Pox outbreaks in Sheep and Goats at Makhdoom (Uttar Pradesh), India: Evidence of Sheeppox Virus Infection in Goats

Epidemiological, Pathological, and Molecular Studies on Sheeppox Disease Outbreaks in Karnataka, India

An epidemiological study spanning twelve years has revealed that sheeppox disease is both widespread and endemic, predominantly surging during the winter and summer seasons. This investigation focused on sheeppox across 11 field outbreaks, involving 889 animals from non-migratory flocks across six districts in Karnataka, in the southern peninsula of India. Among these, 105 animals exhibited clinical signs suggestive of sheeppox, such as lesions on the body, and 95 cases were confirmed through PCR testing. The overall positivity rate for sheeppox stood at 10.68% (95 out of 889 animals). The incidence of sheeppox was notably higher in animals aged between 1 and 2 years and was more prevalent in females. Affected animals displayed symptoms including respiratory distress, weakness, fever, loss of appetite, depression, and various skin lesions ranging from papular to pock lesions across their bodies. There was a significant increase in total leukocyte count, while hemoglobin levels, red blood cell counts, and hematocrit values significantly decreased. On gross examination, sheeppox lesions, varying from vesicular to nodular forms, were predominantly found on hairless areas of the body. Microscopic examination of skin lesions revealed extensive changes, such as hyperkeratosis, parakeratosis, acanthosis, hydropic degeneration, and necrosis of epithelial cells, along with characteristic intracytoplasmic viral inclusions. The lungs exhibited type-II pneumocyte hyperplasia and proliferative bronchiolitis, also with intracytoplasmic inclusions. Confirmation of the sheeppox virus was achieved through PCR and subsequent sequence analysis. Phylogenetic analysis of the full-length P32 and RPO30 gene demonstrated homology with sheeppox isolates from various parts of India and neighboring countries, indicating that Indian sheeppox viruses are highly lineage-specific and correlate with the host of origin. Based on these findings, it is recommended to implement a homologous vaccination strategy, utilizing selective host/viral strains to enhance protection in susceptible animals.

Lessons Learned from Active Clinical and Laboratory Surveillance during the Sheep Pox Virus Outbreak in Spain, 2022-2023

In September 2022, more than 50 years after its eradication from Spain, Sheep pox virus was confirmed by laboratory analysis in sheep showing characteristic lesions. This was the start of an outbreak that lasted 9 months and infected 30 farms dispersed over two different areas, Andalusia and Castilla-La Mancha. Early after the initial confirmation, an active surveillance based on clinical inspection with laboratory confirmation of sheep with clinical signs was started in restricted areas. This allowed the confirmation of Sheep pox in 22 out of 28 suspected farms, where limited numbers of sheep with mainly erythema and papules were found, indicative of early detection. Nevertheless, to improve active surveillance and stop the outbreak, clinical inspection was reinforced by laboratory analysis in all inspected farms, even when no clinically diseased sheep were detected. Although more than 35,000 oral swabs from 335 farms were analysed by real-time PCR in pools of five, only two out of six reported outbreaks in this period were detected by laboratory analysis before clinical signs were observed. Furthermore, additional insights were gained from the extensive laboratory surveillance performed on samples collected under field conditions. No evidence of Sheep pox virus infection was found in goats. Oral swabs proved to be the sample of choice for early detection in the absence of scabs and could be tested in pools of five without extensive loss in sensitivity; serology by ELISA was not useful in outbreak detection. Finally, a non-infectious genome of the virus could be detected months after cleaning and disinfection; thus, real-time PCR results should be interpreted with caution in sentinel animals during repopulation. In conclusion, the outbreak of Sheep pox virus in Spain showed that active clinical inspection with laboratory confirmation of clinically diseased sheep via oral swab testing proved a sensitive method for detection of infected farms, providing insights in laboratory surveillance that will be helpful for other countries confronted with Sheep pox outbreaks.

Poxviruses from the Concept of One Health

In the last 4 years, the world has experienced two pandemics of bat-borne viruses. Firstly, in 2019 the SARS-CoV-2 pandemic started and has been causing millions of deaths around the world. In 2022, a Monkeypox pandemic rose in various countries of the world. Those pandemics have witnessed movements and initiatives from healthcare and research institutions to establish a worldwide understanding to battle any future pandemics and biological threats. One Health concept is a modern, comprehensive, unifying ways to improve humans, animals, and ecosystems' health. This concept shows how much they are intertwined and related to one another, whether it is an environmental, or a pathological relation. This review aims to describe Poxviridae and its impact on the One Health concept, by studying the underlying causes of how poxviruses can affect the health of animals, humans, and environments. Reviewing the effect of disease transmission between animal to human, human to human, and animal to animal with pox viruses as a third party to achieve a total understanding of infection and viral transmission. Thus, contributing to enhance detection, diagnosis, research, and treatments regarding the application of One Health.

The emergence of novel Iranian variants in sheeppox and goatpox viral envelope proteins with remarkably altered putative binding affinities with the host receptor

The outbreak of Sheep and goat pox (SGP) viral infections have increasingly been reported despite vaccinating the majority of sheep populations in Iran. The objective of this study was to predict the impacts of the SGP P32/envelope variations on the binding with host receptors as a candidate tool to assess this outbreak. The targeted gene was amplified in a total of 101 viral samples, and the PCR products were subjected to Sanger sequencing. The polymorphism and phylogenetic interactions of the identified variants were assessed. Molecular docking was performed between the identified P32 variants and the host receptor and the effects of these variants were evaluated. Eighteen variations were identified in the investigated P32 gene with variable silent and missense effects on the envelope protein. Five groups (G1-G5) of amino acid variations were identified. While there were no amino acid variations in the G1 (wild-type) viral protein, G2, G3, G4, and G5 proteins had seven, nine, twelve, and fourteen SNPs, respectively. Based on the observed amino acid substitutions, multiple distinct phylogenetic places were occupied from the identified viral groups. Dramatic alterations were identified between G2, G4, and G5 variants with their proteoglycan receptor, while the highest binding was revealed between goatpox G5 variant with the same receptor. It was suggested that the higher severity of goatpox viral infection originated from its higher affinity to bind with its cognate receptor. This firm binding may be explained by the observed higher severity of the SGP cases from which G5 samples were isolated.

Genetic characterization of sheep pox virus strains from outbreaks in Central Russia in 2018-2019

This study investigates the phylogenomic relatedness between sheep pox viruses (SPPVs) circulating in Central Russia in 2018-2019 with the NISKHI vaccine strain used in the country, based on their complete genome sequences. The sheep pox outbreaks occurred 1 year apart in the adjacent regions of Tula and Moscow. Full genome sequences were generated by sequencing DNA directly obtained from Trizol-extracted scabs, using the DNBSEQ-400 platform (MGI Tech, China). Phylogenetic analysis indicated that the SPPV isolates from Russia clusters with previously published sequences from Srinagar in the Kashmir province of India in 2000 (SPPV-Srinagar strain) as well as SPPV A strain from Kazakhstan in 2000. The aforementioned cluster belonged to a sister clade containing the NISKHI vaccine strain, thus indicating that the recent outbreaks were not genetically linked to the widely used vaccine.

Assessment of the control measures of the category A diseases of Animal Health Law: sheep and goat pox

EFSA received a mandate from the European Commission to assess the effectiveness of some of the control measures against diseases included in the Category A list according to Regulation (EU) 2016/429 on transmissible animal diseases ('Animal Health Law'). This opinion belongs to a series of opinions where these control measures will be assessed, with this opinion covering the assessment of control measures for sheep and goat pox. In this opinion, EFSA and the AHAW Panel of experts review the effectiveness of: (i) clinical and laboratory sampling procedures, (ii) monitoring period and (iii) the minimum radii of the protection and surveillance zones, and the minimum length of time the measures should be applied in these zones. The general methodology used for this series of opinions has been published elsewhere; nonetheless, the transmission kernels used for the assessment of the minimum radii of the protection and surveillance zones are shown. Several scenarios for which these control measures had to be assessed were designed and agreed prior to the start of the assessment. Different risk-based sampling procedures based on clinical visits and laboratory testing are assessed in case of outbreak suspicion, granting animal movements and for repopulation purposes. The monitoring period of 21 days was assessed as effective. The estimated probability of transmission beyond the protection zone of 3 km radius from an infectious establishment is 9.6% (95% CI: 3.1-25.8%) and 2.3% (95% CI: 1-5.5%) for the surveillance zone of 10 km radius. This may be considered sufficient to contain the disease spread (95% probability of containing transmission corresponds to 5.3 Km). To contain 99% of the spread, the radius should be increased to 19.4 km (95% CI: 9.8-26.8). This may increase the number of farms in the surveillance zone, since the area would increase fourfold.

Review of sheep and goat pox disease: current updates on epidemiology, diagnosis, prevention and control measures in Ethiopia

Sheep pox, goat pox, and lumpy skin diseases are economically significant and contagious viral diseases of sheep, goats and cattle, respectively, caused by the genus Capripoxvirus (CaPV) of the family Poxviridae. Currently, CaPV infection of small ruminants (sheep and goats) has been distributed widely and are prevalent in Central Africa, the Middle East, Europe and Asia. This disease poses challenges to food production and distribution, affecting rural livelihoods in most African countries, including Ethiopia. Transmission occurs mainly by direct or indirect contact with infected animals. They cause high morbidity (75-100% in endemic areas) and mortality (10-85%). Additionally, the mortality rate can approach 100% in susceptible animals. Diagnosis largely relies on clinical symptoms, confirmed by laboratory testing using real-time PCR, electron microscopy, virus isolation, serology and histology. Control and eradication of sheep pox virus (SPPV), goat pox virus (GTPV), and lumpy skin disease (LSDV) depend on timely recognition of disease eruption, vector control, and movement restriction. To date, attenuated vaccines originating from KSGPV O-180 strains are effective and widely used in Ethiopia to control CaPV throughout the country. This vaccine strain is clinically safe to control CaPV in small ruminants but not in cattle which may be associated with insufficient vaccination coverage and the production of low-quality vaccines.

The role of wildlife in the epidemiology and control of Foot-and-mouth-disease And Similar Transboundary (FAST) animal diseases: A review

Transboundary Animal Diseases (TADs) are notifiable diseases which are highly transmissible and have the potential for rapid spread regardless of national borders. Many TADs are shared between domestic animals and wildlife, with the potential to affect both livestock sector and wildlife conservation and eventually, public health in the case of zoonosis. The European Commission for the Control of Foot-and-Mouth Disease (EuFMD), a commission of the Food and Agriculture Organization of the United Nations (FAO), has grouped six TADs as 'Foot-and-mouth disease (FMD) And Similar Transboundary animal diseases' (FAST diseases). FAST diseases are ruminant infections caused by viruses, for which vaccination is a control option. The EuFMD hold-FAST strategy aims primarily at addressing the threat represented by FAST diseases for Europe. Prevention and control of FAST diseases might benefit from assessing the role of wildlife. We reviewed the role of wildlife as indicators, victims, bridge hosts or maintenance hosts for the six TADs included in the EuFMD hold-FAST strategy: FMD, peste des petits ruminants, lumpy skin disease, sheep and goatpox, Rift Valley fever and bovine ephemeral fever. We observed that wildlife can act as indicator species. In addition, they are occasionally victims of disease outbreaks, and they are often relevant for disease management as either bridge or maintenance hosts. Wildlife deserves to become a key component of future integrated surveillance and disease control strategies in an ever-changing world. It is advisable to increase our knowledge on wildlife roles in relevant TADs to improve our preparedness in case of an outbreak in previously disease-free regions, where wildlife may be significant for disease surveillance and control.

Transboundary Animal Diseases, an Overview of 17 Diseases with Potential for Global Spread and Serious Consequences

Animals provide food and other critical resources to most of the global population. As such, diseases of animals can cause dire consequences, especially disease with high rates of morbidity or mortality. Transboundary animal diseases (TADs) are highly contagious or transmissible, epidemic diseases, with the potential to spread rapidly across the globe and the potential to cause substantial socioeconomic and public health consequences. Transboundary animal diseases can threaten the global food supply, reduce the availability of non-food animal products, or cause the loss of human productivity or life. Further, TADs result in socioeconomic consequences from costs of control or preventative measures, and from trade restrictions. A greater understanding of the transmission, spread, and pathogenesis of these diseases is required. Further work is also needed to improve the efficacy and cost of both diagnostics and vaccines. This review aims to give a broad overview of 17 TADs, providing researchers and veterinarians with a current, succinct resource of salient details regarding these significant diseases. For each disease, we provide a synopsis of the disease and its status, species and geographic areas affected, a summary of in vitro or in vivo research models, and when available, information regarding prevention or treatment.

Evidence of Transmission of Goatpox between Domestic Goats and Wild Himalayan Goral (Naemorhedus goral) in Arunachal Pradesh, India

Examination of carcasses of Himalayan goral (Naemorhedus goral) revealed nodular, pox-like eruptions in the skin. Similar disease was also seen in domestic goats (Capra aegagrus hircus) in the same area. Goatpox virus was identified as the etiology of the disease in both cases, with probable transmission between the species.

Molecular phylogenetics of a recently isolated goat pox virus from Vietnam

Background

After a decade of silence, an outbreak of the contagious and Asian endemic disease, goat pox re-emerged in North Vietnam affecting more than 1800 heads with a mortality rate of 6.5%. The inevitable impact of goat pox on hide quality, breeding, chevon and milk production has resulted in a significant economic losses to the developing goat industry of Vietnam. In the act of establishing an effective control of this devastating disease, tracing the source of re-emergence via a phylogenetic study was carried out to reveal their genetic relatedness. Either skin scab or papule from the six affected provinces were collected, cultured into Vero cells followed by restricted enzyme digestion of targeted P32 gene DNA encoding. The P32 gene was then cloned and transformed into E.coli competent cells for further sequencing.

Results

The isolated sequence is deposited into GenBank under Accession No. MN317561/VNUAGTP1. The phylogenetic tree revealed high similarity of nucleotide and amino acid sequences to references goat pox strains accounting for 99.6 and 99.3, respectively. The Vietnamese strain is clustered together with currently circulating goat pox virus in China, India and Pakistan which suggested the origin of South China.

Conclusions

This Vietnam isolate is clustered together with other Asian goat pox strains indicating the dissemination of a common goat pox virus within this continent.

Here, There, and Everywhere: The Wide Host Range and Geographic Distribution of Zoonotic Orthopoxviruses

The global emergence of zoonotic viruses, including poxviruses, poses one of the greatest threats to human and animal health. Forty years after the eradication of smallpox, emerging zoonotic orthopoxviruses, such as monkeypox, cowpox, and vaccinia viruses continue to infect humans as well as wild and domestic animals. Currently, the geographical distribution of poxviruses in a broad range of hosts worldwide raises concerns regarding the possibility of outbreaks or viral dissemination to new geographical regions. Here, we review the global host ranges and current epidemiological understanding of zoonotic orthopoxviruses while focusing on orthopoxviruses with epidemic potential, including monkeypox, cowpox, and vaccinia viruses.

Comparative analysis of ankyrin (ANK) genes of five capripoxviruses isolate strains from Xinjiang province in China

Background

Sheeppox and goatpox are both economically important animal diseases in which pathogens are goatpox virus (GTPV) and sheeppox virus (SPPV). They can’t cause cross-species infection between sheep and goats in general. But in recent decades, the infection of sheep by goatpox or goats by sheeppox has been reported. The literature has indicated that the occurrence of these cases has a significant and direct relationship with mutations of ankyrin genes families (ANK genes 010,138,140,141.2,145) located in two-terminal regions of capripoxvirus genomes. So it is very important to decipher these nucleotides and their coding amino acid sequences of the five genes regarded as host range and virulence factors for effective prevention and control of capripoxvirus diseases.

Methods

In this study, all the ankyrin genes of three goatpox virus, two sheeppox virus, and one GTPV vaccine strains from Nanjiang areas of Xinjiang province of China during 2010–2011 were collected, amplified, cloned and sequenced. The sequence of every ankyrin genes has been compared with not only sequences from six viruses but also all sequences from three species of capripoxvirus genus from Gene bank, and every ANK gene’s mutated nucleotides and amino acids have been screened, and the relationship of genetic evolution among different virus strains has been analyzed, as well as the domain architecture of these genes was forecasted and analyzed.

Results

The six capripoxvirus strains can be well-distinguished GTPV and SPPV based on five ANK genes’ sequence identicalness except for GTPV-SS strain, which showed higher identicalness with SPPV. The ANK gene sequence of the GTPV-SS strain was 100% identical with SPPV-M1 (ANK138,140,145) and SPPV-M2 (ANK138,145), respectively. Phylogenetically, these six capripoxvirus strains were also grouped into the same cluster of India reference strains in lineages and showed extreme identical conservative or variable regions with India capripoxvirus isolates by sequence alignment. Moreover, for the functional domains, these ANK genes of capripoxvirus except for ANK gene 145, are identical in size, and ANK genes 145 of SPPV are usually 100 bp (approximately 30 aa) longer than those of GTPV and eventually form a PRANC domain at C-terminus.

Conclusions

The isolated strain of GTPV-SS may be a cross-species infection or the collected material was contaminated, and the inferred Capripox outbreak in Xinjiang in 2010 can be introduced from India. ANK genes 138,140,141.2 and 145 of capripoxvirus can be used as the target genes to identify GTPV and SPPV. Moreover, the four ANK genes determining the host range are more significant than the ANK gene 010. These ANK genes play combining roles for their function.

Molecular phylogeny of Capripoxviruses based on major immunodominant protein (P32) reveals circulation of host specific sheeppox and goatpox viruses in small ruminants of India

Sheeppox and goatpox are highly contagious viral diseases of small ruminants causing severe economic losses to the livestock farmers. The disease is enzootic in Asia including India, Middle East and African countries. In the present study, a total of 28 isolates from twenty five sheeppox and goatpox disease outbreaks were phylogenetically analyzed based on P32 gene/protein along with homology modeling and docking using heparan sulfate and UDP-glucose. Three distinct lineage-specific clusters as per their host origin were recorded. Multiple sequence analysis of P32 gene revealed that genetically similar sheeppox virus (SPPV) and goatpox virus (GTPV) strains are circulating in India. Phylogenetically, Lumpy skin disease (LSDV) and SPPV had a closer genetic relationship than GTPV. Comparative sequence alignment indicated conservation of various motifs such as glycosaminoglycan (GAG), chemokine like motif (CX3C) and Asp-Glu-any other residue-Asp (D/ExD), as well as viral specific signature residues in SPPV and GTPV isolates. Structurally, P32 protein of SPPV and GTPV with mixed α helices and β sheets resembled with crystal structure of homologue vaccinia virus H3L protein. Docking studies in P32 protein of SPPV and GTPV revealed conserved binding pattern with heparan sulfate which is involved in the virus attachment and varied glycosyltransferase fold with UDP-glucose. These findings may help in development of suitable vaccines/diagnostics and therapeutics against capripoxviruses.

Comparative sequence and structural analysis of the ORF095 gene, a vaccinia virus A4L homolog of capripoxvirus in sheep and goats

Sheeppox and goatpox are important transboundary animal viral diseases of sheep and goats caused by sheeppox virus (SPPV) and goatpox virus (GTPV), respectively, of the genus Capripoxvirus, family Poxviridae. Among the proteins encoded by the capripoxvirus (CaPV) genome, ORF095 (vaccinia virus A4L homolog) is an immunodominant virion core protein that plays a pivotal role in virus assembly and morphogenesis. In the present study, sequence analysis of the ORF095 genes of 27 SPPV and GTPV isolates or field samples from different geographical regions of India was performed, and structure was prediction was done by homology modeling. A multiple sequence alignment of different CaPV isolates revealed that CaPV-A4L is highly conserved, with several species-specific signature residues, namely A93, A216, A315, G136 and G146 in GTPV, G47, A63, A168 and A276 in SPPV, and G48 and C98 in lumpy skin disease virus (LSDV). Phylogenetically, the CaPV isolates were separated into three major clusters, GTPV, SPPV and LSDV, based on the complete coding sequence of the CaPV-A4L gene. Genus-specific clustering of poxviruses was observed in phylogenetic analysis based on A4L protein homologs of chordopoxviruses. A secondary structure prediction showed the presence of six α-helices and one β-sheet as well as some coils. The signature residues identified here are potentially useful for genotyping, and the predicted characteristics of the CaPV-A4L protein make it an ideal candidate for use as an immunogenic or diagnostic antigen for the development of immunoassays in  the sero-evaluation of CaPV in target hosts.

Tetra-primer amplification refractory mutation system-polymerase chain reaction (TARMS-PCR) assay in genotyping of single nucleotide polymorphism in goatpox virus p32 gene

Single nucleotide polymorphisms (SNPs) are most often associated with some pathological implications. Screening out the presence of such mutations is extremely sought to know the nature of the disease outbreak. Furthermore, the allele specific distributions of the virus are to be known for effective epidemiological strategies. Tetra-primer amplification refractory mutation system-polymerase chain reaction (TARMS-PCR) is a simple, rapid and inexpensive technique as compared to high thoroughput sequencing methods for genotyping SNPs. In the present report, a novel TARMS-PCR was utilized to ascertain the presence of a particular allele (645GTPVC/T) in the p32 gene of goatpox virus (GTPV), one of the most widespread Capripoxvirus affecting small ruminants exhibiting moderate to even severe pathological consequences in the endemic areas. It was found that GTPV of Chinese origin are GTPVC/T type whereas only single genotype (GTPVT) was found among GTPV of Indian origins. Possibly, this is the first report of development of a TARMS-PCR technique for genotyping of virus to ascertain the presence of a specific allele. This technique can be applied further to unveil the presence of deleterious mutations in any other viral genome. Further, this technique can be applied for cross-border surveillance of GTPV among China and India.

Molecular characterization of sheeppox virus from outbreaks in Karnataka, India

AIM

This study aimed to characterize sheeppox virus (SPPV) using the P32 gene of the Capripoxvirus (CaPVs).

MATERIALS AND METHODS

Clinical samples of skin, scabs, and nasal swab from suspected outbreaks Horalagallu (n=13) and Gerahalli (n=11) at Ramanagara district in Karnataka were collected. All the samples were initially subjected to genus-specific diagnostic polymerase chain reaction (PCR). The pooled clinical samples from each outbreak were also subjected to virus isolation. The isolates were confirmed by CaPVs genotyping PCR targeting the full-length P32 gene, followed by sequencing and phylogenetic analysis.

RESULTS

The clinical signs and lesions varied from mild to severe degree with no specificity between age and sex. Specific cytopathic changes in cell morphology were observed in infected Vero cells from both outbreaks, which were confirmed by PCR. The complete P32 gene from two outbreaks was successfully amplified with the expected amplicon size of 1006bp. The sequencing and phylogenetic analysis revealed that both the outbreaks were due to SPPV and shared high similarity with published SPPVs from Karnataka and other parts of India.

CONCLUSION

The current study showed that complete P32 gene-based genotypic PCR assay can be used for genetic characterization and molecular epidemiology of both sheeppox and goatpox diseases and also to differentiate the causative agents. The sequence analysis revealed 100% similarity among the two outbreak isolates suggesting the same strain of the virus and common source of infection for the outbreaks.

Genetic studies of terminal regions of vaccine and field isolates of capripoxviruses

Sheeppox and goatpox are two of the most important diseases associated with significant economic loss and impact on animal trade. In spite of the use of vaccines, outbreaks are being reported on several occasions. Therefore, deciphering the host specificity and virulence of sheeppox virus (SPPV) and goatpox virus (GTPV) is important in developing effective vaccines. It is opined that genes located in the terminal regions play a major role in determining host range and/or virulence. In the present study, nine isolates (6 GTPV and 3 SPPV; included both vaccine and virulent viruses) were genetically characterized by targeting 11 genes (7 host-range and 4 virulence genes) which are located in the terminal regions of capripoxviruses. In the genetic analyses, it was observed that there are several nucleotide and amino acid signatures which are specific for either SPPV or GTPV. However, surprisingly, none of the 11 genes could be able to differentiate the vaccine and field viruses of GTPV and SPPV. Our study indicates that the genes of the terminal regions may have a role in determining the host-specificity but the involvemet in determinatin of virulence/attenuation is not certain at least for the isolates used in the current study. Therefore, it is likely that some other genes located in terminal/central regions may also play a role in determination of virulence and pathogenesis which needs to be confirmed by whole-genome sequencing of several vaccine and virulent viruses.

Spread and impact of goat pox ("sagolay bohonta") in a village smallholder community around Kaziranga National Park, Assam, India

During September and October 2017, a highly fatal outbreak of a disease clinically indistinguishable from goat pox occurred in the villages around the Kaziranga National Park, Assam, India. This was investigated through clinical examination of affected animals, individual interviews with goat keepers and participatory village meetings. Laboratory confirmation was impractical due to the isolation and poverty of the affected community and unnecessary due to the specific nature of the clinical signs. Respondents reported not having encountered the disease previously, and it would appear that a naïve local population developed within an endemically affected region because of a trend to avoid purchasing animals from outside the village. Local grazing practices appear to have had a role in both the spread and control of the outbreak. Goats are an important form of savings and cash income to people in the locality, and the outbreak may result in considerable financial hardship for affected goat keepers. We provide a detailed description of the clinical disease and the spread of the outbreak in the locality. Awareness of the disease with reference to farming practices will provide opportunities for future disease control to enhance animal welfare and rural prosperity.

VARV B22R homologue as phylogenetic marker gene for Capripoxvirus classification and divergence time dating

Sheeppox disease is associated with significant losses in sheep production world over. The sheep pox virus, the goatpox virus, and the lumpy skin disease virus cannot be distinguished by conventional serological tests. Identification of these pathogens needs molecular methods. In this study, seven genes viz. EEV maturation protein-F12L, Virion protein-D3R, RNA polymerase subunit-A5R, Virion core protein-A10L, EEV glycoprotein-A33R, VARV B22R homologue, and Kelch like protein-A55R that cover the start, middle, and end of the genome were selected. These genes were amplified from Roumanian-Fanar vaccine strain and Jaipur virulent strain, cloned, and sequenced. On analysis with the available database sequences, VARV B22R homologue was identified as a marker for phylogenetic reconstruction for classifying the sheeppox viruses of the ungulates. Further, divergence time dating with VARV B22R gene accurately predicted the sheeppox disease outbreak involving Jaipur virulent strain.

Molecular epidemiology of goat pox viruses

Goat pox disease outbreaks were observed in different places affecting Black Bengal Goats in West Bengal (WB) and Tellicherry, Vembur and non-descriptive breeds in Tamil Nadu (TN) causing severe lesions and mortality up to 30%. Clinical specimens from all the outbreaks were screened by polymerase chain reaction followed by restriction fragment length polymorphism (PCR-RFLP) and confirmed the diseases as Goat Pox. Virus isolation in Vero cell line was done with randomly selected ten samples, cytopathic effects (CPE) characterized by syncytia and intracytoplasmic inclusion bodies were observed after several blind passages. Nucleotide sequence of complete p32 gene using randomly selected two isolates and three clinical specimens revealed presence of Goat pox virus (GTPV)-specific signature residues in all the sequences. Phylogenetic analysis using the present five sequences along with GenBank data of GTPV complete p32 gene sequences showed all the GTPV sequences cluster together except Pellor strain (NC004003) and FZ Chinese strain (KC951854). The five sequences either from WB or TN cluster more closely with GTPV isolates of Maharashtra state that were responsible for cross species outbreak of pox disease in both sheep (KF468759) and goats (KF468762) in India during the year 2010. All the Indian goat pox viruses, including the Mukteswar strain, isolated in 1946 and sequence reported in 2004 clustered together with the GTPVs causing the recent outbreaks. It was observed that GTPVs caused similar clinical manifestation irrespective of their geographical locations and breed characteristics, no variation observed among the Indian isolates based on p32 gene over the period of seventy years and disease outbreaks could not be observed or reported in vaccinated goats.

Vaccinia Virus Natural Infections in Brazil: The Good, the Bad, and the Ugly

The orthopoxviruses (OPV) comprise several emerging viruses with great importance to human and veterinary medicine, including vaccinia virus (VACV), which causes outbreaks of bovine vaccinia (BV) in South America. Historically, VACV is the most comprehensively studied virus, however, its origin and natural hosts remain unknown. VACV was the primary component of the smallpox vaccine, largely used during the smallpox eradication campaign. After smallpox was declared eradicated, the vaccination that conferred immunity to OPV was discontinued, favoring a new contingent of susceptible individuals to OPV. VACV infections occur naturally after direct contact with infected dairy cattle, in recently vaccinated individuals, or through alternative routes of exposure. In Brazil, VACV outbreaks are frequently reported in rural areas, affecting mainly farm animals and humans. Recent studies have shown the role of wildlife in the VACV transmission chain, exploring the role of wild rodents as reservoirs that facilitate VACV spread throughout rural areas. Furthermore, VACV circulation in urban environments and the significance of this with respect to public health, have also been explored. In this review, we discuss the history, epidemiological, ecological and clinical aspects of natural VACV infections in Brazil, also highlighting alternative routes of VACV transmission, the factors involved in susceptibility to infection, and the natural history of the disease in humans and animals, and the potential for dissemination to urban environments.

Development and validation of a TaqMan probe-based real-time PCR method for the differentiation of wild type lumpy skin disease virus from vaccine virus strains

Lumpy skin disease (LSD) is a transboundary viral disease of cattle with severe economic impact. Immunization of cattle with homologous live attenuated vaccines poses a number of diagnostic problems, as it has been associated with adverse reactions resembling disease symptoms. The latter hampers clinical diagnosis and poses challenges in virus identification. To this end, a duplex quantitative real-time PCR method targeting the GPCR gene was developed and validated, for the concurrent detection and differentiation of wild type and vaccine Lumpy skin disease virus (LSDV) strains. The method was evaluated in three laboratories. The evaluation included a panel of 38 poxvirus isolates/strains and the analytical characteristics of the method were determined. Amplification efficiencies were 91.3% and 90.7%, for wild type and vaccine LSDV, respectively; the limit of detection was 8 DNA copies for both targets and the inter-assay CV was 0.30% for wild type and 0.73% for vaccine LSDV. The diagnostic performance was assessed using 163 LSDV-positive samples, including field specimens and samples from experimentally vaccinated/infected animals. The method is able to confirm diagnosis in suspect cases, it differentiates infected from vaccinated animals (DIVA) and can be regarded as an important tool for effective LSD surveillance and eradication during vaccination campaigns.

Detection of Peste des petits ruminants virus and goatpox virus from an outbreak in goats with high mortality in Meghalaya state, India

Aim:

We describe a laboratory investigation carried out to confirm the etiology of the heavy mortality (37 animals died out of total 44, i.e. 84%) in goats in Ri-Bhoi district of Meghalaya, Northeast region of India in December 2015. The clinical signs observed were abortion, diarrhea, high fever (up to 104°F), pox lesion in the skin, and respiratory distress.

Materials and Methods:

The samples comprising whole blood, sera, and pox lesion were collected from the animals (n=7) from an outbreak for the screening of peste des petits ruminants (PPR) and poxviruses. The whole blood and sera were used for screening of PPR virus (PPRV) by sandwich enzyme-linked immunosorbent assay (ELISA) and antibody by competitive ELISA as well as detection of PPRV partial N gene by reverse transcription-polymerase chain reaction (PCR). The skin lesions were used for the detection of poxvirus by PCR.

Results:

The results showed the presence of PPR antigens (58-80%) in the samples by sandwich ELISA and antibody in all the sera samples ranging from 9% to 41% positivity in competitive ELISA. Four samples were positive for PPRV partial N gene. The skin lesion screened for poxvirus was also found to be positive for I3L gene of goatpox virus.

Conclusion:

We confirm the outbreak of disease in goats with high mortality is a case of mixed infection of PPR and goatpox detected for the first time in Northeast India.

Infection of goats with goatpox virus triggers host antiviral defense through activation of innate immune signaling

Goatpox, caused by goatpox virus (GTPV), is one of the most serious infectious diseases associated with high morbidity and mortality in goats. However, little is known about involvement of host innate immunity during the GTPV infection. For this, goats were experimentally infected with GTPV. The results showed that GTPV infection significantly induced mRNA expression of type I interferon (IFN)-α and IFN-β in peripheral blood lymphocytes, spleen and lung. In addition, GTPV infection enhanced expression of several inflammatory cytokines, including interleukin (IL)-1β, IL-6, IL-18; and tumor necrosis factor-α (TNF-α). Strikingly, infection with GTPV activated signal transducers and activators of transcription 3 (STAT3), a critical cytokine signaling molecule. Interestingly, the virus infection induced expression of suppressor of cytokine signaling (SOCS)-1. Importantly, the infection resulted in an increased expression of some critical interferon-stimulated genes, such as interferon-induced transmembrane protein (IFITM) 1, IFITM3, interferon stimulated gene (ISG) 15 and ISG20. Furthermore, we found that infection with GTPV up-regulated expression of Toll-like receptor (TLR) 2 and TLR9. These results revealed that GTPV infection activated host innate immune signaling and thereby triggered antiviral innate immunity. The findings provide novel insights into complex mechanisms underlying GTPV-host interaction and pathogenesis of GTPV.

Development and evaluation of loop-mediated isothermal amplification assay for rapid detection of Capripoxvirus

Aim:

The present study was undertaken to develop a nucleic acid-based diagnostic assay loop-mediated isothermal amplification assay (LAMP) targeting highly conserved genomic regions of Capripoxvirus (CaPVs) and its comparative evaluation with real-time polymerase chain reaction (PCR).

Material and Methods:

Lyophilized vaccine strain of sheeppox virus (SPPV) was used for optimization of LAMP assay. The LAMP assay was designed using envelope immunogenic protein (P32) coding gene targeting highly conserved genomic regions of CaPV responsible for causing sheep pox, goat pox, and lumpy skin disease in sheep, goat and cattle respectively. Serial tenfold dilution of SPPV recombinant plasmid DNA was used for a calculating limit of detection. Analytical sensitivity and specificity were performed.

Results:

The test described is quick (30 min), sensitive and specific for detection of CaPVs. The described assay did not show any cross-reactivity to other related viruses that cause apparently similar clinical signs. It was found to be ten times more sensitive than conventional PCR however, 100 times less sensitive than quantitative PCR (qPCR). LAMP assay results were monitored by color change method using picogreen dye and agarose gel electrophoresis.

Conclusion:

LAMP assay can be a very good alternative for CaPV detection to other molecular techniques requiring sophisticated equipments.

Detection and characterization of atypical capripoxviruses among small ruminants in India

Recent developments in molecular biology shed light on cross-species transmission of SPPV and GTPV. The present study was planned to characterize the capripoxviruses which were circulating in the field condition among sheep and goats using RPO30 gene-based viral lineage (SPPV/GTPV) differentiating PCR and sequencing of RPO30 and GPCR genes from clinical samples. Out of 58 scabs (35 sheep and 23 goats) screened, 27 sheep and 18 goat scabs were found positive for capripox virus infections. With the exception of one sheep and one goat scabs, all the positive samples yielded amplicon size according to host origin, i.e. SPPV in sheep and GTPV in goats. In the above two exceptional cases, goat scab and sheep scab yielded amplicon size as that of SPPV and GTPV, respectively. Further, sequencing and phylogenetic analyses of complete ORFs of RPO30 and GPCR genes from six sheep and three goat scabs revealed that with the exception of above two samples, all had host-specific signatures and clustered according to their host origin. In case of cross-species infecting samples, sheep scab possessed GTPV-like signatures and goat scab possessed SPPV-like signatures. Our study identifies the circulation of cross-infecting SPPV and GTPV in the field and warrants the development of single-strain vaccine which can protect the animals from both sheeppox and goatpox diseases.

Investigation of a Possible Link Between Vaccination and the 2010 Sheep Pox Epizootic in Morocco

Sheep pox is endemic in most parts of Northern Africa and has the potential to cause severe economic problems. Live attenuated vaccines are used in Morocco, and in many other countries, to control the disease. Sheep pox virus (SPPV) re-appeared in 2010 causing a nodular clinical form previously not observed in Morocco. The severe clinical signs observed during the course of this outbreak and initial reports citing similarity in nucleotide sequence between the Moroccan vaccine strain and field isolates warranted a more in depth analysis of this epizootic. In this study, sequence analysis showed that isolates obtained from four provinces of eastern Morocco were identical, demonstrating that a single SPPV strain was responsible for the 2010 epizootic. In addition, the genome fragments sequenced and phylogenetic analyses undertaken as part of this study showed significant differences between field isolates and the Moroccan vaccine strain. New PCR methods were developed to differentiate between wild-type isolates and vaccine strains of SPPV. Using these methods, no trace of wild-type SPPV was found in the vaccine and no evidence was found to suggest that the vaccine strain was causing clinical disease.

Genetic diversity of fusion gene (ORF 117), an analogue of vaccinia virus A27L gene of capripox virus isolates

The fusion gene (ORF 117) sequences of twelve (n = 12) capripox virus isolates namely sheeppox (SPPV) and goatpox (GTPV) viruses from India were demonstrated for their genetic and phylogenetic relationship among them. All the isolates were confirmed for their identity by routine PCR before targeting ORF 117 gene for sequence analysis. The designed primers specifically amplified ORF 117 gene as 447 bp fragment from total genomic DNA extracted from all the isolates. Sequence analysis revealed a significant percentage of identity among GTPV, SPPV and between them at both nucleotide and amino acid levels. The topology of the phylogenetic tree revealed that three distinct clusters corresponding to SPPV, GTPV and lumpy skin disease virus was formed. However, SPPV Pune/08 and SPPV Roumanian Fanar isolates were clustered into GTPV group as these two isolates showed a 100 and 99.3 % identity with GTPV isolates of India at nt and aa levels, respectively. Protein secondary structure and 3D view was predicted and found that it has high antigenic index and surface probability with low hydrophobicity, and it can be targeted for expression and its evaluation to explore its diagnostic potential in epidemiological investigation in future.

TaqMan based real-time duplex PCR for simultaneous detection and quantitation of capripox and orf virus genomes in clinical samples

A rapid and sensitive TaqMan based real-time duplex PCR (drt-PCR) assay for simultaneous detection, differentiation and quantitation of Capripoxvirus (CaPV) and Orf virus (ORFV) DNA, was optimized targeting the highly conserved DNA polymerase genes of these virus genomes. Two pairs of oligonucleotide primers and two hybridization probes labeled with Cy5/BHQ1 and Hex/BHQ1 for CaPV and ORFV, respectively, were used in the drt-PCR assay. The assay was found to be specific only to targeted viruses and did not react with buffalopox virus (BPXV), camelpox virus (CMLV) (Orthopoxviruses) and cDNA of Peste des petits ruminants virus and bluetongue virus, the other common viruses of sheep and goats. The detection limit of the assay was 20 copies for each of the standard plasmid and 35fg of viral genomic DNA for CaPV and ORFV, respectively, in a single and mixed virus population. Both intra-(0.49-4.6% and 0.7-3.7%) and inter-(0.6-2.35% and 0.27-2.1%) assay variations of drt-PCR for CaPV and ORFV DNA were within the acceptable limits, implying high reproducibility and repeatability of the assay. Further, the diagnostic specificity and the sensitivity of the assay was assessed using known virus isolates of sheeppox virus (SPPV), goatpox virus (GTPV) and ORFV and the clinical specimens from sheep and goats. The developed drt-PCR assay was able to detect, differentiate, quantify simultaneously and also to identity mixed infections of CaPV and ORFV in sheep and goats.

Multiplex PCR for simultaneous detection and differentiation of sheeppox, goatpox and orf viruses from clinical samples of sheep and goats

A multiplex polymerase chain reaction (mPCR) was developed and evaluated for detection of pox viral infections simultaneously using clinical samples from sheep and goats. Specific primers for three pox viruses of sheep and goats including sheeppox virus (SPPV), goatpox virus (GTPV) and orf virus (ORFV) were designed targeting conserved sequences of the DNA binding phosphoprotein (I3L) coding gene of Capripoxvirus (CaPV) and the DNA polymerase (E9L) gene of parapoxvirus for identification of these viruses. The mPCR assay was found to be sensitive for detecting as low as 350 pg of viral genomic DNA or 10(2) copies of standard plasmid of individual targets; and 10(3) copies of plasmid in a mixture of two or three viruses. The assay was specific for detecting one or more of the viruses in various combinations from clinical specimens. Two hundred and thirty five (n=235) clinical samples from sheep and goats received from different geographical regions of the country for diagnosis of pox infection were evaluated by developed uniplex and mPCR assays. The assay had improved diagnostic sensitivity and specificity over to in-use laboratory diagnostic methods and can be useful for clinical differential diagnosis of these infections in sheep and goats.

Animal poxvirus vaccines: a comprehensive review

The family Poxviridae includes several viruses of medical and veterinary importance. Global concerted efforts combined with an intensive mass-vaccination campaign with highly efficaceious live vaccine of vaccinia virus have led to eradication of smallpox. However, orthopoxviruses affecting domestic animals continue to cause outbreaks in several endemic countries. Different kinds of vaccines starting from conventional inactivated/attenuated to recombinant protein-based vaccines have been used for control of poxvirus infections. Live virus homologous vaccines are currently in use for diseases including capripox, parapox, camelpox and fowlpox, and these vaccines are highly effective in eliciting (with the exception of parapoxviruses) long-lasting immunity. Attenuated strains of poxviruses have been exploited as vectored vaccines to deliver heterologous immunogens, many of them being licensed for use in animals. Worthy of note are vaccinia virus, fowlpox virus, capripoxvirus, parapoxvirus and canary pox, which have been successfully used for developing new-generation vaccines targeting many important pathogens. Remarkable features of these vaccines are thermostability and their ability to engender both cellular and humoral immune responses to the target pathogens. This article updates the important vaccines available for poxviruses of livestock and identifies some of the research gaps in the present context of poxvirus research.

Differentiation of sheeppox and goatpox viruses by polymerase Chain reaction-restriction fragment length polymorphism

In the present study, the partial gene sequences of P32 protein, an immunogenic envelope protein of Capripoxviruses (CaPV), were analyzed to assess the genetic relationship among sheeppox and goatpox virus isolates, and restriction enzyme specific PCR-RFLP was developed to differentiate CaPV strains. A total of six goatpox virus (GTPV) and nine sheeppox virus (SPPV) isolates of Indian origin were included in the sequence analysis of the attachment gene. The sequence analysis revealed a high degree of sequence identity among all the Indian SPPV and GTPV isolates at both nucleotide and amino acid levels. Phylogenetic analysis showed three distinct clusters of SPPV, GTPV and Lumpy skin disease virus (LSDV) isolates. Further, multiple sequence alignment revealed a unique change at G120A in all GTPV isolates resulting in the formation of Dra I restriction site in lieu of EcoR I, which is present in SPPV isolates studied. This change was unique and exploited to develop restriction enzyme specific PCR-RFLP for detection and differentiation of SPPV and GTPV strains. The optimized PCR-RFLP was validated using a total of fourteen (n=14) cell culture isolates and twenty two (n=22) known clinical samples of CaPV. The Restriction Enzyme specific PCR-RFLP to differentiate both species will allow a rapid differential diagnosis during CaPV outbreaks particularly in mixed flocks of sheep and goats and could be an adjunct/supportive tool for complete gene or virus genome sequencing methods.

Phylogenetic analysis of Chinese sheeppox and goatpox virus isolates

Background

Sheeppox virus (SPPV) and goatpox virus (GTPV), members of the Capripoxvirus genus of the Poxviridae family are causative agents of sheep pox and goat pox respectively, which are important contagious diseases and endemic in central and northern Africa, the Middle and Far East, and the Indian sub-continent. Both sheep pox and goat pox can cause wool and hide damage, and reduce the production of mutton and milk, which may result in significant economic losses and threaten the stockbreeding. In this study, three SPPVs and two GTPVs were collected from China in 2009 and 2011. We described the sequence features and phylogenetic analysis of the P32 gene, GPCR gene and RPO30 gene of the SPPVs and GTPVs to reveal their genetic relatedness.

Results

Sequence and phylogenetic analysis showed that there was a close relationship among SPPV/GanS/2/2011/China, SPPV/GanS/1/2011/China and SPPV/NingX/2009/China. They were clustered on the same SPPV clade. GTPV/HuB/2009/China and GS-V1 belonged to the GTPV lineage. GS-V1 was closely related to other GTPV vaccine strains. GTPV/HuB/2009/China and GS-V1 were clustered with GTPVs from China and some southern Asian countries.

Conclusion

This study may expand the datum for spread trend research of Chinese SPPVs and GTPVs, meanwhile provide theoretical references to improve the preventive and control strategy.

An outbreak of sheep pox associated with goat poxvirus in Gansu province of China

Three strains of Capripoxviruses (CaPVs) were isolated from an outbreak of sheep pox in Gansu province of China. They were analyzed by P32 gene-based molecular methods and a species-specific PCR based on the RPO30 gene. Two bands which are specific to goat poxvirus (GTPV) were observed after the PCR products of P32 gene were digested with the endonuclease of Hinf I. Moreover, an amplicon of 172 bp, which is specific to GTPV, was amplified from the viruses by using the RPO30 gene-based PCR. Sequence analysis of the P32 genes showed that three nucleotide bases for coding residue of aspartic acid which are located at 163-165 position of P32 gene of sheep poxvirus (SPPV) were absent, and six single nucleotide substitutions which are characteristic of GTPV were present. The viruses were genetically closer to GTPV strains and clustered into the GTPV branch of the phylogenetic tree constructed on the basis of the P32 gene. The results characterized the isolated viruses as GTPV. It is the first report of an outbreak of sheep pox associated with GTPV in China.