Age-seroprevalence curves for the multi-strain structure of influenza A virus

Abstract

The relationship between age and seroprevalence can be used to estimate the annual attack rate of an infectious disease. For pathogens with multiple serologically distinct strains, there is a need to describe composite exposure to an antigenically variable group of pathogens. In this study, we assay 24,402 general-population serum samples, collected in Vietnam between 2009 to 2015, for antibodies to eleven human influenza A strains. We report that a principal components decomposition of antibody titer data gives the first principal component as an appropriate surrogate for seroprevalence; this results in annual attack rate estimates of 25.6% (95% CI: 24.1% – 27.1%) for subtype H3 and 16.0% (95% CI: 14.7% – 17.3%) for subtype H1. The remaining principal components separate the strains by serological similarity and associate birth cohorts with their particular influenza histories. Our work shows that dimensionality reduction can be used on human antibody profiles to construct an age-seroprevalence relationship for antigenically variable pathogens.

Evaluating seasonal variations in human contact patterns and their impact on the transmission of respiratory infectious diseases

“…3A). Overall, the median infection attack rates range from 10% to 30% which is consistent with previous estimates for influenza [25][26][27] . As shown in Figure 3B, median peak week incidence is highest for an epidemic beginning on October 1 (698 new infections per 10,000 individuals; 95%CI: 3738 to 1,101) and lowest for an epidemic beginning on February 1 (200 new infections per 10,000 individuals; 95%CI: 39 to 442).…”

Characterizing the transmission patterns of seasonal influenza in Italy: lessons from the last decade

“…To our knowledge, there are no studies reporting estimates on seroconversion rates for seasonal influenza neither for Italy nor for other European countries to compare our results with. However, a recent study based on data collected in central and southern Vietnam between 2009 to 2015 estimated annual attack rates at 25.6% (95% CI: 24.1-27.1%) for H3 strains and at 16.0% (95% CI: 14.7-17.3%) for H1 strains [33], and another longitudinal study conducted in Hong Kong between 2009 and 2011 on influenza A estimated seroconversion rates as high as 22%, and slightly higher among the elderly for A/ H3N2 [34], which are in line with our estimates. When analyzing the infection attack rate by age, an even larger variability was estimated, mainly associated with the different infection patterns of the three types/subtypes.…”

Differential COVID-19 infection rates in children, adults, and elderly: evidence from 38 pre-vaccination national seroprevalence studies

“…Fourth, the counterfactual seroprevalence ratios in the absence of any restrictive measures are unknown. Evidence from influenza seroprevalence assessments suggests that often children and/or young adults may be infected more frequently than elderly individuals, perhaps due to greater mobility and exposures, but this is not absolute and may vary per year and location [24][25][26][27] .…”