Research Summary: Shortcomings of Vitamin D-Based Model Simulations of Seasonal Influenza


Seasonal variation in serum concentration of the vitamin D metabolite 25(OH)
vitamin D [25(OH)D], which contributes to host immune function, has
been hypothesized to be the underlying source of observed influenza seasonality
in temperate regions. The objective of this study was to determine whether
observed 25(OH)D levels could be used to simulate observed influenza infection
rates. Data of mean and variance in 25(OH)D serum levels by month were obtained
from the Health Professionals Follow-up Study and used to parameterize an
individual-based model of influenza transmission dynamics in two regions of the
United States. Simulations were compared with observed daily influenza excess
mortality data. Best-fitting simulations could reproduce the observed seasonal
cycle of influenza; however, these best-fit simulations were shown to be highly
sensitive to stochastic processes within the model and were unable consistently
to reproduce observed seasonal patterns. In this respect the simulations with
the vitamin D forced model were inferior to similar modeling efforts using
absolute humidity and the school calendar as seasonal forcing variables. These
model results indicate it is unlikely that seasonal variations in vitamin D
levels principally determine the seasonality of influenza in temperate


Publisher: Public Library of Science

Date Published: 3-June-2011

Author(s): Shaman J., Jeon C., Giovannucci E., Lipsitch M.


Leave a Reply