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Fig. 3 | Virology Journal

Fig. 3

From: Correction: antigenic drift and immunity gap explain reduction in protective responses against influenza A(H1N1)pdm09 and A(H3N2) viruses during the COVID-19 pandemic: a cross-sectional study of human sera collected in 2019, 2021, 2022, and 2023

Fig. 3

HAI titers against H1N1pdm09 A/Victoria/2570/2019 in sera from 2021 and 2022 in different age groups. A) Reverse cumulative plots were generated from the HAI titers against A/Victoria/2570/19 from 2021 and 2022 for the age groups 0–4 years, 5–14 years, 15–24 years, 25–59 years and 60 + years. The dotted line indicates 50% protective HAI titer of 40. B) Number of detected influenza A infections per 100.000 individuals in the different age groups for the period week 40 2022 to week 22 2023. C) Vaccine coverage in the general population obtained from the Norwegian Immunization Registry SYSVAK for the different age groups. D) Reverse cumulative plots of HAI titers in a panel of 119 sera collected in 2021 and first tested against A/Victoria/2570/2019 in 2021 and repeat tested in 2022 to verify reproducibility. A) Significant differences were calculated by a two-tailed Mann-Whitney test. ** = p < 0.01, *** = p < 0.001 and**** = p < 0.0001, ns = no significant difference

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Virology Journal

ISSN: 1743-422X