Phylogenetic reconstructions
Nucleotide sequences were translated and aligned using the MUSCLE algorithm implemented in MEGA. Sequences (147 to 396 nucleotides) generated in this work have been deposited in GenBank with the following accession numbers:OR493270-OR493385.
For type characterization, phylogenetic trees were constructed using ModelFinder, tree reconstruction and ultrafast bootstrap (1000 replicates) with IQ-TREE 2.1.3. RSV reference sequences used were in File S2. The best-fit nucleotide substitution model GTR+F+G4 was identified according to Bayesian information criterion. Bootstrap values were estimated using the SH test and ultrafast bootstrap with 1000 replicates. To identify the phylogenetic relationship, 8373 G gene sequences type A and 5339 type B available in the GenBank database (one sequence of each type used for the Basic Local Alignment Search Tool (BLAST) in March 2023) were used (File S2). Transmission clusters were defined as viral sequences circulating in Asturias grouped into a single and well supported monophyletic clade with >90% bootstrap values. To search for mutations, the sequences were compared with ON1 (JN257693) and BA9 (DQ227395).