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Fig. 4 | Virology Journal

Fig. 4

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. 4

HAI titers against A/Darwin/9/2021(H3N2) in sera from 2021 and 2022 in different age groups. A) Reverse cumulative plots were generated from the HAI titers against A/Darwin/9/2021 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 were extracted from the Norwegian Laboratory Database for the period week 1 2022 to week 26 2022. C) Reverse cumulative plots of HAI titers in sera from one reference lab tested against A/Darwin/9/2021 in both 2021 and 2022. Significant differences were calculated by a two-tailed Mann-Whitney test. *** = p < 0.001 and ns = no significant difference

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Virology Journal

ISSN: 1743-422X