Coding-Complete Genome Sequences of Emerging Rabbit Hemorrhagic Disease Virus Type 2 Isolates Detected in 2020 in the United States.

Five rabbit hemorrhagic disease virus type 2 (RHDV2) coding-complete genome sequences were obtained from the livers of domestic and wild rabbits during the 2020 outbreak in the United States. These represent the first available RHDV2 sequences from the United States.

Genome Sequences of Vesicular Stomatitis Indiana Viruses from the 2019 Outbreak in the Southwest United States.

We report the genomes of three vesicular stomatitis Indiana virus (VSIV) isolates collected from naturally infected bovines in Wyoming and Colorado during the 2019 outbreak in the United States. These genomes support molecular diagnostic efforts and provide data on the spread and ecology of VSIV in the United States.

Diagnostic approaches for Rift Valley fever.

Disease outbreaks caused by arthropod-borne animal viruses (arboviruses) resulting in significant livestock and economic losses world-wide appear to be increasing. Rift Valley fever (RVF) virus is an important arbovirus that causes lethal disease in cattle, camels, sheep and goats in Sub-Saharan Africa. There is concern that this virus could spread because of global warming, increased animal trade or through bioterrorism. This paper discusses the current and developing approaches to diagnosis of RVF. Diagnostic assays are available for RVF, but availability can be limited and there is a need for global harmonization. Continued improvement of standard serological and viral genome amplification approaches, including new embedded/syndromic testing, biosensor, emerging virus detection and characterization technologies is needed.

Molecular detection of Ehrlichia ruminantium infection in Amblyomma variegatum ticks in The Gambia.

In West Africa, losses due to heartwater disease are not known because the incidence/prevalence has not been well studied or documented. To develop a diagnostic tool for molecular epidemiology, three PCR-based diagnostic assays, a nested pCS20 PCR, a nested map1 PCR and a nested reverse line blot (RLB) hybridization assay, were evaluated to determine their ability to detect infection in vector ticks, by applying them simultaneously to A. variegatum field ticks to detect Ehrlichia ruminantium, the causative agent of heartwater. The nested pCS20 PCR assay which amplified the pCS20 gene fragment showed the highest detection performance with a detection rate of 16.6%; the nested map1 PCR, which amplified the gene encoding the major antigenic protein1 (map1 gene) showed a detection rate of 11% and the RLB, based on the 16S rDNA sequence of anaplasma and ehrlichial species, detected 6.2%. The RLB, in addition, demonstrated molecular evidence of Ehrlichia ovina, Anaplasma marginale and Anaplasma ovis infections in The Gambia. Subsequently, the pCS20 assay was applied to study the prevalence and distribution of E. ruminantium tick infection rates at different sites in five divisions of The Gambia. The rates of infection in the country ranged from 1.6% to 15.1% with higher prevalences detected at sites in the westerly divisions (Western, Lower River and North Bank; range 8.3-15.1%) than in the easterly divisions (Central River and Upper River; range 1.6-7.5%). This study demonstrated a gradient in the distribution of heartwater disease risk for susceptible livestock in The Gambia which factor must be considered in the overall design of future upgrading programmes.