Lumpy Skin Disease Outbreaks Research Articles

Lumpy skin disease outbreak and quarantine in the Incheon area

Lumpy skin disease outbreak and quarantine in the Incheon area

Epidemiology, genetic characterization and population structure analysis of lumpy skin disease virus from North India.

Lumpy skin disease (LSD) is a transboundary, viral disease of cattle with a significant economic impact on the livestock industry. This study describes the epidemiological investigations of outbreaks of LSD that occurred in 2022 in three Indian states viz., Haryana, Himachal Pradesh and Rajasthan and the genetic characterization of Lumpy skin disease viruses (LSDVs). Also, the population structure analysis of LSDVs was carried out. Out of 138 scab samples tested from suspected cattle for LSDV, 106 were found positive. Of these, nine representative scab samples were further genetically characterized. Phylogenetic analysis based on the P32 and EEV gene sequences depicted that the LSDV strains of the present study had nucleotide identity of 100% and 99.10-99.45%, respectively with the LSDV/2019 field strains of India. Multiple sequence alignment of the EEV glycoprotein gene sequences revealed nucleotide polymorphisms at three positions viz., G178A, G253A and A459G in circulating LSDV/2022 field strains. Based on the median joining network analysis of the EEV gene, 12 haplotypes were identified among the LSDV populations. Population structure analysis corresponding to the EEV gene revealed high haplotype (0.8486 ± 0.026) and low nucleotide diversities (0.00636 ± 0.0006) and negative values for neutrality indices, indicating a high number of closely related haplotypes and the studied population may have undergone a recent expansion. The findings will help in understanding the distribution and dynamics of LSDV populations, which will prove pivotal in designing and implementing effective management and control strategies.

A systematic review of epidemiological modelling in response to lumpy skin disease outbreaks.

Lumpy skin disease (LSD) is an infectious disease currently spreading worldwide and poses a serious global threat. However, there is limited evidence and understanding to support the use of models to inform decision-making in LSD outbreak responses. This review aimed to identify modelling approaches that can be used before and during an outbreak of LSD, examining their characteristics and priorities, and proposing a structured workflow. We conducted a systematic review and identified 60 relevant publications on LSD outbreak modelling. The review identified six categories of question to be addressed following outbreak detection (origin, entry pathway, outbreak severity, risk factors, spread, and effectiveness of control measures), and five analytical techniques used to address them (descriptive epidemiology, risk factor analysis, spatiotemporal analysis, dynamic transmission modelling, and simulation modelling). We evaluated the questions each analytical technique can address, along with their data requirements and limitations, and accordingly assigned priorities to the modelling. Based on this, we propose a structured workflow for modelling during an LSD outbreak. Additionally, we emphasise the importance of pre-outbreak preparation and continuous updating of modelling post-outbreak for effective decision-making. This study also discusses the inherent limitations and uncertainties in the identified modelling approaches. To support this workflow, high-quality data must be collected in standardised formats, and efforts should be made to reduce inherent uncertainties of the models. The suggested modelling workflow can be used as a process to support rapid response for countries facing their first LSD occurrence and can be adapted to other transboundary diseases.

Lumpy skin disease virus isolation, experimental infection, and evaluation of disease development in a calf

Lumpy skin disease (LSD) is one of the most economically significant viral diseases of cattle caused by the Lumpy Skin Disease Virus (LSDV), classified as a member of the genus Capripoxvirus and belongs to the family Poxviridae. Nodular skin samples were collected from clinically sick cattle in the districts of Amuru and Wara Jarso Ethiopia to isolate LSD virus. The virus was isolated using primary lamb testis and kidney cells. The isolated LSDV was infected into a healthy calf while maintaining the necessary biosecurity measures to generate skin lesions and to assess disease progression using postmortem examinations. On the fourth day after virus inoculation, the calf developed typical LSD skin nodules with increased rectal temperature, which lasted until the 12th day, when they began to decrease. Viral shedding was detected in nasal, oral, and conjunctival swabs from 6 to 14 days after infection using real-time PCR. Post-mortem tissue specimens tested positive for LSD virus using real-time PCR and virus isolation. This study showed that LSDV were responsible for the LSD outbreaks, and the appearance of typical skin nodules accompanied by fever (> 39.5 °C) defined the virus’s virulent status. The experimental infection with the isolated infectious LSDV could serve as a platform for future vaccine evaluation study using an LSDV challenge model.

Spatiotemporal Analysis of Lumpy Skin Disease in Türkiye (2013-2021)

Abstract Lumpy skin disease (LSD) is a serious, transboundary disease that affects cattle all over the world and results in considerable productivity losses. Although Türkiye’s first outbreak of LSD was reported in August 2013, there is very little information available about the outbreak’s spatiotemporal distribution or severity. GIS-based data analysis provides crucial tools for describing the spatial epidemiology of the disease by assessing the spatial distribution of LSD across time. This study used information on outbreaks reported to the the World Animal Health Organization (WOAH-OIE) between 2013 and 2021 to conduct a retrospective study on the epidemiology of LSD in Türkiye. Differences in the number of reported outbreaks and cases across different regions, provinces, months, and years were evaluated and descriptive statistics were calculated. In addition, spatial statistical tests (Local Moran’s I and Getis-Ord Gi*) and Geographical Information Systems (GIS) were used to assess LSD outbreaks that had taken place at the province level in Türkiye. Possible epidemiological clusters of LSD were identified. A total of 1787 outbreaks and 10109 cases of LSD were reported from 75 out of 81 provinces of Türkiye during the course of the nine-year period. Hotspots for the circulation of LSD were identified in the Aegean, Southeastern and Eastern regions using spatial cluster analyses and it was observed that the spatial autocorrelation of LSD cases is positive across the country. The findings from this study, it may help us comprehend the disease’s spatial character and offer authorities the beneficial information for surveillance efforts.

Using EPIWATCH® open-source surveillance to describe the epidemiology of lumpy skin disease outbreaks in South and Southeast Asia (2022-2023).

Lumpy skin disease (LSD) poses a significant threat to animal welfare and leads to economic losses in affected countries. LSD outbreaks may also impact trade and regional relationships. South and Southeast Asia, with its dense livestock population and intricate trade networks, are susceptible to LSD outbreaks. Indonesia confirmed its first LSD cases in March 2022, leading to substantial livestock losses by August 2023. Australia, an important player in the global beef industry, faced trade disruptions due to LSD concerns raised by Indonesia and Malaysia, claims that were refuted by Australian authorities. The dispute highlights the need for good surveillance. EPIWATCH®, employing artificial intelligence, provides real-time outbreak signals, and spatial analysis can identify LSD hotspots, leading to timely interventions. This study uses data collected by the EPIWATCH® open-source disease surveillance system at the University of New South Wales in 2022 and 2023 and compares it for timeliness and completeness with data available on the World Animal Health Information System (WAHIS). We found more timely reports of LSD outbreaks in EPIWATCH® compared to WAHIS. In conclusion, open-source surveillance tools like EPIWATCH® can provide timely alerts of disease emergence, such as LSD outbreaks in South and Southeast Asia, which can supplement formal reporting systems.

Comparative Evaluation of Different Antivirals against Lumpy Skin Disease in Cattle

India is facing a new wave of Lumpy skin disease outbreaks since May 2022, spreading in more than 22 states and causing morbidity to more than 29 lakh animals and mortality to more than 2 lakh animals. Lack of specific antiviral treatment restores symptomatic therapeutic interventions. However, in the advent of large no. of cases and severity of disease, investigations on specific antiviral drugs are imperative. This scientific study was conducted on a group of LSD-affected cattle (N = 40) from the trans-Himalayan region of Kashmir (Jammu and Kashmir). The affected cattle were subjected to different treatments, including acyclovir (n = 27), symptomatic treatment (n = 7), and ivermectin (n = 6), along with supportive drugs. The animals were carefully monitored and compared both within and between groups at various intervals (0-96 hr) using a two-way analysis of variance (ANOVA). Significant (P ≤ 0.05) improvement in regaining rectal temperature, respiration rate, and heart rate was noted 48 hours after treatment in a group of LSD-affected animals (N = 27) treated with acyclovir at a dose rate of 1 mg/kg body weight (small cattle) to 1.5 mg/kg (large cattle) intravenously in 500 ml normal saline along with supportive drugs including enrofloxacin (2.5 mg/kg), combination of meloxicam (0.25 mg/kg) and paracetamol (7.5 mg/kg) and pheniramine maleate (0.5 mg/kg) all intramuscularly, compared to group of LSD affected cattle (N = 6) treated with ivermectin (0.2 mg/kg subcutaneously) and supportive drugs and another group of LSD affected cattle (N = 7) treated symptomatically with only supportive drugs. Acyclovir treated group showed a significant (P ≤ 0.05) decrease in total leucocyte count, lymphocyte, and basophil count from 0 hour to 96 hour of treatment (23.00 ± 0.534 to 5.59 ± 0.208; 13.97 ± 0.310 to 3.43 ± 0.126; 0.11 ± 0.003 to 0.03 ± 0.001 respectively). Significant (P ≤ 0.05) decrease in total oxidative status (TOS: 73.31%) and increase in total antioxidant status (TAS: 59.9%) was observed in acyclovir treated group followed by ivermectin treated group (TOS: 68.05% and TAS: 27.16%) compared to symptomatically treated group (TOS: 42.41% and TAS: 18.75%). Acyclovir being comparatively more specific antiviral agent than ivermectin may have helped in amelioration of clinical severity and regaining of normal physiological, hematological, and oxidative indices in LSD-affected animals. The current study demonstrates expedited recovery, diminished clinical severity, and re-establishment of physiological, hematological and oxidative markers in animals subjected to acyclovir treatment, followed by animals administered with ivermectin, when compared to animals receiving symptomatic treatment. However, further studies are required to investigate safety or adverse effects, if any.

The first outbreak of Lumpy Skin Disease in Indonesia.

This study describes the first outbreak of Lumpy Skin Disease (LSD) in cattle in the Bengkalis region, Indonesia, and vaccination to control the epidemic. Data on the outbreak and vaccination was obtained from the local veterinary authority of the Bengkalis region, Indonesia. Climatological data was provided by the Meteorological, Climatological, and Geophysical Agency of Riau Province. Over the 5.5 months, the outbreak caused 10.4% (94/906) morbidity and 0.6% (6/906) mortality of cattle on infected farms. Temporally, three epidemic waves occurred during the outbreak period. Villages with cattle populations of > 150 animals (n = 36) were 5.3 times more likely to be infected with LSD compared to villages with smaller cattle populations (n = 107) (CI: 2.56-10.90, P < 0.01). The vaccination campaign covered 43.8% of cattle in villages within a 10km radius of the cases. However, vaccination in villages with larger cattle populations (n = 29) was 0.63 less likely to cover 50% of the cattle populations compared to villages with smaller cattle populations (n = 41) (CI: 0.39-1.02, P = 0.05). By the time the first two and the major waves ceased, vaccination had covered only 0.0% (n = 6036), 27.8% (n = 6,036) and 9.7% (n = 5,697) of the cattle in the 10km radius of the respective spatial clusters. The outbreak was statistically associated with rainfall and its interaction with temperature (F(2, 13) = 5.822, R2 = 0.47, P = 0.016). This study indicates that the LSD outbreak had low morbidity and mortality. Despite the low vaccination rate, the outbreak ceased, possibly due to plummeting of the abundance of insect vectors.

Evaluation of the immune responses in buffaloes vaccinated with a live-attenuated lumpy skin disease vaccine (Lumpi-ProVacInd).

Since 2019, Lumpy skin disease (LSD) has suddenly spread in many Asian countries, including India. LSD primarily occurs in cattle. However, recent LSD outbreaks in India have also revealed significant morbidity and production losses in buffaloes. This has raised concerns about the role of buffaloes in the epidemiology and transmission of LSD and necessitates the inclusion of buffaloes in the mass vaccination program for the prevention and control of the disease in the country. However, there is no significant data on the immune response in buffaloes following vaccination with the LSD vaccine. In this study, we evaluated antibody- and cell-mediated immune responses following vaccination with a newly developed live-attenuated LSD vaccine (Lumpi-ProVacInd). The detectable amount of anti-LSDV antibodies was observed at 1-2months following vaccination, with a peak antibody titer at 3months. Upon stimulation of the peripheral blood mononuclear cells (PBMCs) with the UV-inactivated LSDV antigen, there was a significant increase in CD8 + T cell counts in vaccinated animals as compared to the unvaccinated animals. Besides, vaccinated animals also showed a significant increase in IFN-γ levels upon antigenic stimulation of their PBMCs with LSDV antigen. In conclusion, the buffaloes also mount a potent antibody- and cell-mediated immune response following vaccination with Lumpi-ProVacInd.

Geospatial Analysis of Lumpy Skin Disease Outbreaks among Cattle in Uttar Pradesh, India, 2021-2022.

The emergence of lumpy skin disease (LSD) among cattle in India is concerning. District-level data on LSD cases in Uttar Pradesh between 2021 and 2022 were analyzed. A stepwise spatial analytical approach was followed by first constructing yearly and monthly disease maps for LSD incidence rates (IRs), then spatially interpolating the LSD IRs, followed by evaluating the global and local clustering of LSD IRs and finally conducting spatial regression modeling. Overall, 5784 LSD cases from 6 districts and 112,226 cases from 33 districts were detected in 2021 and 2022, respectively. In the incremental spatial autocorrelation analysis, the highest global clustering of LSD IRs for the 2022 outbreak was detected at 196.49 km. For the 2021 LSD outbreak, one district with high-low and nine districts with low-high LSD IRs were identified in the eastern region of the state. For the 2022 LSD outbreak, 13 districts with high-high and 7 districts with low-high LSD IRs were identified in the western part of the state. A geographically weighted regression model identified the impact of climate (temperature and humidity) and land cover (pasture, fallow, and non-agricultural land) on LSD IRs. The study results can aid animal health authorities in developing LSD prevention and control programs.

Evaluation of longitudinal passive immunity transfer against lumpy skin disease virus in calves by different serological methods

To implement effective lumpy skin disease (LSD) control measures, such as timely vaccination, particularly in calves and serological monitoring, it is necessary to evaluate immune response after vaccination, both in adult cattle and in their calves. The aim of this study was to evaluate passive immunity transfer and duration of maternal antibodies against lumpy skin disease virus (LSDV) in calves born to vaccinated cows by two different serological methods. The longitudinal study was carried out on two farms in Serbia where no cases were reported during LSD outbreak in 2016. Fifteen cows on each farm were vaccinated and revaccinated with attenuated vaccine - Neethling strain. A total of 30 cows and 30 calves on both farms were included in the study. Serum samples from cows were collected on calving day and serum samples from their respective calves on days 10, 20, 30, 45, 60, 75, 90, 105 and 120 after birth. Colostrum samples were collected only from 15 cows on one farm. In order to determine the presence of antibodies against LSDV a total of 30 cow sera samples, 15 colostrum samples and 270 calf sera samples were examined by commercial enzyme-linked immunosorbent assay (ELISA) and modified virus neutralization test (VNT). Overall, the performance of both serological tests was very satisfactory. The results of this longitudinal study showed that persistence of passive immunity in calves is less than 4 months, and that most calves are not protected against LSDV at that age. Since the vaccination is the most important control measure against LSDV, the recommended age of six months for vaccination of calves born to vaccinated cows should be reassessed to achieve the most optimal protection against LSD.

Epidemiology and risk factors of lumpy skin disease outbreak in cattle in the north-west area of Bangladesh

Lumpy skin disease (LSD) is an acute viral disease of cattle that recently emerged in Bangladesh that negatively impacts livestock by reducing animal production, increasing management costs, and death of infected animals. Recently, Bangladesh has faced the ominous effects of LSD, like other countries. Because of this pressing concern, the present cross-sectional study was undertaken to determine the infection status and risk factors of LSD outbreaks from January to December 2023 in Bangladesh’s northwest area. A total of 2858 cattle from various randomly selected farms were surveyed. The diagnosis was made on the basis of clinical inspection, clinical history, and owner complaints. The overall attack rate, mortality, and case fatality were 37.6%, 2.8%, and 7.5%, respectively, but in calves (≤1 month), the attack rate, mortality, and case fatality were 44.3%, 9.3%, and 21.3%, respectively. The infection status was discussed based on age, sex, breed, genotype, health status, immune status, coat color, farm size, farming system, separation of affected animals, separation place, use of common utensils, introduction of new cattle, use of vaccine and season of the year. Among them, age, sex, breed, health status, coat color, farm size, farming system, use of common utensils, and introduction of new cattle have no significant relationship with LSD outbreaks, but in calves (≤ 1 year), age has a significant association with the occurrence of LSD. The risk factor analysis revealed that the outbreaks of LSD were significantly (p&lt;0.05) associated with genotypes, immune status, separation place, vaccination status of farm, and season of the year. The findings of the present study could provide useful epidemiological data on risk factors associated with LSD to livestock owners, field veterinarians, and government-level livestock regulators, which will help formulate prevention and control strategies and minimize the negative impact of LSD on cattle farming.

Characterization, histopathology and immunogenicity of the lumpy skin disease virus isolated during 2019-20 in Bangladesh.

Lumpy skin disease (LSD) is a highly contagious vector-borne viral disease of cattle. LSD has emerged in Bangladesh in 2019, causing significant economic losses due to its high morbidity and mortality. This research was designed to isolate, identify, and assess the immunogenicity of LSD virus (LSDV) using nodular tissue samples obtained from affected cattle during the 2019-20 outbreak across nine districts of Bangladesh. To determine the presence of LSDV in nodular tissues, we initially used iiPCR and PCR, followed by histopathological examination. 151 were positive via iiPCR and PCR among the 180 collected samples. The PCR positive 151 samples were then inoculated into 10-day-old embryonated chicken eggs via the CAM route to isolate LSDV, confirmed through PCR. Subsequently, partial sequencing and phylogenetic analysis of the P32 gene were performed to determine the origin of the circulating LSDV strain. The immunogenicity of selected LSDV strains was assessed through an ELISA test. The PCR results revealed a distinct positive band at 192 bp in both the nodular tissue samples and the LSDV isolated from chicken embryo inoculations. Microscopic analysis of the nodular lesions revealed thickening of the epidermis, ballooning degeneration of keratinocytes, and proliferation of follicular epithelia. Additionally, mononuclear infiltration was observed at the demarcation line between infected and healthy tissue, with necrosis of muscular tissues beneath the epidermis. The LSDV isolate from Bangladesh exhibited a close genetic relationship with LSDV strains isolated from neighboring and other regional countries including India, Myanmar, and Mongolia. This observation strongly suggests the possibility of a transboundary spread of the LSD outbreak in Bangladesh during 2019-2020. The results of the immunogenicity test showed that the serum antibody titer remained at a protective level for up to 18 months following secondary immunization with inactivated LSDV antigen. This finding suggests that the inactivated LSDV antigen could be a potential vaccine candidate to protect cattle in Bangladesh against LSDV. In conclusion, our research successfully isolated, identified, and characterized LSDV in cattle nodular tissues from the 2019-20 outbreak in Bangladesh. Furthermore, it provided insights into the probable origin of the circulating strain and investigated a potential vaccine candidate to protect cattle in the region from LSDV.

Molecular characterization of lumpy skin disease virus in North Central Vietnam during 2021 and early 2022.

In October 2020, the first outbreaks of lumpy skin disease (LSD) in Lang Son Province, Vietnam were reported by our laboratory. The disease had rapidly spread to the South, and it was reported in 55 of 63 provinces and cities of Vietnam by the end of 2021. The most economic loss caused by this disease occurred in the north-central region in 2021 where approximately 46,788 LSD virus (LSDV) infected cattle and buffaloes have been reported and 8,976 animals have been culled. However, the information on this pathogen circulating in this region is missing. Here, we describe the molecular characterization of LSDV circulating in north-central Vietnam in 2021 and early 2022. In total, 155 LSDV samples were collected during this period and three of these samples from each province were further characterized by Sanger sequencing analysis based on three key maker genes (GPCR, RPO30, and p32). Sequence comparison and phylogenetic analysis based on GPCR, RPO30, and p32 genes indicated that LSDV strains circulating in north-central Vietnam are closely related to previously reported strains in Vietnam regions which bordered China and all LSDV strains were 100% identical. These results show the importance of continuous monitoring and characterization of circulating LSDV strains and are important for vaccine development for the control and eradication of LSD in Vietnam.

Space–Time Clustering and Climatic Risk Factors for Lumpy Skin Disease of Cattle in Uttar Pradesh, India, 2022

Lumpy skin disease (LSD), a transboundary infectious disease, negatively impacts cattle health and production. The first LSD outbreaks were reported in India in 2019, and since then, LSD spread to over 15 states, including Uttar Pradesh. This study evaluated LSD cases reported by veterinarians in Uttar Pradesh, India, during 2022. Using scan statistics, Poisson models that accounted for the background cattle population were constructed to identify spatial, temporal, and space–time clusters. A negative binomial regression model was built to assess the impact of temperature and humidity on the incidence rate (IR) of LSD. A total of 112,226 cases across 33 districts were reported in 2022. A purely temporal cluster with higher-than-expected LSD rates was identified between August and October 2022. Several purely spatial clusters were identified in the western part of the state. A primary space–time cluster was detected in west Utter Pradesh between August and October 2022 that overlapped with the spatial clusters. The secondary cluster occurred between September and October 2022 in the eastern part of the state. A rise in humidity (incidence rate ratio (IRR) = 1.39; 95% CI: 1.30–1.49) and temperature (IRR = 1.16; 95% CI: 1.06–1.27) increased the IR of LSD, suggesting a seasonality of the outbreaks. The results of this study can aid animal health authorities in developing effective LSD prevention, surveillance, and control strategies among cattle in India.

Spatiotemporal analysis and forecasting of lumpy skin disease outbreaks in Ethiopia based on retrospective outbreak reports.

Lumpy skin disease is a viral disease that affects cattle belonging to genus Capripoxvirus (Poxviridae) and lead to significant economic losses. The objective of this study was to evaluate the distribution of lumpy skin disease (LSD) outbreaks and predict future patterns based on retrospective outbreak reports in Ethiopia. Data were collected through direct communication with regional laboratories and a hierarchical reporting system from the Peasant Associations to Ministry of Agriculture. Time-series data for the LSD outbreaks were analyzed using classical additive time-series decomposition and STL decomposition. Four models (ARIMA, SARIMA, ETS, STLF) were also used to forecast the number of LSD outbreaks that occurred each month for the years (2021-2025) after the models' accuracy test was performed. Additionally, the space-time permutation model (STP) were also used to study retrospective space-time cluster analysis of LSD outbreaks in Ethiopia. This study examined the geographical and temporal distribution of LSD outbreaks in Ethiopia from 2008 to 2020, reporting a total of 3,256 LSD outbreaks, 14,754 LSD-positive cases, 7,758 deaths, and 289 slaughters. It also covered approximately 68% of Ethiopia's districts, with Oromia reporting the highest LSD outbreaks. In the LSD's temporal distribution, the highest peak was reported following the rainy season in September to December and its lowest peak in the dry months of April and May. Out of the four models tested for forecasting, the SARIMA (3, 0, 0) (2, 1, 0) [12] model performed well for the validation data, while the STLF+Random Walk had a robust prediction for the training data. Thus, the SARIMA and STLF+Random Walk models produced a more accurate forecast of LSD outbreaks between 2020 and 2025. From retrospective Space-Time Cluster Analysis of LSD, eight possible clusters were also identified, with five of them located in central part of Ethiopia. The study's time series and ST-cluster analysis of LSD outbreak data provide valuable insights into the spatial and temporal dynamics of the disease in Ethiopia. These insights can aid in the development of effective strategies to control and prevent the spread of the disease and holds great potential for improving efforts to combat LSD in the country.

Molecular characterization of recombinant LSDV isolates from 2022 outbreak in Indonesia through phylogenetic networks and whole-genome SNP-based analysis

Lumpy skin disease (LSD) is a transboundary viral disease of cattle and water buffaloes caused by the LSD virus, leading to high morbidity, low mortality, and a significant economic impact. Initially endemic to Africa only, LSD has spread to the Middle East, Europe, and Asia in the past decade. The most effective control strategy for LSD is the vaccination of cattle with live-attenuated LSDV vaccines. Consequently, the emergence of two groups of LSDV strains in Asian countries, one closely related to the ancient Kenyan LSDV isolates and the second made of recombinant viruses with a backbone of Neethling-vaccine and field isolates, emphasized the need for constant molecular surveillance. This current study investigated the first outbreak of LSD in Indonesia in 2022. Molecular characterization of the isolate circulating in the country based on selected LSDV-marker genes: RPO30, GPCR, EEV glycoprotein gene, and B22R, as well as whole genome analysis using several analytical tools, indicated the Indonesia LSDV isolate as a recombinant of LSDV_Neethling_vaccine_LW_1959 and LSDV_NI-2490. The analysis clustered the Indonesia_LSDV with the previously reported LSDV recombinants circulating in East and Southeast Asia, but different from the recombinant viruses in Russia and the field isolates in South-Asian countries. Additionally, this study has demonstrated alternative accurate ways of LSDV whole genome analysis and clustering of isolates, including the recombinants, instead of whole-genome phylogenetic tree analysis. These data will strengthen our understanding of the pathogens’ origin, the extent of their spread, and determination of suitable control measures required.

Analysis of environmental factors influencing lumpy skin disease outbreak seasonality and assessment of its spread risk in the Saratovskaya oblast of Russia.

Lumpy skin disease (LSD) is a transboundary viral disease of cattle that causes serious economic losses due to a significant decrease in meat and milk productivity. This study analyzed the influence of natural and anthropogenic environmental factors on LSD spread seasonality and assessed the risk of LSD outbreaks in the Saratovskaya oblast of the Russian Federation. Data on LSD outbreaks and environmental factors during different seasons were collected for the period 2011-2020 in the Balkan Peninsula, Middle East, and Russia. Risk assessment was performed using mathematical modeling with generalized linear regression and maximum entropy. Fourteen statistically significant environmental factors influencing LSD spread were identified. The analysis of MaxEnt models built using the selected factors showed that the presence of the pathogen is mostly exerted by: the density of susceptible cattle (an increased risk is observed at a density above 10 and 20 heads/10 km2 in winter and autumn, with a permanent risk in spring and summer), the density of water bodies (the risk is increased at any density in winter and autumn, in the range of 13-23.5 m2/km2 in spring, in the ranges of 0-8 and over 14.5 m2/km2 in summer), and average monthly precipitation rate (the most risky are 105-185 mm/month in winter, 35 mm in spring, 15-105 mm in summer, and above 50 mm in autumn). LSD tends to spread during the warm season. Compared with other test zones, the Saratovskaya oblast has a negligible risk of disease spread (in winter), low risk (in spring), or medium risk (in summer and autumn). The annual risk is low to medium.

Review on the Economic Impacts of Lumpy Skin Disease of Cattle and its Prevention and Control Strategies in Ethiopia

Lumpy skin disease (LSD) is an infectious disease of cattle, caused by a Lumpy Skin Disease Virus. It is an economically important viral disease of cattle affecting all ages and breeds that can be prevented by vaccination in endemic regions including Ethiopia. LSD is an OIE listed disease because of considerable financial losses and in Ethiopia due to the endemic nature of LSD; the country is facing serious difficulties in exporting live cattle and their products. In addition, this situation contributes a negative impact on the national economic growth through the loss of meat and milk production and poor quality of skin and hides. Serious economic losses can follow outbreaks that have a high morbidity and high mortality rates of 40 percent or more have been encountered. There is no specific antiviral treatment available for LSD-infected cattle. The disease is now the problem of almost all the regions and agro ecological zones of Ethiopia. Major outbreaks of LSD have been occurred in different regions of Ethiopia. Two vaccines, however, Neethling and Kenya sheep and goat pox virus, have been used widely in Africa with success. Preventing movement the diseased animals along with vector control, regular annual vaccinations and awareness creation for cattle owners play great role in disease prevention and control. The disease outbreak was observed in the cattle regardless of previous vaccination with Kenyan sheep- and goat pox vaccine the occurrence of LSD outbreak scale, despite the use of a vaccination regime, is suggestive of vaccine failure. Apparent emerging vaccine failure is a serious problem for efficient control of LSD, as the disease has been manifested by high morbidity and mortality rates, regardless of vaccination status. Consequently continuous surveillance on the status of the disease and genetic information on circulating field viruses is mandatory in order to take effective measures for the control of the disease in the country.

Analysis of factors associated with the first lumpy skin disease outbreaks in naïve cattle herds in different regions of Thailand.

Thailand experienced a nationwide outbreak of lumpy skin disease (LSD) in 2021, highlighting the need for effective prevention and control strategies. This study aimed to identify herd-level risk factors associated with LSD outbreaks in beef cattle herds across different regions of Thailand. A case-control study was conducted in upper northeastern, northeastern, and central regions, where face-to-face interviews were conducted with farmers using a semi-structured questionnaire. Univariable and multivariable mixed effect logistic regression analyses were employed to determine the factors associated with LSD outbreaks. A total of 489 beef herds, including 161 LSD outbreak herds and 328 non-LSD herds, were investigated. Results showed that 66% of farmers have operated beef herds for more than five years. There were very few animal movements during the outbreak period. None of the cattle had been vaccinated with LSD vaccines. Insects that have the potential to act as vectors for LSD were observed in all herds. Thirty-four percent of farmers have implemented insect control measures. The final mixed effect logistic regression model identified herds operating for more than five years (odds ratio [OR]: 1.62, 95% confidence interval [CI]: 1.04-2.53) and the absence of insect control management on the herd (OR: 2.05, 95% CI: 1.29-3.25) to be associated with LSD outbreaks. The implementation of insect-vector control measures in areas at risk of LSD, especially for herds without vaccination against the disease, should be emphasized. This study provides the first report on risk factors for LSD outbreaks in naïve cattle herds in Thailand and offers useful information for the development of LSD prevention and control programs within the country's context.