Severe hay fever is an unpleasant allergic condition that can be a real problem for extreme sufferers, especially in certain parts of the UK where the allergen count tends to be high – whether it is flower pollen (such as rapeseed) or tree pollen (such as silver birch). Apparently, there are 3 billion trees in the UK, that’s 47 for every Briton.
Know more: https://www.travel-doc.com/vaccinations/hayfever-treatment/