Pollen likely seasonal factor in inhibiting flu-like epidemics. A Dutch study into the inverse relation between pollen counts, hay fever and flu-like incidence 2016–2019

Martijn J Hoogeveen

doi:10.1016/j.scitotenv.2020.138543

Martijn J Hoogeveen

Open Access

https://doi.org/10.1016/j.scitotenv.2020.138543

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Abstract

There is uncertainty if current models for the Covid-19 pandemic should already take into account seasonality. That is because current environmental factors do not provide a powerful explanation of such seasonality, especially given climate differences between countries with moderate climates. It is hypothesized that one major factor is overlooked: pollen count. Pollen are documented to invoke strong immune responses and might create an environmental factor that makes it more difficult for flu-like viruses to survive outside a host. This Dutch study confirms that there is a (highly) significant inverse correlation between pollen count and weekly changes in medical flu consults, and that there is a highly significant inverse correlation between hay fever incidence, as measured by prescribed medication revenues, and weekly flu consults. This supports the idea that pollen are a direct or indirect factor in the seasonality of flu-like epidemics. If seasonality will be observed during the covid-19 spread as well, it is not unlikely that pollen play a role.

Highlights

Virologists observe already for many years that the cold, and flulike epidemics “go away in May” in the Northern Hemisphere, to move to the Southern Hemisphere, M.J
To hypothesize in what ways pollen could be an environmental factor influencing the life cycle of flu-like epidemics, the objective of this quick study is to falsify the hypothesis that there are no significant inverse correlations between pollen counts, pollen induced immune responses, and flu-like epidemic life cycles in The Netherlands
Given the burst like phenomenon, it is not strange that we found no clear correlation between pollen count and the incidence of flu-like medical consults for our data set

Summary

Introduction

Virologists observe already for many years that the cold, and flulike epidemics (influenza and corona caused) “go away in May” in the Northern Hemisphere, to move to the Southern Hemisphere, M.J. Hoogeveen / Science of the Total Environment 727 (2020) 138543 be completely satisfactory to explain the seasonality of flu-like epidemics, which is very important to understand in the light of ongoing modelling efforts for the current Covid-19 pandemic. To hypothesize in what ways pollen could be an environmental factor influencing the life cycle of flu-like epidemics, the objective of this quick study is to falsify the hypothesis that there are no significant inverse correlations between pollen counts, pollen induced immune responses, and flu-like epidemic life cycles in The Netherlands. Environmental view might lead to new insights (Reijnders and Hoogeveen, 2001)

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