Raffreddore, influenza e Covid-19 colpiscono di più in inverno a causa del freddo. La scoperta è stata fatta da un gruppo di ricerca di un’ospedale specializzato in malattie di occhi e orecchie della Harvard Medical School e ribalta la convinzione più diffusa finora, ovvero che la causa principale della diffusione sia da ricercare nel maggior tempo passato dalle persone in luoghi chiusi.
Il freddo sopprime la prima linea delle difese immunitarie messe in atto nel naso, la principale via d'ingresso dei virus che infettano le vie aeree. Uno studio del 2018, guidato dallo stesso istituto, aveva scoperto l'esistenza della risposta immunitaria innescata proprio dall'ingresso nel naso di batteri e virus. Ora i ricercatori hanno dimostrato che il meccanismo è influenzato dalla temperatura.
La scoperta, pubblicata risultati sul The Journal of Allergy and Clinical Immunology, apre a soluzioni terapeutiche mirate su questo punto debole, come spray nasali che rinforzino le difese immunitarie.
Covid, 80000 ricoverati nel 2020 e 2021
Telegiornale 05.12.2022, 21:00
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