The Genotyping tool at the NCBI identifies the genotype (or subtype) of viral sequences by using a sliding window approach to BLAST analysis against reference sequences for different viral subtypes. Results are shown as a graphical output plotting the top-scoring genotype. An alignment tool is also available.
The NCBI Influenza Virus Sequence Annotation Tool is a web application for user-provided sequences. It can predict protein sequences encoded by an input flu sequence and produce a feature table that can be used for sequence submission to GenBank.