Silent Infection of B and CD8 + T Lymphocytes by Influenza A Virus in Children with Tonsillar Hypertrophy

Abstract

Influenza A virus (IAV) infections are important threats to human health worldwide. Although extensively studied, some aspects of virus pathogenesis and tissue tropism remain unclear. Here, by different strategies, we describe the asymptomatic infection of human lymphoid organs by IAV in children. Our results indicate that IAV was not only detected and isolated from human tonsils but displayed unique genetic features in comparison with those of contemporaneous IAVs circulating in Brazil and detected in swabs and nasal washes. Inside the tissue microenvironment, immune cells were shown to be carrying IAV antigens, especially B and T CD8 + lymphocytes. Taken together, these results suggest that human lymphoid tissues can be sites of silent IAV infections with possible impact on virus shedding to the population.