Endemic and Emerging Arboviruses in Domestic Ruminants in East Asia

Abstract

Epizootic congenital abnormalities caused by Akabane, Aino, and Chuzan viruses have damaged the reproduction of domestic ruminants in East Asia for many years. In the past, large outbreaks of febrile illness related to bovine ephemeral fever and Ibaraki viruses severely affected the cattle industry in that region. In recent years, vaccines against these viruses have reduced the occurrence of diseases, although the viruses are still circulating and have occasionally caused sporadic and small-scaled epidemics. Over a long-term monitoring period, many arboviruses other than the above-mentioned viruses have been isolated from cattle and Culicoides biting midges in Japan. Several novel arboviruses that may infect ruminants (e.g., mosquito-and tick-borne arboviruses) were recently reported in mainland China based on extensive surveillance. It is noteworthy that some are suspected of being associated with cattle diseases. Malformed calves exposed to an intrauterine infection with orthobunyaviruses (e.g., Peaton and Shamonda viruses) have been observed. Epizootic hemorrhagic disease virus serotype 6 caused a sudden outbreak of hemorrhagic disease in cattle in Japan. Unfortunately, the pathogenicity of many other viruses in ruminants has been uncertain, although these viruses potentially affect livestock production. As global transportation grows, the risk of an accidental incursion of arboviruses is likely to increase in previously non-endemic areas. Global warming will also certainly affect the distribution and active period of vectors, and thus the range of virus spreads will expand to higher-latitude regions. To prevent anticipated damages to the livestock industry, the monitoring system for arboviral circulation and incursion should be strengthened; moreover, the sharing of information and preventive strategies will be essential in East Asia.

Detection and Phylogenetic Analysis of a Novel Tick-Borne Virus in Yunnan and Guizhou Provinces, Southwestern China

“…In recent years, more and more novel arboviruses have been identified from various vector hosts [ 10 , 11 ]. Additionally, a growing number of novel TBVs were also discovered throughout the world, for instance, BRBV in USA [ 4 ], ALSV in China [ 5 ], Hunter island group virus (HIGV) in Australia [ 12 ], Muko virus (MUV), and Tarumizu tick virus (TarTV) in Japan [ 13 , 14 ], etc.…”

Immunoinformatics Approach to Design Multi-Epitope- Subunit Vaccine against Bovine Ephemeral Fever Disease

“…Only recently, the awareness of BEFV prophylaxis gained attention. Although a few BEFV vaccines are now available commercially, they revealed only limited effectiveness [15]. A few inactivated vaccines showed high neutralizing antibody titers to BEFV challenge, but failed to trigger effective cell-mediated immune (CMI) responses [16].…”

Complete genome sequencing and assessment of mutation-associated protein dynamics of the first Indian bovine ephemeral fever virus (BEFV) isolate

“…Previous studies have suggested BEFV to possess high substitution rates (Trinidad et al 2014 ). However, few recent reports on the generation of novel genogroups with higher viral virulence (Yanase et al 2020 ) and limited vaccine effectiveness suggest BEFV evolution is enhancing variant's fitness landscape to help overcome the host immune system (Aziz-Boaron et al 2014 ).…”

“…The new geographical expansions with enhanced case fatality rate and high production losses alarm BEFV as an evolving arbovirus that warrants closer scrutiny in surveillance, epidemiology, and ecological impact (Lee 2019 ; Yanase et al 2020 ). Despite the multiple decades of episodic reporting on seasonal incursions from many South Asian countries, including India (Nandi and Negi 1999 ; Walker and Klement 2015 ), no complete sequence information was available until recently (Pyasi et al 2020 ), which hinders progress for its detection and prevention.…”