Definition: In this task, you're given a paragraph from the research paper and your task is to generate a suitable title for the research paper based on the given paper. Under 100 words is a good title length.
Input: To monitor oseltamivir-resistant infl uenza viruses A (H1N1) (ORVs) with H275Y in neuraminidase (NA) in Japan during 2 infl uenza seasons, we analyzed 3,216 clinical samples by NA sequencing and/or NA inhibition assay. The total frequency of ORVs was 2.6% (45/1,734) during the 2007-08 season and 99.7% (1,477/1,482) during the 2008-09 season, indicating a marked increase in ORVs in Japan during 1 infl uenza season. The NA gene of ORVs in the 2007-08 season fell into 2 distinct lineages by D354G substitution, whereas that of ORVs in the 2008-09 season fell into 1 lineage. NA inhibition assay and M2 sequencing showed that almost all the ORVs were sensitive to zanamivir and amantadine. The hemagglutination inhibition test showed that ORVs were antigenetically similar to the 2008-09 vaccine strain A/Brisbane/59/2007. Our data indicate that the current vaccine or zanamivir and amantadine are effective against recent ORVs, but continuous surveillance remains necessary.

Oseltamivir-Resistant Infl uenza Viruses A (H1N1) during 2007-2009 Infl uenza Seasons, Japan the Working Group for Infl uenza Virus Surveillance in Japan 1