Isolation and Pathogenicity of a Getah Virus With a Novel Deletion in the 3 ^′ UTR

The spread of Getah virus (GETV) in China has become increasingly severe due to long‐term neglect and the lack of vaccines, posing a threat to animal safety and public health. In this study, we isolated and identified a novel GETV strain, designated GETV‐CX7. Phylogenetic analysis of the E2 gene and the complete genome showed that GETV‐CX7 belongs to Group III. Notably, sequence analysis revealed a novel 14‐nucleotide deletion near the 5 ’ end of the 3 ’ untranslated region (UTR) of GETV‐CX7. RNA Secondary Structure Package (RNAfold) predictions further revealed that this deletion changes the RNA secondary structure of the 3 ’ UTR in GETV‐CX7. Additionally, pathogenicity experiments demonstrated 100% mortality in mice infected with GETV‐CX7 via subcutaneous or intracerebral routes. GETV‐CX7‐infected mice exhibited tissue lesions, including hemorrhaging in the brain, lungs, and kidneys, as well as intestinal wall thinning. GETV‐CX7 exhibits broad tissue tropism, particularly in the brain, with a viral load of up to 6.2 log 10 PFU/g by 3 days postchallenge (dpc). In summary, we isolated a novel GETV Group III strain, GETV‐CX7, characterized by a 14‐nt deletion in the 3 ’ UTR, which exhibited high pathogenicity in 5‐day‐old mice.