First genetic characterization of peste des petits ruminants virus from Mongolia

Assessment of Peste des Petits Ruminants Antibodies in Vaccinated Pregnant Ewes of Kazakh Breed Fine-Fleeced and Determination of the Decreasing Trend of Maternal Immunity in Their Lambs

In this article, we first assessed peste des petits ruminants (PPR) antibodies in vaccinated pregnant ewes of Kazakh breed fine-fleeced immunized with the PPR vaccine and the duration of maternal immunity in their lambs. Ewes in the last trimester of pregnancy and gestation were immunized with a vaccine from the Nigeria 75/1 strain of the PPR virus (PPRV) produced by the Research Institute of Biological Safety Problems (RIBSP), Kazakhstan. Serum samples from lambs born from vaccinated and unvaccinated ewes were collected a week after birth and at intervals of 7 days for 18 weeks after birth. Serum samples collected from lambs were tested for PPR antibodies using competitive ELISA and virus neutralization test (VNT). Maternal antibodies (MAs) in lambs born from vaccinated ewes were detected for up to 18 weeks, with a tendency to decrease starting at week 14, and by the end of the experiment receded below the protective level (<1:8). In the blood serum of a 14-week-old lamb with MAs (1:8), post vaccination with a field dose (103 TCID50) of the vaccine against PPR, the titers of protective antibodies against PPRV increased to 1:16 on day 14 post vaccination, and the lamb was protected from infection with the field PPRV. A lamb of the same age with MAs in the 1:8 titer was 100% protected from infection with the field PPRV. Therefore, it is recommended that lambs of the Kazakh fine-wool breed be immunized from the age of 14 weeks or older to avoid a period of susceptibility.

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.

Peste des Petits Ruminants in Central and Eastern Asia/West Eurasia: Epidemiological Situation and Status of Control and Eradication Activities after the First Phase of the PPR Global Eradication Programme (2017–2021)

Simple Summary

Peste des petits ruminants (PPR) is a highly contagious viral disease of domestic and wild small ruminants. The disease is endemic to large parts of Africa, the Middle East and Asia and causes severe socioeconomic losses, especially in developing countries reliant on small ruminant value chains. Currently, PPR is the only animal disease targeted by the Global Eradication Programme (PPR GEP), which aims to eradicate the disease by 2030. Following the end of the first five-year phase of the PPR GEP, the goal of this review is to provide an update on the status of the eradication progress in one of the nine regions targeted for coordinated action in the PPR Global Control and Eradication Strategy, denominated Central Asia/West Eurasia. In addition to the original nine countries, regional meetings and activities have involved four additional countries based on shared epidemiological features, which are also reviewed here. The considered area spans from Eastern Europe to East Asia and features remarkable variability in terms of both PPR presence and enacted control efforts. The achievements and constraints encountered at regional and national levels are discussed, thus providing useful data for tailoring the next steps of the eradication programme to the peculiarities of the region.

Abstract

Peste des petits ruminants (PPR) is a highly contagious infectious disease of small ruminants caused by peste des petits ruminants virus (PPRV). PPR poses a significant threat to sheep and goat systems in over 65 endemic countries across Africa, the Middle East and Asia. It is also responsible for devastating outbreaks in susceptible wildlife, threatening biodiversity. For these reasons, PPR is the target of the Global Eradication Programme (PPR GEP), launched in 2016, which is aimed at eradicating the disease by 2030. The end of the first five-year phase of the PPR GEP (2017–2021) provides an ideal opportunity to assess the status of the stepwise control and eradication process. This review analyses 13 countries belonging to Eastern Europe, Transcaucasia, and Central and East Asia. Substantial heterogeneity is apparent in terms of PPR presence and control strategies implemented by different countries. Within this region, one country is officially recognised as PPR-free, seven countries have never reported PPR, and two have had no outbreaks in the last five years. Therefore, there is real potential for countries in this region to move forward in a coordinated manner to secure official PPR freedom status and thus reap the trade and socioeconomic benefits of PPR eradication.

Molecular epidemiology of peste des petits ruminants virus emergence in critically endangered Mongolian saiga antelope and other wild ungulates

Peste des petits ruminants virus (PPRV) causes disease in domestic and wild ungulates, is the target of a Global Eradication Programme, and threatens biodiversity. Understanding the epidemiology and evolution of PPRV in wildlife is important but hampered by the paucity of wildlife-origin PPRV genomes. In this study, full PPRV genomes were generated from three Mongolian saiga antelope, one Siberian ibex, and one goitered gazelle from the 2016-2017 PPRV outbreak. Phylogenetic analysis showed that for Mongolian and Chinese PPRV since 2013, the wildlife and livestock-origin genomes were closely related and interspersed. There was strong phylogenetic support for a monophyletic group of PPRV from Mongolian wildlife and livestock, belonging to a clade of lineage IV PPRV from livestock and wildlife from China since 2013. Discrete diffusion analysis found strong support for PPRV spread into Mongolia from China, and phylogeographic analysis indicated Xinjiang Province as the most likely origin, although genomic surveillance for PPRV is poor and lack of sampling from other regions could bias this result. Times of most recent common ancestor (TMRCA) were June 2015 (95 per cent highest posterior density (HPD): August 2014 to March 2016) for all Mongolian PPRV genomes and May 2016 (95 per cent HPD: October 2015 to October 2016) for Mongolian wildlife-origin PPRV. This suggests that PPRV was circulating undetected in Mongolia for at least 6 months before the first reported outbreak in August 2016 and that wildlife were likely infected before livestock vaccination began in October 2016. Finally, genetic variation and positively selected sites were identified that might be related to PPRV emergence in Mongolian wildlife. This study is the first to sequence multiple PPRV genomes from a wildlife outbreak, across several host species. Additional full PPRV genomes and associated metadata from the livestock-wildlife interface are needed to enhance the power of molecular epidemiology, support PPRV eradication, and safeguard the health of the whole ungulate community.

Complete Genome Sequencing of Field Isolates of Peste des Petits Ruminants Virus from Tanzania Revealed a High Nucleotide Identity with Lineage III PPR Viruses

Peste des petits ruminants virus (PPRV) causes a highly devastating disease of sheep and goats that threatens food security, small ruminant production and susceptible endangered wild ruminants. With policy directed towards achieving global PPR eradication, the establishment of cost-effective genomic surveillance tools is critical where PPR is endemic. Genomic data can provide sufficient in-depth information to identify the pockets of endemicity responsible for PPRV persistence and viral evolution, and direct an appropriate vaccination response. Yet, access to the required sequencing technology is low in resource-limited settings and is compounded by the difficulty of transporting clinical samples from wildlife across international borders due to the Convention on International Trade in Endangered Species (CITES) of Wild Fauna and Flora, and Nagoya Protocol regulations. Oxford nanopore MinION sequencing technology has recently demonstrated an extraordinary performance in the sequencing of PPRV due to its rapidity, utility in endemic countries and comparatively low cost per sample when compared to other whole-genome (WGS) sequencing platforms. In the present study, Oxford nanopore MinION sequencing was utilised to generate complete genomes of PPRV isolates collected from infected goats in Ngorongoro and Momba districts in the northern and southern highlands of Tanzania during 2016 and 2018, respectively. The tiling multiplex polymerase chain reaction (PCR) was carried out with twenty-five pairs of long-read primers. The resulting PCR amplicons were used for nanopore library preparation and sequencing. The analysis of output data was complete genomes of PPRV, produced within four hours of sequencing (accession numbers: MW960272 and MZ322753). Phylogenetic analysis of the complete genomes revealed a high nucleotide identity, between 96.19 and 99.24% with lineage III PPRV currently circulating in East Africa, indicating a common origin. The Oxford nanopore MinION sequencer can be deployed to overcome diagnostic and surveillance challenges in the PPR Global Control and Eradication program. However, the coverage depth was uneven across the genome and amplicon dropout was observed mainly in the GC-rich region between the matrix (M) and fusion (F) genes of PPRV. Thus, larger field studies are needed to allow the collection of sufficient data to assess the robustness of nanopore sequencing technology.

Characterisation of Peste Des Petits Ruminants Disease in Pastoralist Flocks in Ngorongoro District of Northern Tanzania and Bluetongue Virus Co-Infection

Peste des petits ruminants (PPR) disease was first confirmed in Tanzania in 2008 in sheep and goats in Ngorongoro District, northern Tanzania, and is now endemic in this area. This study aimed to characterise PPR disease in pastoralist small ruminant flocks in Ngorongoro District. During June 2015, 33 PPR-like disease reports were investigated in different parts of the district, using semi-structured interviews, clinical examinations, PPR virus rapid detection test (PPRV-RDT), and laboratory analysis. Ten flocks were confirmed as PPRV infected by PPRV-RDT and/or real-time reverse transcription-polymerase chain reaction (RT-qPCR), and two flocks were co-infected with bluetongue virus (BTV), confirmed by RT-qPCR. Phylogenetic analysis of six partial N gene sequences showed that the PPR viruses clustered with recent lineage III Tanzanian viruses, and grouped with Ugandan, Kenyan and Democratic Republic of Congo isolates. No PPR-like disease was reported in wildlife. There was considerable variation in clinical syndromes between flocks: some showed a full range of PPR signs, while others were predominantly respiratory, diarrhoea, or oro-nasal syndromes, which were associated with different local disease names (olodua-a term for rinderpest, olkipiei-lung disease, oloirobi-fever, enkorotik-diarrhoea). BTV co-infection was associated with severe oro-nasal lesions. This clinical variability makes the field diagnosis of PPR challenging, highlighting the importance of access to pen-side antigen tests and multiplex assays to support improved surveillance and targeting of control activities for PPR eradication.

A comprehensive global perspective on phylogenomics and evolutionary dynamics of Small ruminant morbillivirus

A string of complete genome sequences of Small ruminant morbillivirus (SRMV) have been reported from different parts of the globe including Asia, Africa and the Middle East. Despite individual genome sequence-based analysis, there is a paucity of comparative genomic and evolutionary analysis to provide overarching and comprehensive evolutionary insights. Therefore, we first enriched the existing database of complete genome sequences of SRMVs with Pakistan-originated strains and then explored overall nucleotide diversity, genomic and residue characteristics, and deduced an evolutionary relationship among strains representing a diverse geographical region worldwide. The average number of pairwise nucleotide differences among the whole genomes was found to be 788.690 with a diversity in nucleotide sequences (0.04889 ± S.D. 0.00468) and haplotype variance (0.00001). The RNA-dependent-RNA polymerase (L) gene revealed phylogenetic relationship among SRMVs in a pattern similar to those of complete genome and the nucleoprotein (N) gene. Therefore, we propose another useful molecular marker that may be employed for future epidemiological investigations. Based on evolutionary analysis, the mean evolution rate for the complete genome, N, P, M, F, H and L genes of SRMV was estimated to be 9.953 × 10^–4, 1.1 × 10^–3, 1.23 × 10^–3, 2.56 × 10^–3, 2.01 × 10^–3, 1.47 × 10^–3 and 9.75 × 10^–4 substitutions per site per year, respectively. A recombinant event was observed in a Pakistan-originated strain (KY967608) revealing Indian strains as major (98.1%, KR140086) and minor parents (99.8%, KT860064). Taken together, outcomes of the study augment our knowledge and current understanding towards ongoing phylogenomic and evolutionary dynamics for better comprehensions of SRMVs and effective disease control interventions.

Outbreak of Peste des Petits Ruminants among Critically Endangered Mongolian Saiga and Other Wild Ungulates, Mongolia, 2016-2017

The 2016-2017 introduction of peste des petits ruminants virus (PPRV) into livestock in Mongolia was followed by mass mortality of the critically endangered Mongolian saiga antelope and other rare wild ungulates. To assess the nature and population effects of this outbreak among wild ungulates, we collected clinical, histopathologic, epidemiologic, and ecological evidence. Molecular characterization confirmed that the causative agent was PPRV lineage IV. The spatiotemporal patterns of cases among wildlife were similar to those among livestock affected by the PPRV outbreak, suggesting spillover of virus from livestock at multiple locations and time points and subsequent spread among wild ungulates. Estimates of saiga abundance suggested a population decline of 80%, raising substantial concerns for the species' survival. Consideration of the entire ungulate community (wild and domestic) is essential for elucidating the epidemiology of PPRV in Mongolia, addressing the threats to wild ungulate conservation, and achieving global PPRV eradication.

Hard ticks and tick-borne pathogens in Mongolia-A review

Ticks and tick-borne pathogens (TBPs) pose a considerable threat to human and animal health in Mongolia; a large and sparsely inhabited country whose economy is largely dependent on animal production. Intensive contact between herdsmen and their livestock, together with the use of pastures without fencing, allows contact between wildlife, domestic animals and humans, thus creating ideal conditions for epizoonoses and zoonoses. Consequently, ticks and TBPs cause significant medical, veterinary, and economical concern. This review summarizes the current state of knowledge about this zoonotic problem in Mongolia, focusing on tick species from the genera Ixodes, Haemaphysalis, Dermacentor, Hyalomma, and Rhipicephalus, which are associated with particular vegetation zones of the country. The most important tick species of medical and veterinary concern are Ixodes persulcatus and Dermacentor nuttalli, which are found in northern boreal forests and central steppes, respectively. These tick species transmit a wide variety of TBPs, including tick-borne encephalitis virus, Borrelia, Anaplasma, and Rickettsia bacteria, and Babesia parasites infecting rodents, wild ungulates, livestock, and humans. Despite basic characteristics of the biology of ticks and TBPs in Mongolia being known, further research is needed to gain more precise and quantitative data on what tick species and TBPs are currently present within Mongolia, and their effects on human health and animal production.

Spatio-temporal analysis of peste des petits ruminants outbreaks in PR China (2013-2018): Updates based on the newest data

Peste des petits ruminants (PPR) is a highly contagious disease of small ruminants. The purpose of this study was to investigate the epidemic characteristics of PPR outbreaks in the People's Republic of China (PR China) from 2013 to 2018. A total of 41,876 PPR outbreaks were recorded in small ruminant populations in PR China during that period. Data from February to June 2018 were used to study new developments in the PPR epidemic in PR China. Spatio-temporal clusters and temporal distribution patterns were studied based on PPR notifications. We also used multiple logistic regression to examine the contribution of anthropogenic, climatic and topographic factors to PPR outbreaks. Distance to the nearest road (OR = 1.007 [95% CI: 1.001-1.014]), price of mutton (OR = 1.904 [95% CI: 1.358-2.668]) and mean monthly temperature in July (OR 1.156 = [95% CI: 1.110-1.204]) showed positive effects on PPR outbreaks. Negative effects were observed for number of large-scale farms (OR = 0.962 [95% CI: 0.940-0.985]). We also found that observed patterns of seasonality were characterized by peaks in April of 2014. Spatio-temporal clusters occurred in Yunnan, Jiangsu, Anhui, Heilongjiang province and Chongqing municipality. Hunan province reported PPR occurrences every year from 2014 to June 2018. Yunnan, Jiangsu and Anhui province have 56, 33 and 30 epidemic locations, respectively. PPR infections were first reported as the cause of death for 19 wild bharals in Qinghai province in 2018. All of this suggests that domestic trading of sheep and goats may be closely related to the spread of PPR. Prophylactic immunization in suspected animal populations or areas is recommended for the control of PPR and wild small ruminants should be monitored. Results presented here provide improved knowledge about PPR dynamics in PR China, which could be helpful in designing more effective prevention strategies.

Detection and molecular characterization of Peste des Petits Ruminants virus from outbreaks in Burundi, December 2017-January 2018

In December 2017, Peste des Petits Ruminants (PPR) emerged in Burundi (East Africa) and rapidly spread to five provinces (Gitega, Kirundo, Mwaro, Muramvya and Karuzi) in the country, causing severe disease and killing more than 4,000 goats in the province of Gitega alone. An initial outbreak investigation was conducted in December 2017 by the Burundi Government Veterinary Services and samples were collected for laboratory confirmation. A competitive Enzyme Linked Immuno-Sorbent Assay (cELISA: Chinese Patent No. ZL201210278970.9) supplied by the Lanzhou Veterinary Research Institute was used to test 112 sera and results showed around 37.5% positive samples. This high level of PPR positive sera in an animal population where PPR infection and vaccination had not been previously reported indicated the exposure of the animals to PPRV. Subsequently in January 2018, the laboratory tests conducted at the African Union-Pan African Veterinary Vaccine Centre (AU-PANVAC) laboratories following a joint investigative mission by the African Union-Interafrican Bureau for Animal Resources (AU-IBAR), AU-PANVAC and the East African Community (EAC) confirmed the presence of PPR in Burundi. Samples tested by conventional RT-PCR indicated the presence of the PPR virus (PPRV). Confirmatory isolation of the virus was also performed. Phylogenetic analysis revealed that the virus belongs to lineage III and shows a close relationship with PPRV isolates from Kenya in 2011 and Uganda in 2012. A possible explanation for the outbreaks of PPR in Burundi between December 2017 and February 2018 is presented.

Molecular characterization of Peste des Petits ruminants virus isolated from four outbreaks occurred in southern Iran

Background

Peste des petits ruminants (PPR) is a severe infectious disease in both domestic and wild small ruminants. Due to its heavy economic burden and hence social and health impacts on human populations, Food and Agriculture Organization of the United Nations (FAO) and The World Organization for Animal Health (OIE) have targeted PPR for eradication by 2030. In order to plan and implement a successful eradication program, factual status assessments prior to devising disease control strategies is a vital criterion. The aim of this study was to isolate and characterize PPR virus from a rising wave of outbreaks in southern Iran.

Results

Twenty-one clinical samples, including blood as well as oral, nasal and ocular swabs were collected from ten sick animals in 4 various herds and were examined with ELISA and RT-PCR for the presence of PPR virus antigen and genome, respectively. The virus was successfully isolated in primary lamb kidney cell culture and identified by RT-PCR. Phylogenetic analysis of the sequenced N genes revealed that, while the earliest reports of Iran’s outbreaks were grouped into clusters with Saudi Arabia, Turkey and Africa, in this study reported sequences were grouped with samples from Pakistan, Tajikistan and China in particular. This observation suggests a shift in PPRV flow from the western borders of the country to the eastern neighboring countries.

Conclusions

Lineage IV of PPR virus is presently circulating in Iran, with certain levels of genetic diversity. Present study along with previous reports demonstrates the dispersal patterns and movements of PPR virus, which highlights the reversal pattern of virus flow in recent years. Such information is necessary to understand PPRV molecular epidemiology and to develop more proper control strategies to eradicate the disease in the planned time.

Electronic supplementary material

The online version of this article (10.1186/s12917-019-1920-y) contains supplementary material, which is available to authorized users.

Pathological and molecular characterisation of peste des petits ruminants in Nubian ibex (Capra nubiana) in Israel

Peste des petits ruminants (PPR) is a devastating disease that generally affects sheep and goats, mostly in Asia, the Middle East and Africa. The disease has been declared a target for global eradication. Despite its high prevalence in domestic flocks and its high seroprevalence among wildlife, it is rarely reported as a fulminant disease in wild ruminant species (with the exception of Central Asia). In this report, we describe a severe PPR outbreak in a zoo herd of Nubian ibex (Capra nubiana), causing the deaths of 2/3 of the herd. The clinical onset was acute with morbid animals exhibiting lethargy and watery-to-bloody diarrhea and death usually within 48 h. The most consistent gross pathologic findings were hemorrhagic abomasitis and enteritis. Oral lesions and pulmonary lesions were rare. Histology revealed necrohemorrhagic enteritis and abomasitis with myriad nuclear and cytoplasmic viral inclusion bodies. Molecular examinations confirmed the diagnosis of PPR and determined that the causative agent belongs to lineage IV. Further molecular examination showed that the virus belongs to the Asian clade of lineage IV and is closely related to a virus described in Turkey.

Optimization and evaluation of a non-invasive tool for peste des petits ruminants surveillance and control

Peste des petits ruminants (PPR) is a highly contagious and devastating viral disease affecting mainly sheep and goats, but also a large number of wild species within the order Artiodactyla. A better understanding of PPR transmission dynamics in multi-host systems is necessary to efficiently control the disease, in particular where wildlife and livestock co-occur. Notably, the role of wildlife in PPR epidemiology is still not clearly understood. Non-invasive strategies to detect PPR infection without the need for animal handling could greatly facilitate research on PPR epidemiology and management of the disease in atypical hosts and in complex field situations. Here, we describe optimized methods for the direct detection of PPR virus genetic material and antigen in fecal samples. We use these methods to determine the detection window of PPR in fecal samples, and compare the sensitivity of these methods to standard invasive sampling and PPR diagnostic methods using field samples collected at a wildlife-livestock interface in Africa. Our results show that quantitative reverse transcription PCR (RT-QPCR) amplification of PPRV from fecal swabs has good sensitivity in comparison to ocular swabs. Animals infected by PPRV could be identified relatively early on and during the whole course of infection based on fecal samples using RT-QPCR. Partial gene sequences could also be retrieved in some cases, from both fecal and ocular samples, providing important information about virus origin and relatedness to other PPRV strains. Non-invasive strategies for PPRV surveillance could provide important data to fill major gaps in our knowledge of the multi-host PPR epidemiology.

Molecular characterization of peste-des-petits ruminants virus from Nepal, 2005 to 2016

Outbreaks of peste-des-petits ruminants (PPR) has been reported regularly in Nepal since 1994. Despite this, there has been limited molecular characterization of circulating virus in the country. In this study a 351 bp segment of the nucleoprotein gene of the PPR virus (PPRV) was amplified and sequenced from ten samples collected between 2005 and 2016. Phylogenetic trees were estimated from these sequences using the maximum likelihood method confirming that all of the PPRV from the samples analysed belonged to the sub-clade IV of clade I of lineage IV and that they shared a common origin with other PPRV isolates in the region.

Rapidly assessing the risks of infectious diseases to wildlife species

Predicting the likelihood of rare events is increasingly demanded by risk managers. A key challenge is dealing with different types of uncertainty, including epistemic uncertainties (lack of knowledge), stochasticity (inherent randomness) and natural variation. One potentially catastrophic event which is impacted by high levels of all three of these uncertainty types is the transmission of livestock pathogens to wildlife, particularly for endangered species. There is often a lack of basic information, e.g. about a given pathogen's presence in local livestock populations or the susceptibility of a given wildlife species to infection by the pathogen. We adapted the OIE (World Organisation for Animal Health) risk assessment framework to rapidly assess and prioritize the risks of livestock pathogens for wildlife, taking account of epistemic uncertainties, stochasticity, seasonal movement of animals and interaction between different species at different spatial and temporal scales. We demonstrate the approach using the endangered saiga antelope (Saiga tatarica tatarica) as a case study. We conclude that, in general, transmission events are likely to be rare and limited to small geographical areas; however, their impact could be high. Brucella spp. and foot-and-mouth disease virus are among those most likely to be transmitted from livestock to the Betpak-Dala saiga population.

Reverse Genetics for Peste des Petits Ruminants Virus: Current Status and Lessons to Learn from Other Non-segmented Negative-Sense RNA Viruses

Peste des petits ruminants (PPR) is a highly contagious transboundary animal disease with a severe socio-economic impact on the livestock industry, particularly in poor countries where it is endemic. Full understanding of PPR virus (PPRV) pathobiology and molecular biology is critical for effective control and eradication of the disease. To achieve these goals, establishment of stable reverse genetics systems for PPRV would play a key role. Unfortunately, this powerful technology remains less accessible and poorly documented for PPRV. In this review, we discussed the current status of PPRV reverse genetics as well as the recent innovations and advances in the reverse genetics of other non-segmented negative-sense RNA viruses that could be applicable to PPRV. These strategies may contribute to the improvement of existing techniques and/or the development of new reverse genetics systems for PPRV.

Genetic characterization of small ruminant morbillivirus from recently emerging wave of outbreaks in Pakistan

Peste des petits ruminants (PPR) is an endemic and highly infectious disease of several tropical countries, including Pakistan. Despite exhaustive vaccination, outbreaks are on the rise annually across different parts of the country. Clinical outcomes are largely employed to diagnose disease, while comprehensive genomic features of prevailing field strains of SRMV largely remain elusive. Here, we present comparative sequence-based phylogenomics of field strains from three districts representing different agro-livestock production systems during an emerging wave of outbreaks in 2015, together with the first complete genome sequencing of a strain from Pakistan. The analysis revealed clustering of study strain (SRMV/Lahore/UVAS/Pak/2015) to lineage IV, close to isolates characterized previously from India and China. Investigations of inter- and intralineage genetic distances showed a higher genetic distance between SRMV/Lahore/UVAS/Pak/2015 to lineage III viruses than lineages I and II. The characterized Pakistani strain also showed a high percentage of genetic distance from isolates originated from Nigerian and other African small ruminants. Based on these observations, an integrated cross-protection investigation is warranted in the future, not only to define the protective efficacy of currently applied vaccines, but also to continuously elucidate the genomic and evolutionary nature of circulating viruses in the country to achieve disease eradication by 2030.

Peste des petits ruminants in China since its first outbreak in 2007: A 10-year review

Peste des petits ruminants (PPR) is a highly infectious disease of small ruminants and caused by small ruminant morbillivirus (SRMV), formerly called peste-des-petits-ruminants virus (PPRV). This disease is circulating in Africa (except most countries in southern Africa), the Arabian Peninsula, the Middle East, and Central, East and South-East Asia. Peste des petits ruminants is still regarded as an exotic disease in China, where its first outbreak was reported in the Ngari region of Tibet in 2007, but effectively controlled by slaughter, vaccination and animal movement restriction in PPR-infected areas. However, PPR re-emerged in Xinjiang of China in December 2013, rapidly spread into much of China in the first half of 2014, but since then was substantially inhibited countrywide. Phylogenetic analysis shows that SRMVs from China share the highest homology with others from its neighbouring countries, possibly indicating the transboundary transmission of SRMVs. In 2015, a national eradication program for PPR was issued and has been being implemented in China, expecting to achieve a PPR-eradicating aim countrywide by 2020. Here, we reviewed a 10-year history (2007-2017) of PPR in China, including two major outbreaks, its infection in wild species, development of diagnostics and vaccines, and implementation of the national eradication program.

Saigas on the brink: Multidisciplinary analysis of the factors influencing mass mortality events

In 2015, more than 200,000 saiga antelopes died in 3 weeks in central Kazakhstan. The proximate cause of death is confirmed as hemorrhagic septicemia caused by the bacterium Pasteurella multocida type B, based on multiple strands of evidence. Statistical modeling suggests that there was unusually high relative humidity and temperature in the days leading up to the mortality event; temperature and humidity anomalies were also observed in two previous similar events in the same region. The modeled influence of environmental covariates is consistent with known drivers of hemorrhagic septicemia. Given the saiga population's vulnerability to mass mortality and the likely exacerbation of climate-related and environmental stressors in the future, management of risks to population viability such as poaching and viral livestock disease is urgently needed, as well as robust ongoing veterinary surveillance. A multidisciplinary approach is needed to research mass mortality events under rapid environmental change.