A decade genetic diversity in Circulating influenza B virus in Iran (2010-2019): Divergence from WHO-recommended vaccine strains.

BACKGROUND: Data on the disease burden and circulation patterns of influenza B virus lineages for Iran are limited. OBJECTIVE: This review aims to describe the pattern of influenza B occurrence in Iran, comparing it with the proposed vaccine strains and determining the match and mismatch with the prescribed vaccine annually. METHODS: Various sources were used to retrieve information of the data; such as information from an online search of databases such as FluNet, GISAID, and NCBI. After extracting protein sequence records in GISAID, sequence alignment with vaccine strain and construction of a phylogenetic tree were performed. Subsequently, categories of the registered circulating strains were evaluated for matching with the vaccine strains. RESULTS: Of the total registered influenza-positive samples, 20.21% were related to influenza B virus. The phylogenic tree was designed based on 43 samples registered in the GISAID database; 76.74 and 23.25% sequences were of Yamagata and Victoria lineages, respectively. The most prevalent influenza B virus strains circulating during the study years belonged to the Yamagata lineage. In general, the match of the influenza B virus predominant circulating strains with administrated vaccines was observed in Iran. However, a high level of mismatch between the vaccine strain and Iranian isolates was identified in 2016‒2017. CONCLUSION: The review of match and mismatch in influenza vaccine in order to improve the composition of the prescribed vaccine in each region is very important because the vaccine efficacy decreased when the strain included in vaccine did not match the circulating epidemic strain.

Electrochemical biosensing of influenza A subtype genome based on meso/macroporous cobalt (II) oxide nanoflakes-applied to human samples.

Meso/macroporous cobalt (II) oxide nanoflakes were electrodeposited in a one-step process in the presence of N-methylpyrrolidone. On the surface of nanoflakes, a specific single stranded DNA sequence from the genome of influenza A subtype was then immobilized to fabricate an electrochemical biosensor. Hybridization of the biosensor with complementary, non-complementary and base-mismatch sequences was electrochemically detected. The biosensor was also employed to detect complementary DNA of viral RNA in culture and human samples. The biosensor could detect the complementary sequence with a detection limit of 86.4 amol L-1 and a linear concentration range of 1.0 fmol L-1 to 1.0 nmol L-1. It also detected a complementary DNA sequence converted from viral RNA with a detection limit of 0.28 ng µL-1 in a linear concentration range of 0.5-10 ng µL-1. Low detection limit, simple method of preparation of the transducer and no needing any DNA strand modification and tag are the principal advantages of the biosensor.