Cellular infiltration, cytokines, and histopathology of skin lesions associated with different clinical forms and stages of naturally occurring lumpy skin disease in cattle.

Lumpy skin disease (LSD) caused by the Capripoxvirus LSD virus which infects cattle, leading to a serious disease characterized by fever and the eruption of skin nodules all over the surface of the body. Our understanding of the pathogenesis of this disease is still incomplete, particularly the immunopathological alterations occurring in the skin nodules of infected animals. Therefore, we collected skin nodules from naturally infected cattle with different forms of the disease, both in the early stage of clinical infection and after disease progression. The skin samples were examined both histopathologically and immunohistochemically using a variety of antibodies targeting immune cellular markers and cytokines. As a result, the dermatohistopathology revealed orthokeratotic hyperkeratosis, vasculitis, epidermal microvesicles, and cellules claveleuses of Borrel in the early stage of infection, with the severity of the lesions correlating with the severity of the clinical disease. Meanwhile, late-stage samples had epidermal hyperkeratosis as well as dermal lymphocytic and histiocytic infiltrations. The predominant cellular infiltrates in the cutaneous lesions of early-stage LSD samples were interferon (IFN)-γ+ cells and CD4+ T lymphocytes with few macrophage lineage cells. However, in the late-stage samples, numerous Iba-1+ macrophages, with few IFN-γ+ cells and CD4+ T lymphocytes, were detected. Our findings indicate that IFN-γ+ cells, CD4+ T lymphocytes, and macrophages play a key role in the immunity against natural LSD virus infection and imply that cutaneous vasculopathy associated with LSD virus infection is an immune-mediated lesion. The current study contributes to our understanding of the pathogenesis of LSD.

Molecular identification and characterization of Lumpy skin disease virus emergence from cattle in the northeastern part of Thailand.

BACKGROUND: Lumpy skin disease (LSD), a disease transmitted by direct and indirect contact with infected cattle, is caused by the Lumpy skin disease virus (LSDV). The disease affects cattle herds in Africa, Europe, and Asia. The clinical signs of LSD range from mild to the appearance of nodules and lesions in the skin leading to severe symptoms that are sometimes fatal with significant livestock economic losses. OBJECTIVES: This study aimed to characterize LSDV strains in the blood of infected cattle in Thailand based on the GPCR gene and determine the phylogenetic relationship of LSDV Thailand isolates with published sequences available in the database. METHODS: In total, the blood samples of 120 cattle were collected from different farms in four provinces in the northeastern part of Thailand, and the occurrence of LSDV was examined by PCR based on the P32 antigen gene. The genetic diversity of LSDV based on the GPCR gene was analyzed. RESULTS: Polymerase chain reaction assays based on the P32 antigen gene showed that 4.17% (5/120) were positive for LSDV. All positive blood samples were amplified successfully for the GPCR gene. Phylogenetic analysis showed that LSDV Thailand isolates clustered together with LSDVs from China and Russia. CONCLUSIONS: The LSD outbreak in Thailand was confirmed, and a phylogenetic tree was constructed to infer the branching pattern of the GPCR gene from the presence of LSDV in Thailand. This is the first report on the molecular characterization of LSDV in cattle in Thailand.

A review: Lumpy skin disease and its emergence in India.

Lumpy skin disease (LSD) is a viral disease caused by lumpy skin disease virus (LSDV), a member of Capripoxvirus genus of Poxviridae family. It is a transboundary disease of the economic importance affecting cattle and water buffaloes. The disease is transmitted by arthropod vectors and causes high morbidity and low mortality. LSD has recently been reported first time in India with 7.1% morbidity among cattle. Generally, fever, anorexia, and characteristic nodules on the skin mucous membrane of mouth, nostrils, udder, genital, rectum, drop in milk production, abortion, infertility and sometimes death are the clinical manifestations of the disease. The disease is endemic in African and Middle East countries but has started spreading to Asian and other countries. It has been recently reported from China and Bangladesh sharing borders with India. We have summarized occurrence of LSD outbreaks in last 10 years in Asian countries for the first time. In India, currently epidemiological status of the disease is unknown. Vaccination along with strict quarantine measures and vector control could be effective for preventing the spread of the disease. This review aims to summarise the latest developments in the epidemiology with the focus on transboundary spread, aetiology and transmission, clinical presentations, diagnostics and management of the disease.

Minimum Infective Dose of a Lumpy Skin Disease Virus Field Strain from North Macedonia.

Infection with Lumpy Skin Disease virus (LSDV), as well as infections with other Capripox virus species, are described as the most severe pox diseases of production animals and are therefore listed as notifiable diseases under the guidelines of the World Organization for Animal Health (OIE). To our knowledge there is only a single study examining dose dependency, clinical course, viremia, virus shedding, as well as serological response following experimental LSDV "Neethling" inoculation. Here, we inoculated cattle with four different doses of LSDV strain "Macedonia2016", a recently characterized virulent LSDV field strain, and examined clinical symptoms, viremia, viral shedding, and seroconversion. Interestingly, around 400 cell culture infectious dose50 (CCID50) of LSDV-"Macedonia2016" were sufficient to induce generalized Lumpy Skin Disease (LSD) in two out of six cattle but with a different incubation time, whereas the other animals of this group showed only a mild course of LSD. However, differences in incubation time, viral loads, serology, and in the clinical scoring could not be observed in the other three groups. In summary, we concluded that experimental LSDV infection of cattle with an infectious virus titer of 105 to 106 CCID50/mL of "Macedonia2016" provides a robust and sufficient challenge model for future studies.

Lumpy Skin Disease Is Characterized by Severe Multifocal Dermatitis With Necrotizing Fibrinoid Vasculitis Following Experimental Infection.

Lumpy skin disease is a high-consequence disease in cattle caused by infection with the poxvirus lumpy skin disease virus (LSDV). The virus is endemic in most countries in Africa and an emerging threat to cattle populations in Europe and Asia. As LSDV spreads into new regions, it is important that signs of disease are recognized promptly by animal caregivers. This study describes the gross, microscopic, and ultrastructural changes that occur over time in cattle experimentally challenged with LSDV. Four calves were inoculated with wildtype LSDV and monitored for 19 to 21 days. At 7 days after inoculation, 2 of the 4 cattle developed multifocal cutaneous nodules characteristic of LSD. Some lesions displayed a targetoid appearance. Histologically, intercellular and intracellular edema was present in the epidermis of some nodules. Occasional intracytoplasmic inclusion bodies were identified in keratinocytes. More severe and consistent changes were present in the dermis, with marked histiocytic inflammation and necrotizing fibrinoid vasculitis of dermal vessels, particularly the deep dermal plexus. Chronic lesions consisted of full-thickness necrosis of the dermis and epidermis. Lesions in other body organs were not a major feature of LSD in this study, highlighting the strong cutaneous tropism of this virus. Immunohistochemistry and electron microscopy identified LSDV-infected histiocytes and fibroblasts in the skin nodules of affected cattle. This study highlights the noteworthy lesions of LSDV and how they develop over time.

Determination of lumpy skin disease virus in bovine meat and offal products following experimental infection.

Lumpy skin disease (LSD) has recently expanded its range northwards to include the Balkans, Turkey and Russia. Because there was no solid evidence conclusively verifying the transmission mechanism in the field and LSDV viraemic animals with overt and asymptomatic presentation of disease and their products may represent a risk as an indirect transmission pathway. In this work, we used PCR positivity and infectivity in clinical and subclinical infection to evaluate the safety of meat and offal products from cows infected with the virulent LSDV strain Russia/Dagestan/2015. At day 21 post infection, seven of the 12 animals developed the generalized disease, and four animals became subclinically infected without apparent clinical signs. Upon examination and necropsy, the animals with the generalized disease had skin lesions; noticeably enlarged lymph nodes; and lesions in the lungs, trachea and testicles; whereas subclinically ill animals exhibited only enlarged lymph nodes and fever. For both disease presentations, testing of skeletal meat by PCR and virus isolation showed that the skeletal meat did not contain live virus or viral genome, whereas in cattle with generalized disease, meat with gross pathology physically connected under the site of a skin lesion was positive for the live virus. In subclinical infection, only enlarged lymph nodes carried the infectious virus, while the other internal organs tested in both types of disease manifestation were negative except for the testicles. Overall, our findings demonstrate that clinically and subclinically infected animals are reservoirs of live LSDV in lymph nodes and testicles, whereas deep skeletal meat in both types of infection do not carry live virus and the risk of transmission through this product seems very low. The detection of LSDV in testicular tissues in subclinically ill animals is concerning because of the potential to spread infection through contaminated semen. This aspect requires reconsideration of surveillance programmes to identify these Trojan horses of LSDV infection.

Analysis and insights into recombination signals in lumpy skin disease virus recovered in the field.

Wide spread incidences of vaccine-like strains of lumpy skin disease virus (LSDV) have recently been reported in a Russian region with a neighboring country that actively vaccinate with a live attenuated LSD vaccine. The use of live-attenuated viruses (LAVs) as vaccines during an active outbreak, creates potential ground for coinfection of hosts and emergence of a strain combining genetic fragments of both parental vaccine and field strains. In this study, we analyse the vaccine-like strain LSDV RUSSIA/Saratov/2017 detected in Saratovskaya oblast, a region sharing border with Kazakhstan. To gain insight into possible recombination signals, a full-genome next-generation sequencing of the viral genome was performed using the Illumina platform. The genome contains the backbone of a live-attenuated vaccine with a patchwork of wild-type field virus DNA fragments located throughout. A total of 27 recombination events were identified. The average distance between the recombination sites was 3400 base pairs (bp). The impact of the recombination events on the virulence and transmission capacity of the identified virus remains to be clarified. These findings provide evidence for the first time of genetic exchanges between closely related strains of capripoxviruses in the field and a vaccine strain, and prompt a revisiting of the vaccination issue for a safe and efficacious prevention and control strategy of LSD.

Risk of introduction of lumpy skin disease in France by the import of vectors in animal trucks.

BACKGROUND: The lumpy skin disease virus (LSDV) is a dsDNA virus belonging to the Poxviridae family and the Capripoxvirus genus. Lumpy skin diseases (LSD) is a highly contagious transboundary disease in cattle producing major economic losses. In 2014, the disease was first reported in the European Union (in Cyprus); it was then reported in 2015 (in Greece) and has spread through different Balkan countries in 2016. Indirect vector transmission is predominant at small distances, but transmission between distant herds and between countries usually occurs through movements of infected cattle or through vectors found mainly in animal trucks. METHODS AND PRINCIPAL FINDINGS: In order to estimate the threat for France due to the introduction of vectors found in animal trucks (cattle or horses) from at-risk countries (Balkans and neighbours), a quantitative import risk analysis (QIRA) model was developed according to the international standard. Using stochastic QIRA modelling and combining experimental/field data and expert opinion, the yearly risk of LSDV being introduced by stable flies (Stomoxys calcitrans), that travel in trucks transporting animals was between 6 x 10-5 and 5.93 x 10-3 with a median value of 89.9 x 10-5; it was mainly due to the risk related to insects entering farms in France from vehicles transporting cattle from the at-risk area. The risk related to the transport of cattle going to slaughterhouses or the transport of horses was much lower (between 2 x 10-7 and 3.73 x 10-5 and between 5 x 10-10 and 3.95 x 10-8 for cattle and horses, respectively). The disinsectisation of trucks transporting live animals was important to reduce this risk. CONCLUSION AND SIGNIFICANCE: The development of a stochastic QIRA made it possible to quantify the risk of LSD being introduced in France through the import of vectors that travel in trucks transporting animals. This tool is of prime importance because the LSD situation in the Balkans is continuously changing. Indeed, this model can be updated to process new information on vectors and the changing health situation, in addition to new data from the TRAde Control and Expert System (TRACES, EU database). This model is easy to adapt to different countries and to other vectors and diseases.

Molecular characterization of lumpy skin disease virus in Namibia, 2017.

Between January and July 2017, lumpy skin disease (LSD) outbreaks were reported in cattle in Namibia. DNA was extracted from skin biopsies taken from 32 cattle, and the RNA polymerase 30 kDa subunit (RPO30) gene of the LSD virus (LSDV) was successfully amplified by PCR. Phylogenetic analysis revealed that the newly sequenced LSDV isolates from Namibia were identical to LSDV isolates identified previously in Burkina Faso, Egypt, Greece, Niger, Serbia and South Africa. Given that only unvaccinated herds were affected by LSD, it is recommended that the current vaccination programmes in Namibia be re-evaluated to allow nationwide coverage.

Clinical, hematologic, and biochemical findings in cattle infected with lumpy skin disease during an outbreak in southwest Iran.

This study was performed to determine the clinical, hematologic, and biochemical findings in animals affected with lumpy skin disease (LSD) in southwest Iran. Sixty cattle with LSD were included in this study and compared with 20 healthy ones as the control group. The disease was diagnosed based on clinical examination and confirmed by polymerase chain reaction analysis of the blood samples. The major observed clinical signs included skin nodules, fever, enlarged lymph nodes, and edema. In hematologic assessment, the average numbers of leukocytes, lymphocytes, eosinophils, erythrocytes, and platelets, as well as the average level of hemoglobin in the infected animals were significantly lower than in the control group. Biochemical experiments showed that the serum glucose, total and direct bilirubin, aspartate aminotransferase, and creatine phosphokinase activities in the infected group were significantly elevated. LSD also caused a significant reduction in the levels of serum creatinine, albumin, and iron. In total, LSD was associated with an overall decline in different blood cell types and significant changes in serum biochemical profile. These alterations could be related to the inflammatory disease processes and injuries in various organs, especially the liver. Hematologic and biochemical profiles can be utilized to better understand different aspects of LSD pathogenesis and ultimately improve its prognostic, management, and treatment methods.

Epidemiological Study of Lumpy Skin Disease Outbreaks in North-western Iran.

Lumpy skin disease (LSD) is a highly contagious transboundary disease of cattle with major economic losses. This study was undertaken to address the emergence and epidemiological features of LSD in four north-western provinces of Iran. These provinces have extensive borders with others country including Iraq, Turkey, Azerbaijan and Armenia. A population of 683 cattle from 91 farms were examined during LSD outbreak in Iran during 2014-2016. The information of the farms including the population size, gender, age, vaccination status, clinical signs and the number of death because of LSD were recorded in the designed questionnaires. A number of 234 blood samples were collected randomly from animals with and without clinical signs of LSD. DNA was extracted from blood samples, and they were used for amplifying a fragment of 434 bp in size coupled with restriction fragment length polymorphism (RFLP) for molecular detection of lumpy skin disease virus (LSDV). The estimated prevalence, cumulative mortality and case fatality were 17.9%, 3.5% and 19.7%, respectively. There was no significant difference in occurrence of the disease between male and female cattle. LSD occurrence in age groups above 5 years old and below 6 months old showed highest and lowest relative frequencies, respectively. Vaccination was significantly decreased the occurrence of clinical disease. The developed PCR-RFLP technique was able to differentiate between LSDV, sheep pox virus (ShPV) and goat pox virus (GPV). It was concluded that LSD was entered into Iran probably from Iraq via uncontrolled animal movements along common land borders between two countries. Developed PCR-RFLP could be used as a rapid and inexpensive method for differentiating Capripoxviruses (CaPVs).

Hematological and serum biochemical findings in clinical cases of cattle naturally infected with lumpy skin disease.

INTRODUCTION: Lumpy skin disease (LSD) is an acute viral disease of cattle that is currently emerging in the Middle East region and poses a serious threat to Europe and the rest of the world. The objective of this study was to describe hematological and serum biochemical findings associated with natural clinical infection of LSD in cattle. METHODOLOGY: A total of 129 animals clinically infected with LSD were enrolled in the study. Venous blood sample were collected from study animals, and hematological and serum biochemical parameters were measured. RESULTS: Leukocytopenia was found in 8.7%, while leucocytosis was found in 18.2% of affected cattle. Decreased hematocrit concentration was seen in 18.3%. Most affected cattle had reduced mean corpuscular volume (43.7%), mean corpuscular hemoglobin (14.3%), and mean corpuscular hemoglobin concentration (11.5%). All cattle with abnormal platelets count had thrombocytopenia. Hyperfibrinogenemia, hyperproteinemia, and hyperalbuminemia were found in 69%, 59.6%, and 37.2% of affected cattle, respectively. Decreased creatinine concentration was seen in 65.8%. Hyperkalemia and hyperchloremia was found in 9.6% and 10.4% of the affected cattle, respectively. CONCLUSIONS: LSD appears to be associated with inflammatory leukogram, anemia, thrombocytopenia, hyperfibrinogenemia, hyperproteinemia, decreased creatinine concentration, hyperchloramia, and hyperkalemia. These are likely due to the associated severe inflammatory process and disease complications such as anorexia and reduced muscle mass. This is the first study that documents hematological and serum biochemical findings associated with LSD infection. Understanding the blood profile picture may give further insight to the pathogenesis of the disease and help in treatment of individual cattle.

Lumpy skin disease of cattle: an emerging problem in the Sultanate of Oman.

Lumpy skin disease (LSD) is a highly infectious disease of cattle caused by a virus belonging to the Capripoxvirus genus of the family Poxviridae. The purpose of this study is to place on record the first confirmation of LSD in the Sultanate. The disease was diagnosed and confirmed using polymerase chain reaction, histopathology, transmission electron microscopy and serum neutralization testing. The epizootic occurred in 2009 involving a large number of animals and covering a wide area including Nezwa, Alqabel, Sohar, Saham and Burimi. Morbidity and mortality rates of 29.7 and 26.3 %, and 13.6 and 15.4 % were observed at Nezwa and Sohar, respectively. The clinical signs were much more severe in Holstein-Friesian cattle compared to indigenous breeds and were characterized by multiple skin nodules covering the neck, back, perineum, tail, limbs and genital organs. Affected animals also exhibited lameness, emaciation and cessation of milk production. Oedema of limbs and brisket, and superficial lymph node enlargement were highly prominent. It is not known from where the virus originated, or how it spread to the Sultanate. The disease has become endemic in the country and is liable to extend to other Gulf Cooperation Council Countries and cause a pandemic. It is of major concern to the Omani dairy industry. Due to the widespread presence of screw worm, serious economic losses can follow outbreaks.

Seminal transmission of lumpy skin disease virus in heifers.

It is known that lumpy skin disease virus (LSDV) can be shed in bull semen following infection and also that artificial insemination (AI) poses a biosecurity risk. However, it is not known whether the use of LSDV infected semen in AI poses a biosecurity risk. The aim of this study was to investigate whether LSDV, transmitted through semen, can infect cows and their embryos. Two controlled trials were performed simultaneously. Eleven young beef heifers, naïve to LSDV, were synchronized using an OvSynch protocol and inseminated on Day 0 with fresh semen spiked with a field strain of LSDV on day 0. Six of the heifers were superovulated on Day 1 using pregnant mare serum gonadotropin, and embryos were flushed from these heifers on Day 6. Blood and serum samples were collected from Day 4 until Day 27 to determine the presence of LSDV by PCR and virus isolation, and the presence of antibodies against LSDV by SNT. The first clinical signs of LSD were noticed on Day 10, followed by severe generalized LSD in three heifers and mild LSD in two more heifers. Two heifers were humanely euthanized due to severe unresponsive stranguria. LSDV was detected by PCR, virus isolation or electron microscopy in blood, embryos and organs of experimentally infected animals; and eight heifers had seroconverted by Day 27. Two control animals were not affected. This is the first report of experimental seminal transmission of LSDV in cattle.

Quantification of lumpy skin disease virus following experimental infection in cattle.

Lumpy skin disease along with sheep pox and goatpox are the most serious poxvirus diseases of livestock, and are caused by viruses that belong to the genus Capripoxvirus within the subfamily Chordopoxvirinae, family Poxviridae. To facilitate the study of lumpy skin disease pathogenesis, we inoculated eight 4- to 6-month-old Holstein calves intravenously with lumpy skin disease virus (LSDV) and collected samples over a period of 42 days for analysis by virus isolation, real-time PCR and light microscopy. Following inoculation, cattle developed fever and skin nodules, with the extent of infection varying between animals. Skin nodules remained visible until the end of the experiment on day post-inoculation (DPI) 42. Viremia measured by real-time PCR and virus isolation was not observed in all animals but was detectable between 6 and 15 DPI. Low levels of viral shedding were observed in oral and nasal secretions between 12 and 18 DPI. Several tissues were assessed for the presence of virus at DPI 3, 6, 9, 12, 15, 18 and 42 by virus isolation and real-time PCR. Virus was consistently detected by real-time PCR and virus isolation at high levels in skin nodules indicating LSDV has a tropism for skin. In contrast, relatively few lesions were observed systemically. Viral DNA was detected by real-time PCR in skin lesions collected on DPI 42. Cattle developing anti-capripoxvirus antibodies starting at DPI 21 was detected by serum neutralization. The disease in this study varied from mild with few secondary skin nodules to generalized infection of varying severity, and was characterized by morbidity with no mortality.

The detection of lumpy skin disease virus in samples of experimentally infected cattle using different diagnostic techniques.

Lumpy skin disease (LSD) is a disease of cattle, primarily in Africa and Madagascar and rarely in the Middle East. It is caused by a capripoxvirus that belongs to the family Poxviridae. The disease is of economic importance in endemic areas. Effective control of LSD requires accurate and rapid laboratory techniques to confirm a tentative clinical diagnosis. Comparative studies on different diagnostic tests used at different stages of the disease have not been done. The aim of this study was to compare several of these tests. Six seronegative bulls, between 11 and 20 months of age, were infected intravenously and kept in an insect-free facility. The course of the infection was monitored. During a 3-month period blood samples and skin biopsies were collected for virus isolation and polymerase chain reaction (PCR). Skin biopsies were also examined using transmission electron microscopy (TEM). The incubation period in infected animals varied from 4-5 days. The length of the viraemic period did not correlate with the severity of clinical disease. Viraemia was detected from 1-12 days using virus isolation and from 4-11 days using the PCR, which is longer than has previously been reported. Virus was isolated from skin biopsies until Day 39 post infection (p.i.) and PCR could demonstrate viral DNA until Day 92 p.i. Transmission electron microscopy of negatively stained skin biopsies detected LSD virus only in one of the four bulls that developed skin lesions until Day 33 p.i. The PCR was a fast and sensitive method to demonstrate viral DNA in blood and skin samples. It could detect viral nucleic acid in skin lesions 53 days longer than virus isolation. Virus isolation from blood and skin samples was sensitive and reliable, but as a single test it may be too time-consuming to use although this depends on how rapidly the diagnosis must be confirmed. In conclusion, this study showed the PCR to be superior in detecting LSD virus from blood and skin samples. However, virus isolation is still required when the infectivity of the LSD virus is to be determined.

An investigation of possible routes of transmission of lumpy skin disease virus (Neethling).

British cattle were infected with the South African (Neethling) strain of lumpy skin disease virus (LSDV) and their clinical signs monitored over a 3-week period. Different routes of infection were assessed for effect on the clinical characteristics of the disease by using a clinical scoring system. Neither of 2 animals inoculated onto the conjunctival sac showed clinical signs of seroconverted. The intradermal route produced local lesions in 21 of 25 animals, and generalized infection in 4. In contrast the intravenous route produced generalized lesions in 8 of 11 animals. Seven uninfected animals were housed in contact with infected animals for 1 month. None developed clinical signs or produced detectable serum neutralizing antibodies. Six of seven of these animals were then challenged and were fully susceptible to infection. The results suggest that the transmission of LSDV between animals by contagion is extremely inefficient, and that parenteral inoculation of virus is required to establish infection. The high proportion of animals with generalized disease following intravenous inoculation implies that naturally occurring cases of generalized LSD may follow spread by intravenously feeding arthropods.

Adverse reactions in cattle to a capripox vaccine.

Capripox vaccine (strain 0240) caused severe generalised skin reactions in vaccinated dairy cattle in two herds, whereas beef cattle did not develop reactions. All the reacting animals developed lumpy skin disease-like lesions. The incidence of skin lesions in first-lactation cows in herd A was 22.9 per cent and in herd B 29.3 per cent, mainly in the post-calving period. In older cows, the incidence was 10 per cent in herd A and 12.4 per cent in herd B. In herd B the high-yielding lactating cows were the most severely affected. There was a decrease of 3.5 per cent in milk production in each herd over a period of 12 days, and six first calving animals (3.5 per cent) and six cows (1.5 per cent) were slaughtered. A capripox virus was isolated from the animals with severe lesions, and was also demonstrated by electron microscopy. The histopathological lesions were similar to those of lumpy skin disease. The extent of the lesions appeared to be stress-related and, to a lesser degree, correlated with age and breed.

Capripoxvirus disease in an Arabian oryx (Oryx leucoryx) from Saudi Arabia.

Lumpy skin disease caused by a capripoxvirus was observed in a captive-bred female Arabian oryx (Oryx leucoryx) at the National Wildlife Research Center, Taif, Saudi Arabia. Clinical signs included severe general depression with fever, anorexia, greater than 1,000 nodular cutaneous lesions and gradual recovery over 2 mo. The virus was found by electron microscopy and paired sera showed an increasing virus neutralization antibody titer against capripoxvirus. A serologic survey of the herd of 90 oryx showed a low prevalence (2%) of this infection. This report describes the first case of lumpy skin disease in an Arabian oryx.