PREreview of "Two incursions, two viruses: Emergence of a second novel Shamonda virus clade in Central Europe, 2026"

Abstract

This Zenodo record is a permanently preserved version of a PREreview. You can view the complete PREreview at https://prereview.org/reviews/23748929. Summary The preprint proposes that there are two distinct clades of the Shamonda virus (SHAV), a midge-borne virus that infects cattle, sheep, and goats recently found in Europe, from two different introductions. They used RT-qPCR to distinguish between the new virus and the related Schmallenberg virus (SBV). They conducted a phylogenetic analysis to distinguish this sample as a new clade separate from the previously known SHAV strain. The researchers call for further research into the pathways of introduction to inform surveillance and preventive measures. Strengths Multiple genomic approaches to confirm genetic novelty. One strength of the study was the use of multiple genomic tests to ensure the SHAV virus was identified appropriately. Using PCR testing, L- and M-segment based tests, and three-segment genome testing to differentiate SHAV from SBV and SHAV-EU1 from SHAV-EU2 resulted in clear evidence of the two strands. The study brings attention to a virus of which there is increasing concern. In France, there was recently the first human death from SHAV. There is no vaccine or treatment for SHAV. This preprint provides more information on the spread of SHAV and the possibility of multiple introductions, which is important for diagnostics, risk evaluation, and control measures. Major concerns Samples may not be representative. The samples were collected by veterinarians through routine health monitoring rather than a standardized random selection. They may have been collected because the veterinarians suspected the cattle were infected with something, which would bias the findings. The actual geographic distribution of SHAV-EU2 may differ from what the preprint concludes. Cannot claim there are two independent introductions. It is possible that there was a single introduction, and one clade was circulating undetected. The commentary explicitly assumes that there were two independent introductions within the same time frame, though it would be more appropriate to interpret these findings cautiously. Competing interests The authors declare that they have no competing interests. Use of Artificial Intelligence (AI) The authors declare that they did not use generative AI to come up with new ideas for their review.