The human side of influenza

Abstract

Review of immunity to influenza virus infection in humans, noting evidence from murine studies and suggesting directions in which future research is most needed.

Mucosal Immune Responses Predict Clinical Outcomes during Influenza Infection Independently of Age and Viral Load

“…It is not understood why infection of previously healthy individuals can result in poor clinical outcomes, such as bronchiolitis, pneumonia, or acute respiratory distress syndrome, and particularly during pandemic years, there is a disproportionate rate of hospitalization and death compared with nonpandemic years, supporting the argument for protective contributions of preexisting immunity. Although much has been learned from human challenge studies, relatively few reports examine natural influenza infection in humans, particularly in the traditionally vulnerable pediatric and elderly populations, and rarely at the site of infection (1)(2)(3)(4)(5)(6)(7).…”

Mutations in human genes that increase the risk for severe influenza infection

“…One of the significant discoveries made during the years, passed after the last pandemic, was the detection of polymorphism in gene IFITM3 in groups of patients who developed a severe course of disease, caused by influenza virus A(H1N1)pdm09, with fatal complications in a number of cases ( Fig.1) [9,[13][14][15][16][17][18][19][20][21].…”

“…These studies have fundamental significance for pediatric practice and global epidemic processes [9,14,17]. The group of genes that have an impact on the development of complications over the course of influenza, is significantly widening over the years [9,17]. Table 1 presents a list of these genes and their probable role in the disruption of certain functions contributing to the eradication of influenza and other viral infections.…”

“…On the one hand, the direct connection is established between a complicated course of influenza and haplotype HLA (Human Leukocyte Antigenes). On the other hand, the analysis of a number of gene polymorphisms, which determine the level of anti-viral defense, confirms that the contribution of single mutations and singlenucleotide polymorphisms (SNP) to the morbidity and mortality from influenza is significantly higher than was previously considered [7][8][9][10][11][12]. Large scale studies on population genetics and sensitivity to influenza prove that the anti-epidemic actions in different regions of the country should be planned in accordance to the specific genetic characteristics of population.…”

“…To that end, it is necessary to systematize the available information on genomes and the corresponding markers, distinctive for the cases with inadequate or pathological reaction to influenza and other accompanying infections. The SNP of the genes, listed and characterized below, is connected with the enhancement of human sensitivity to influenza or complicated course of this disease [9,13,14].…”