12/23/2023 0 Comments Peazip virus freeIn addition to virus being transmitted between several mammalian host species through direct contact and fomites, multiple insect species play a role in transmission as biological and mechanical vectors. ![]() Previous comparative infection studies in swine showed that the epidemic lineage 1.1 had an increased ability to disrupt innate immune responses, caused higher fever, and presented with an increased number of vesicular lesions compared with infections using the closely related endemic lineage 1.2. Although the specific impact of these amino acid mutations is still unclear, additional evolutionary studies have suggested a potential relevance during the evolution of VSV strains and a role in mediating the immune response in the mammalian host. These amino acid changes were classified mostly as favorable or neutral however, seven non-synonymous substitutions between the two lineages were predicted to significantly affect protein size, charge, or hydrophobicity. Further studies indicated that genetic differences between the epidemic (1.1) and endemic (1.2) lineages included 111 nucleotide substitutions associated with 23 amino acid changes in four out of the five viral proteins encoded by VSV. Phylogenetic characterization suggested that the closest common endemic ancestor of lineage 1.1 was lineage 1.2, a group of viruses confined in the endemic area in Veracruz, Mexico. In 2012, a specific VSV-NJ lineage, 1.1, spread northward through central and northern Mexico and made an incursion into the southern U.S. These epidemic viruses are associated with a distinct viral lineage, closely related to endemic lineages circulating in Mexico. border and spread as far north as Wyoming, lasting for a single year (incursion year), or often re-emerging for a second year (expansion year). Historically, VS outbreaks initiated in the Mexico-U.S. In the U.S., where VS is not endemic, outbreaks display an occurrence pattern of five to ten-year intervals. VS is endemic in tropical and subtropical regions of the Americas. Thus, in addition to affecting virus-animal interactions, as seen with higher virulence in pigs, small genetic changes may also affect virus-vector interactions, contributing to the ability of specific viral lineages to escape endemic regions via vector-borne transmission. Our results showed that midges orally infected with the epidemic VSV 1.1 lineage had significantly higher infection dissemination rates compared to those infected with the endemic VSV 1.2 lineage. Here, we compared the efficiency of these two viral lineages to infect the vector Culicoides sonorensis (Wirth and Jones) and disseminate to salivary glands for subsequent transmission. Previous studies in swine showed that VSV 1.1 was more virulent than VSV 1.2. Whole-genome sequencing of epidemic VSV 1.1 and endemic VSV 1.2 revealed significant differences in just seven amino acids. It is not clear what roles virus-animal interactions and/or virus-vector interactions play in the ability of specific viral lineages to escape endemic regions in Mexico and successfully cause outbreaks in the U.S., nor the genetic basis for such incursions. ![]() In contrast, the closest endemic ancestor, lineage 1.2, remained circulating exclusively in endemic regions in Mexico. In 2012, a monophyletic epidemic lineage 1.1 successfully spread northward into the U.S. Endemic to Central and South America, specific VSV lineages spread northward out of endemic regions of Mexico and into the U.S. Vesicular stomatitis virus (VSV) primarily infects livestock and is transmitted by direct contact and vectored by Culicoides midges (Diptera: Ceratopogonidae).
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |