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Birch pollen

Birch (Betula pendula, Betula pubescens) está en el aire aquí desde april to june, pico late April to mid-May in the Baltic, the first half of May in southern Finland, and late May to early June in Lapland. Potencia alergénica: high. Reacciona de forma cruzada conapple, pear, cherry, plumy otros.

Esto es información de referencia, no un diagnóstico ni un plan de tratamiento. Un calendario de polen no puede decirle a qué es alérgico, y ninguna página puede declarar un alimento seguro para usted — solo la etiqueta del paquete en la mano y el clínico que conoce su historia. Cualquier cosa más allá de síntomas leves y de corta duración en boca o nariz — hinchazón que afecta la respiración o la deglución, urticaria lejos de la boca, sibilancias, vómito o desmayo — es una pregunta de emergencia, no de lectura.

● semanas pico · ○ habitualmente en el aire. Ventana continental típica de los programas nacionales de vigilancia aerobiológica de la región · comprobado2026-09-06

Dónde crece aquí

Birch is the defining tree of this region and the single most important outdoor allergen in it. Silver birch and downy birch together cover a large share of the forest area of Estonia, Latvia, Lithuania, Finland and Sweden, they colonise every clearing and roadside, and they are planted in gardens and along streets in every town. There is no realistic way to avoid the source.

Cuándo está en el aire

The birch season is short, violent and highly variable between years. In the Baltic states the heaviest days usually fall between the last week of April and mid-May; southern Finland runs a week or so later; Lapland can be four weeks later still. The tree also masts, so a heavy flowering year is often followed by a lighter one, and a single warm, dry, windy week can compress most of the season into a few days.

Cómo se siente

Eyes are usually the worst of it: swollen, streaming, gritty, worse in wind. Add a blocked nose, sneezing, an itchy palate and, for many people, genuine exhaustion — the constant low-grade inflammation and broken sleep of a bad May is not imagined. Asthma symptoms commonly step up during the peak fortnight.

Con qué reacciona de forma cruzada

Bet v 1 is the reason birch matters far beyond hay fever. It is a PR-10 protein, and near-identical proteins occur in apple (Mal d 1), stone fruit, hazelnut (Cor a 1), carrot (Dau c 1), celery (Api g 1), soy (Gly m 4) and peanut (Ara h 8). An immune system trained on birch pollen recognises them, and biting into a raw apple in May produces an itchy mouth. This is pollen-food allergy syndrome, and in birch country it is the most common food allergy in adults.

Pólenes relacionados:alder, hazel, oak, hornbeam and beech.

Alimentos con reacción cruzada notificada:

ApplePearCherryPlumPeachApricotHazelnutAlmondCarrotCeleryParsnipSoy drink and tofuPeanutKiwi

Una reacción cruzada no es lo mismo que una alergia alimentaria que empezó con el alimento, y la diferencia decide cuán grave es. Lea cómo funciona el síndrome de alergia oral antes de sacar conclusiones de esta lista, y note que varios de estos alimentos también aparecen en los catorce alérgenos UE declarables por razones enteramente separadas.

Moléculas alergénicas nombradas:Bet v 1 (PR-10, the major allergen), Bet v 2 (profilin), Bet v 6. Estos son los nombres oficiales WHO/IUIS, y es lo que informa un análisis de sangre de resolución de componentes.

Qué ayuda de verdad

Birch pollen is one of the five types the CAMS European model forecasts, so a daily number exists. Preventive treatment works better than rescue treatment: nasal steroid sprays need days to reach full effect, so they are started before the season, not during it. Birch is also the classic candidate for allergen immunotherapy, which is a clinician-led, multi-year decision — not something to start from a web page.

Qué se lee mal

Two things get confused every year. First, a raw apple causing an itchy mouth in May is birch, not "an apple allergy" — the same apple baked in a pie is usually fine, because Bet v 1 homologues fall apart with heat. Second, the peak is not the whole season: the tail in late May still carries enough pollen to keep symptoms going after the visible catkins have gone.

Fuentes:Reglamento (UE) n.º 1169/2011, anexo II· Reglamento de ejecución (UE) n.º 828/2014 de la Comisión (declaraciones de gluten)· Nomenclatura de alérgenos WHO/IUIS· ventanas de temporada de los programas nacionales de vigilancia aerobiológica de Estonia, Finlandia, Suecia, Dinamarca y Noruega· patrones de reacción cruzada parafraseados de la literatura alérgica y material de EAACI· comprobado2026-09-06

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