Ineffectiveness of the 2014-2015 H3N2 influenza vaccine

Abstract

The seasonal influenza vaccine is currently the most effective preventive modality against influenza infection. Nasopharyngeal samples of vaccinated and non-vaccinated patients presenting with Influenza-like-illness (ILI) were collected from over 20 outpatient clinics located in different geographic parts of Israel and were tested for the presence of influenza viruses (influenza A and influenza B). Here we show, that in the 2014-2015 season, the vaccine that included the A/Texas/50/2012 H3N2 virus was ineffective. Significant numbers of individuals vaccinated with the 2014-2015 vaccine, of all ages, were infected with influenza A (H3N2), manifesting similar symptoms as the non-vaccinated group. We further demonstrate that the Israeli circulating influenza A(H3N2) virus was different than that included in the 2014-2015 northern hemisphere vaccine, and that antibodies elicited by this vaccine were significantly less efficient in neutralizing influenza A(H3N2) infection.

Predominance of a Drifted Influenza A (H3N2) Clade and Its Association with Age-Specific Influenza Vaccine Effectiveness Variations, Influenza Season 2018–2019

“…Prior to the 2018-2019 season, influenza A (H3N2) viruses belonging to the 3C.3 clade circulated in Israel only during the 2013-2014 season [10]. Although the influenza A (H3N2) viruses circulating in Israel during 2018-2019 demonstrated genetic homogeneity within the 3C.3a clade, the 2018-2019 influenza A (H3N2) viruses circulating in European countries and the United States demonstrated genetic diversity within the 2C.2a clade [16][17][18][19][20].…”

“…The viral genomic RNA was extracted using MagNApure 96 (Roche, Mannheim, Germany). The presence of influenza viruses A and B and influenza subtype were examined by real-time reverse transcription polymerase chain reaction (rRT-PCR), using Ambion Ag-Path master mix and TaqMan Chemistry (qRT-PCR), performed in the ABI 7500 Real-Time PCR System (Thermo Fisher Scientific, USA), as previously described [10]. Hemagglutinin (HA) gene sequencing was performed on a subset of viruses selected from different months throughout the 2018-2019 influenza season.…”

“…Hemagglutinin (HA) gene sequencing was performed on a subset of viruses selected from different months throughout the 2018-2019 influenza season. The influenza A (H3N2) HA gene was partially amplified using specific primers [3,4,8,10]. The amplified HA RT-PCR products were sequenced as previously described [4].…”

Genetic divergence of Influenza A(H3N2) amino acid substitutions mark the beginning of the 2016–2017 winter season in Israel

“…During that period, the influenza A(H3N2) vaccine component was modified several times [18] . Amino acid substitutions in the HA protein are considered to occur more frequently in influenza A(H3N2) than in influenza A(H1N1) [3] , [19] , [20] , and a significant drift was detected during the 2014–2015 season in the northern hemisphere, dominated by the 3C.2a clade [7] , [21] . Based on available vaccination data, 20% of ILI sentinel patients and at least 36% of hospitalized influenza A(H3N2)-positive cases became ill in the beginning of the 2016-2017 season despite being vaccinated.…”

“…Influenza A, Influenza B and A(H1N1)pdm09 infection was detected by using a panel of real-time reverse transcription-PCR (rRT-PCR), as previously described [5] , [6] . For influenza A(H3N2) detection and sequencing specific primers were used as previously described [7] .…”