Frequent Isolations of Influenza A Viruses (H1N1)pdm09 with Identical Hemagglutinin Sequences for More Than Three Months in Japan.

ABSTRACT:

Background

Although it has been suggested that antigenic drift does not occur in a single epidemic season in temperate countries, there is not enough evidence on the circulation period of influenza virus with identical nucleotide sequences. Therefore, strains of influenza virus were isolated sequentially during five consecutive epidemic seasons in Japan and their nucleotide sequences were determined.

Methods

Nasal swabs or aspirated nasal discharges were collected from influenza A virus antigen-positive individuals living in Tottori Prefecture, Japan for five consecutive winters starting in 2009-2010, and subjected to viral isolation, determination of hemagglutinin nucleotide sequence and phylogenic analyses. The nucleotide sequences were compared with each other and also wi

SUBMITTER: Yoshida Y 

PROVIDER: S-EPMC4701988 | biostudies-literature | 2015 Dec

REPOSITORIES: biostudies-literature