Hay fever sufferers are being warned that the warm weather has encouraged ash and birch trees to flower early this spring, and that the symptoms could be confused with coronavirus.

People who are allergic to tree pollen may find themselves suffering from runny noses and coughs in the coming days, according to researchers at the Leiden teaching hospital.

‘Some of the hay fever symptoms are similar to complaints which are found in COVID-19 patients,’ the researchers said. ‘An allergic reaction could worry hay fever sufferers and people close to them, so they need to be aware of this.’

COVID-19 symptoms include a runny nose, coughing, a sore throat and a temperature. Hay fever patients suffer from a tickly cough, runny nose, streaming eyes and fits of sneezing.

Hay fever sufferers should start taking medication early in readiness for the pollen season, avoid woods with flowering birch trees and keep doors and windows shut, the researchers say.

The birch pollen peak is expected around April 5.