Evidence of lumpy skin disease virus over-wintering by transstadial persistence in Amblyomma hebraeum and transovarial persistence in Rhipicephalus decoloratus ticks

Abstract

Lumpy skin disease is a debilitating cattle disease caused by the lumpy skin disease virus (LSDV), belonging to the genus Capripoxvirus. Epidemics of the disease usually occur in summer, when insect activity is high. Limited information is available on how LSDV persists during inter-epidemic periods. Transmission of LSDV by mosquitoes such as Aedes aegypti has been shown to be mechanical, there is no carrier state in cattle and the role of wildlife in the epidemiology of the disease seems to be of minor importance. Recent studies in ticks have shown transstadial persistence of LSDV in Rhipicephalus appendiculatus and Amblyomma hebraeum as well as transovarial persistence of the virus in Rhipicephalus decoloratus, R. appendiculatus and A. hebraeum. The over-wintering of ticks off the host as part of their life cycles is well known: A. hebraeum and R. appendiculatus over-winter, for example, on the ground as engorged nymphs/unfed (emergent) adults while R. decoloratus over-winters on the ground as engorged females. In this study, transstadial and transovarial persistence of LSDV from experimentally infected A. hebraeum nymphs and R. decoloratus females after exposure to cold temperatures of 5 °C at night and 20 °C during the day for 2 months was reported. This observation suggests possible over-wintering of the virus in these tick species.

Lumpy skin disease: Attempted propagation in tick cell lines and presence of viral DNA in field ticks collected from naturally-infected cattle

“…(B.) decoloratus larvae, originating from similarly infected fully engorged females ( Lubinga et al, 2014b ). Based on the evidence obtained from the present study, in addition to the previous investigations, we suggest that viable and infective LSDV may only survive in tick cells and tissues without actual replication; nevertheless this survival may be sufficient to result in transmission by the next life cycle stage following attachment and feeding on a susceptible host.…”

Review: Capripoxvirus Diseases: Current Status and Opportunities for Control

“…() reported the potential role of ixodid ticks in the transmission of LSDV. Transovarial transmission of LSDV by Rhipicephalus (Boophilus) decoloratus , mechanical or intrastadial transmission by Rhipicephalus appendiculatus and Amblyomma hebraeum males, as well as trans‐stadial transmission by Amblyomma hebraeum have now been reported (Lubinga et al., , ; Tuppurainen et al., ,b).…”

Hematological, biochemical and oxidative stress studies of lumpy skin disease virus infection in cattle

“…This disease is caused by LSD virus (LSDV), which belongs to the genus Capripoxvirus and the subfamily Chordopoxvirinae of the family Poxviridae (Buller et al 2005). LSDV is transmitted among cattle by biting insects (Lubinga et al 2014). LSDV infections cause significant economic losses in various respects, such as by inducing severely reduced milk production, weight loss, abortion, infertility and/or hide damage.…”