Antibodies to influenza virus hemagglutinin in the 2016/2017 epidemic season in Poland

Abstract

The aim of the study was to determine the level of antibodies against hemagglutinin of influenza viruses in the sera of 1,050 patients stratified into 7 different age groups during the 2016/2017 epidemic season in Poland. The method consisted of using the hemagglutination inhibition test (HAI). The findings confirmed the presence of anti-hemagglutinin antibodies against the following influenza virus antigens: A/California/7/2009 (H1N1) pdm09, A/Hong Kong/4801/2014 (H3N2), and B/Brisbane/60/2008. The level of anti-hemagglutinin antibodies differed across the age groups investigated, with the highest values in patients aged 10–14 years. We also found that the protection factor was highest for B/Brisbane/60/2008 antigen. It amounted to 72.7% in 10–14-year olds and to 69.3% in both 15–25 and 26–44-year olds. Taking into account a dismally low percentage of vaccinated population in the 2016/2017 epidemic season in Poland, amounting to barely 3.33%, the findings should be interpreted as representing the patients’ immune system response to influenza virus infection.