As birch pollen peaks throughout the UK this spring, health experts are warning of the worsening hay fever season and advising key protective measures. Spring in the UK isn't all about flowers blooming and sunshine, it's also the height of hay fever season. Health experts and the UK Met Office now implore residents across the country to take an unprecedented but crucial step- shut windows and doors between 10am and 3pm, especially in areas of high pollen. It comes after a sudden increase in tree pollen, particularly birch, which is forecast to hit "very high" levels in many areas this week.Pollen counts in the air usually rise from mid-morning to mid-afternoon. During that window, when the sun becomes more intense and wind speeds increase, pollen becomes airborne and is more prevalent. Sealing your doors and windows during this time frame can greatly reduce your exposure.“It’s extremely beneficial to keep windows and doors closed during certain hours of the day, particularly when it’s windy,” explained a Met Office spokesperson. “Right now, we’re in tree pollen season, with birch being the most dominant and allergenic.”These alerts are based on ideal conditions for pollen dispersal: warm, dry weather, low rainfall, and wind. Unfortunately for allergy sufferers, that’s exactly what the UK has experienced in recent weeks.What's Causes Hay Fever?The culprit of this year's worst allergy onslaught? Birch pollen.Tree pollen season typically begins in March and lasts until mid-May. Birch trees, one of the UK's most allergenic tree species, are booming this year after ideal growing conditions last spring and summer. According to the Met Office, this has led to above-average levels of pollen.Tree pollen affects around 25% of hay fever sufferers, but this could be more this year as a result of the record amounts seen in most parts of the nation.Hay Fever SymptomsHay fever, or seasonal allergic rhinitis, affects more than 10 million people in the UK. It occurs when pollen enters the body and the immune system reacts by treating it as a foreign invader, producing histamines that induce symptoms such as:SneezingWatery, itchy eyesRunny or blocked noseSore or itchy throatSleep and tirednessIn some cases, hay fever can exacerbate asthma symptoms, leading to wheezing, coughing, and shortness of breath.How to Protect Yourself This Season?Although hay fever cannot be avoided, there are some good methods to minimize exposure and alleviate symptoms:Consult local pollen predictions and limit outdoor activity low at peak times.Keep doors and windows shut, especially between 10am and 3pm.Use home air cleaners or HEPA filters in your vehicle.Shower and launder after spending time outside to eliminate pollen grains.Use antihistamines or nasal sprays—many are available over the counter.Rinse pollen from nasal passages with a saline solution.These easy actions can make a dramatic difference in quality of life in spring and summer.Where Pollen Levels Are 'Very High' This WeekAccording to the latest pollen forecast map published by the Met Office, the following regions are of concern with extremely high pollen concentration:Monday: East of England, London, South East, East MidlandsTuesday: West Midlands, East Midlands, Eastern England, London, South EastWednesday and Thursday: London, Kent, Sussex, Surrey, Essex, Suffolk, Norfolk, CambridgeshireWhen to Seek Doctor Help?If symptoms persist with over-the-counter medication, or hay fever begins to disrupt activities, consult a medical doctor. Allergy testing, prescription medication, or perhaps even immunotherapy (allergy shots) might be needed for long-lasting relief.Hay fever is usually underestimated, but in severe cases, it can impact sleep, focus, and general well-beingparticularly in children, seniors, and individuals with asthma.