A new coronavirus found in the Swedish bank vole

New virus Studies show that researchers have reported the discovery of the Gimso virus, a new beta coronavirus in bank voles (“Myodes glareolus) From Grimso, Sweden. These findings underscore the importance of maintaining monitoring of the human-wildlife interface for early detection of potential pandemic viruses.

study: Discovery of a new coronavirus in the Swedish European vole (Myodes glareolus).. Image Credit: corlaffa / Shutterstock.com

Preface

coronavirus Due to the wide host range of (CoV), the viral structural sequences are significantly different, increasing the likelihood of zoonotic diseases. CoV, which is known to cause human illness, comes primarily from rodents or bats.

Four endemic seasonal human CoVs were circulating long before the emergence of severe acute respiratory syndrome (SARS) -CoV, Middle East respiratory syndrome (MERS) -CoV, and SARS-CoV-2. These early endemic CoVs cause about one-third of the common colds in humans, two of which are closely associated with rodent-borne CoVs.

Therefore, rodents are likely to be a reservoir of CoV and can eventually spread to humans with events that could cause human infection.

Bank voles are commonly found in Europe and carry pathogens for multiple zoonotic diseases, including: Tree orthohantavirus When Wild rabbit fungus.. Both alpha and beta CoV have been detected in these animals at various times.

In the current study, researchers report the discovery of two complete grimsovirus sequences and their phylogenetic relationships with other rodent CoVs. These sequences were taken from a three-year sampling of bank voles at a single site in Grimso, Sweden, between 2015 and 2017.

Survey results

Researchers initially used a customized polymerase chain reaction (PCR) assay to screen about 270 bank voles. This resulted in nine partial sequences that shared 98-100% and 94-100% identity of nucleotides and amino acids, respectively. The same sequence was less than 60% identical to other rodent beta CoVs at the nucleotide level and less than 50% at the amino acid level.

(A) A geographical map showing the state of Örebro in Sweden and the location of the sampling where the bank vole was captured (Grimsö). A table showing the spread of the Grimso virus from 2015 to 2017. (B) Mr Bayes midpoint root tree based on 252 nt of spike gene. The scale bar shows the site-by-site nt substitution. The numbers on the branches indicate posterior probabilities. The Grimso virus sample is highlighted in blue.

Further analysis showed that these partial sequences came from distinct phylogenetic groups that formed part of the rodent embecovirus.

Using two of these sequences, researchers obtained a complete sequence with seven regions containing spikes, envelopes, nucleocapsids, and membrane proteins. These sequences were found to share less than 80% and 67% of the nucleotide and amino acid sequences with other rodent CoVs, respectively. This shows the difference from other known rodent CoVs.

Comparing between 101 CoV genomic sequences, the ribonucleic acid (RNA) -dependent RNA polymerase (RdRp) enzyme sequence was composed of three unique alpha and beta CoV species of bank honeybees.These CoVs belong to Lucaco virus When Embecovirus From the genus Alphacoronavirus and the genus Betacoronavirus, respectively. However, no common receptor sequence was identified, except for the S2 domain of the peplomer.

Implications

The current study discusses the discovery of a new beta CoV in the Swedish bank vole and presents its complete sequence for the first time. The failure to detect this virus using the published pan-CoV PCR test is due to the highly diverse RNA sequences of the Grimso virus. The use of specific spike gene primers in the customized PCR used in this study yielded several samples over a three-year study period.

The two complete sequences obtained in this study showed almost 3.5% non-identity. This corresponds to a difference of about 1,340 at the nucleotide level. This is higher than the expected nucleotide substitution rate over 3 years. Some strains of grimsovirus co-circulate in this rodent species, or the true reservoir of this virus contains other species that regularly infect bank voles.

The prevalence of grimsovirus in this rodent species is about 3.4%, suggesting that this animal is a suitable host for the virus. As a result, the Grimso virus is a potential zoonotic host of spillover events between bank voles and humans.

Bank voles have been shown to carry several different CoVs across a wide range of Europe, including those closely related to the grimsovirus. In addition, recombination and cross-species transmission events are often recorded, leaving an urgent need to carry out additional research to map and monitor this virus.