Bayesian estimation of joint transitions between full-length NA and SΔNA and selected HA features.

a: Difference of all rates that lead to the character combinations feature present/SΔNA and feature absent/full-length-NA minus all rates that lead the character combinations feature absent/SΔNA and feature present/full-length-NA (refer to Methods).b: Blanks in HA sequences that are associated with SΔNA are designated as deletions and blanks in HA sequences that are associated with full-length-NA are designated as insertions in HA sequences associated with SΔNA.c: NA deletion pattern IDs that are associated with the HA feature that has a higher proportion among AIVs with SΔNA than among AIVs with full-length-NA.d: There is no exact corresponding position on the H3 sequence. This position is on an insertion between position 159 and 160 on the H3 sequence.