneumonia and syncytial and giant cells. The bronchial epithelium of goats had intracytoplasmic viral inclusions. Extensive coagulation necrosis, fatty degeneration and presence of intracytoplasmic viral inclusions were seen in hepatocytes and syncytial cells were evident in biliary epithelium of goats. Congestion, coagulation necrosis and syncytial cells were seen in the renal tubular epithelium of goats only. In a survey to determine the magnitude of the outbreak, PPR antibodies were evidenced in 363/996 (36.6%) sheep and 530/962 (55.1%) goats.

Prevalence and mortality rate of peste des petitis ruminant (PPR): possible association with abortion in goat.

Present study was designed to investigate the prevalence and mortality (%) caused by Peste des Petitis Ruminant (PPR) and its possible association with abortion in goat flocks at different areas of Pakistan. A total of 140 animals were samples in the population of 650 which was having 185 deaths (Mortality rate = 28 %) from three different regions of the country. There were 58 abortions in the 140 pregnant goats of above said population One hundred & ten (110) serum samples from diseased, recovered and apparently healthy animals were tested for the presence of PPR antibodies by competitive ELISA (c ELISA). Eighty-four (84) animals were positive for PPR antibodies whereas in apparently healthy adult goats in the same flock, no PPR antibodies were detected. Twenty-four (24) tissue samples collected from the dead animals and six samples from aborted fetus were tested for the presence of PPR antigen by Immuno-capture ELISA (Ic ELISA). Nineteen (19) out of thirty (30) organ samples mainly from lung, spleen, lymph node were found positive for PPR antigen but negative from lungs of aborted fetus. There was a high rate of abortions (28-45%) in each of the outbreak and it was highest in the outbreak of Golra Sharif, Islamabad (No. = 21 in total population of 100). As the serum samples from the aborted dams were found positive for PPR antibodies so the study provides the possible association of mortality and prevalence of PPR disease with high rate of abortions in goat.

Control of peste des petits ruminants: classical and new generation vaccines.

Peste des Petits Ruminants is a highly contagious disease of domestic and wild small ruminants. It seems to be the major constraint in the development of small ruminant production in areas where it is endemic. Included in the list A of the International Zoosanitary Code, it is also part of the FAO EMPRESS programme. Classically, it is characterised by fever, nasal and ocular discharges, diarrhoea, respiratory distress, mucosal erosive lesions and death in 40-80% of acute cases. All these clinical signs, apart from the respiratory symptoms, are very similar to those of rinderpest. The causal agents of both diseases are closely related and belong to the Morbillivirus genus. In the absence of homologous vaccine, and taking advantage of the close relationship between the two viruses, the attenuated tissue culture rinderpest vaccine has been used for a long time to protect small ruminants against PPR. At the end of 1980s, a PPRV strain was successfully attenuated by serial passages in Vero cells. Demonstrated to be very efficient in the protection of sheep and goats against a virulent challenge, this avirulent PPRV is now widely used in the control of PPR. Its thermostability has been dramatically improved by freeze drying. However, animals inoculated with this vaccine cannot be distinguished serologically from those infected with the wild type viruses. With the reverse genetics technique, it is now possible to engineer PPR marker vaccines which can allow such a differentiation. The genes of the PPRV immune protective proteins, the fusion and the haemagglutinin proteins, have been introduced into the genome of a capripox vaccine strain. The generated viruses have proved to be effective as a dual vaccine to protect against two major diseases of small ruminants: peste des petits ruminants and capripox infections.