Transmission of lumpy skin disease virus: A short review

Chander

et al. 2020

Preprint

Lumpy skin disease (LSD) has devastating economic impact. During the last decade, LSD had spread to climatically new and previously disease-free countries, which also includes its recent emergence in the Indian subcontinent (2019). This study deals with the LSD outbreak(s) from cattle in Ranchi (India). Virus was isolated from the scabs (skin lesions) in the primary goat kidney cells. Phylogenetic analysis based on nucleotide sequencing of LSD virus (LSDV) ORF011, ORF012 and ORF036 suggested that the isolated virus (LSDV/Bos taurus-tc/India/2019/Ranchi) is closely related to Kenyan LSDV strains. Further, we adapted the isolated virus in Vero cells, an alternative cell line that was found suitable for LSDV propagation. In addition, kinetics of viral DNA synthesis and one-step growth curve analysis suggested that LSDV initiates synthesizing its genome at ∼24 hours post-infection (hpi) with a peak level at ∼96 hpi whereas evidence of progeny virus particles was observed at 36-48 hours (h) with a peak titre at ∼120 h. This study reports the first successful isolation of LSDV in India, besides describing alternative cells for virus isolation (primary goat kidney cells) and in vitro propagation (Vero cells) as well as providing some insights on LSDV life cycle.Author SummaryThis study describes the first successful isolation of LSDV in India. Nucleotide sequencing of LSDV ORF011, ORF012 and ORF036 suggested that the isolated virus is closely related to Kenyan LSDV strains. This is in accordance with the previous (only) study, thereby suggesting that a single LSDV strain is circulating in India. For the first time, we employed primary goat kidney (PGK) cells for the isolation of LSDV, where PGK cells were found more sensitive for LSDV isolation as compared to the primary lamb testicle (PLT) and primary goat testicle (PGT) cells. We also adapted the isolated virus in Vero cells and demonstrated that Vero cells are also suitable for in vitro propagation of LSDV. Besides, we also provide some insights on the LSDV life cycle.

Section: Discussionmentioning

confidence: 83%

Section: Discussionmentioning

confidence: 99%

Isolation and characterization of lumpy skin disease virus from cattle in India

Chander

et al. 2020

Preprint

“…Sequencing of LSDV isolates recovered from outbreaks in 2018 demonstrated that LSDV variants indeed harbor KSGP-like sequences (Fig 1). The prevailing view that LSDV is only vector-borne [10] and the unavailability of the full-genome sequence of the Kenyan Lumpivax isolate greatly impede progress in…”

Section: Plos Onementioning

confidence: 99%

Evidence of recombination of vaccine strains of lumpy skin disease virus with field strains, causing disease

et al. 2020

Vaccination against lumpy skin disease (LSD) is crucial for maintaining the health of animals and the economic sustainability of farming. Either homologous vaccines consisting of live attenuated LSD virus (LSDV) or heterologous vaccines consisting of live attenuated sheeppox or goatpox virus (SPPV/GPPV) can be used for control of LSDV. Although SPPV/ GTPV-based vaccines exhibit slightly lower efficacy than live attenuated LSDV vaccines, they do not cause vaccine-induced viremia, fever, and clinical symptoms of the disease following vaccination, caused by the replication capacity of live attenuated LSDVs. Recombination of capripoxviruses in the field was a long-standing hypothesis until a naturally occurring recombinant LSDV vaccine isolate was detected in Russia, where the sheeppox vaccine alone is used. This occurred after the initiation of vaccination campaigns using LSDV vaccines in the neighboring countries in 2017, when the first cases of presumed vaccine-like isolate circulation were documented with concurrent detection of a recombinant vaccine isolate in the field. The follow-up findings presented herein show that during the period from 2015 to 2018, the molecular epidemiology of LSDV in Russia split into two independent waves. The 2015-2016 epidemic was attributable to the field isolate. Whereas the 2017 epidemic and, in particular, the 2018 epidemic represented novel disease importations that were not genetically linked to the 2015-2016 field-type incursions. This demonstrated a new emergence rather than the continuation of the field-type epidemic. Since recombinant vaccine-like LSDV isolates appear to have entrenched across the country's border, the policy of using certain live vaccines requires revision in the context of the biosafety threat it presents.

“…In recent decades, the disease has been documented in both Southern and Northern hemispheres due to a rapid expansion of its range, although historically, it was restricted to the African continent [8][9][10] . The unprecedented incursions into new territories and resurgence of LSD creates an objective need for joint efforts to investigate the obscure nature of LSDV transmission 11 .…”

mentioning

confidence: 99%

Non-vector-borne transmission of lumpy skin disease virus

Кононов

Byadovskaya

David

et al. 2020

Sci Rep

The transmission of "lumpy skin disease virus" (LSDV) has prompted intensive research efforts due to the rapid spread and high impact of the disease in recent years, especially in eastern europe and Balkan countries. in this study, we experimentally evaluate the vaccine-derived virulent recombinant LSDV strain (Saratov/2017) and provide solid evidence on the capacity of the virus for transmission in a vectorproof environment. In the 60-day long experiment, we used inoculated bulls (IN group) and two groups of in-contact animals (C1 and C2), with the former (C1) being in contact with the inoculated animals at the onset of the trial and the latter (C2) being introduced at day 33 of the experiment. The infection in both groups of contact animals was confirmed clinically, serologically and virologically, and viremia was demonstrated in blood, nasal and ocular excretions, using molecular tools. further studies into LSDV biology are a priority to gain insights into whether the hypothesized indirect contact mode evidenced in this study is a de novo-created feature, absent from both parental stains of the novel (recombinant) LSDV isolate used, or whether it was dormant, but then unlocked by the process of genetic recombination. Author summary: in global terms, LSD has been termed a "neglected disease" due to its historic natural occurrence of being restricted to Africa and, occasionally, israel. However, after its slow spread throughout the Middle east, the disease is now experiencing a resurgence of research interest following a recent and rapid spread into more northern latitudes. Given the dearth of solid findings on potential transmission mechanisms, no efficient or reliable control program currently exists, which does not involve the use of live attenuated vaccines or stamping out policies-both of which are controversial for implementation in non-endemic regions or countries. the vector-borne mode is the only working concept currently available, but with scarce evidence to support the aggressive spread northwards-except for human-assisted spread, including legal or illegal animal transportation. the emergence of outbreaks is not consistently linked to weather conditions, with the potential for new outbreaks to occur and spread rapidly. Here, for the first time, we provide evidence for indirect contact-mode transmission for a naturally-occurring recombinant LSDV isolated from the field. In an insect-proof facility, we obtained solid evidence that the novel LSDV strain can pass to in-contact animals. Given the recombinant nature of the virus utilised, its genetic background relating to the observed transmission pattern within the study needs to be delineated.