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کد خبر : 185409

لزوم استفاده از دو ماسک برای مصونیت بیشتر در برابر کرونا

لزوم استفاده از دو ماسک برای مصونیت بیشتر در برابر کرونا

مرکز کنترل و پیشگیری از بیماری ها در آمریکا (سی‌دی‌سی) توصیه کرده است که پوشیدن یک ماسک پارچه ای علاوه بر یک ماسک جراحی به طور قابل توجهی حفاظت در برابر ذرات معلق عامل سرایت کرونا را افزایش می دهد. به گزارش ایسنا، این مرکز نتیجه تحقیقات خود روی انواع ماسک ها در محیط آزمایشگاهی

لزوم استفاده از دو ماسک برای مصونیت بیشتر در برابر کرونا

مرکز کنترل و پیشگیری از بیماری ها در آمریکا (سی‌دی‌سی) توصیه کرده است که پوشیدن یک ماسک پارچه ای علاوه بر یک ماسک جراحی به طور قابل توجهی حفاظت در برابر ذرات معلق عامل سرایت کرونا را افزایش می دهد.

به گزارش ایسنا، این مرکز نتیجه تحقیقات خود روی انواع ماسک ها در محیط آزمایشگاهی را منتشر کرد که نشان می دهد ترکیب دو ماسک پارچه ای و جراحی به طور چشمگیری خطر انتشار ویروس به دیگران یا قرار گرفتن در معرض ویروس را کم می کند.

براساس توصیه های تازه این مرکز از مردم خواسته می شود ماسکی را انتخاب کنند که سیم داشته باشد تا به درستی حالت بینی را به خود بگیرد و هوابندی شود. این سازمان توصیه می کند مردم کلیه منفذهای احتمالی اطراف ماسک را ببندند.

این سازمان همچنین توصیه می کند برای جلوگیری از عبور مستقیم (فیلتر نشده) هوا از لبه های ماسک، در صورت لزوم بندهای آن دور گوش گره زده شود و دو لبه کناری ماسک با دست صاف شود تا هوا از زیر آن رد نشود.

سی‌دی‌سی گفت در صورت استفاده از ماسک های حرفه ای “ان ۹۵” یا ماسک هایی با همین درجه حفاظت، دیگر نیازی به پوشیدن ماسک پارچه ای روی آن نیست.

کارشناسان می گویند پوشیدن ماسک پارچه ای روی ماسک جراحی باعث می شود منفذهای اطراف ماسک که درست روی صورت نمی نشیند خیلی بهتر بسته شود.

براساس مطالعه سی دی سی زمانی که در تست های آزمایشگاهی فقط از یک ماسک جراحی استفاده شد تنها ۴۲ درصد ذرات سرفه مسدود شد. اما افزودن یک ماسک پارچه ای روی آن ۹۲.۵ درصد ذرات پرت شده در اثر سرفه را مسدود کرد.

براساس این مطالعه ترکیب دو ماسک همچنین در مجموع قرار گرفتن در معرض ذراتی که از افرادی که ماسک نزده اند منتشر می شود را ۸۳ درصد کاهش داد. زمانی که هر دو منبع مورد آزمایش (در این مورد آدمک) دو ماسک داشتند میزان محافظت از این ذرات به ۹۶.۴ درصد رسید.

به گزارش بی بی سی، دکتر جان بروکس، محقق ارشد پزشکی و از نویسندگان مطالعه تازه نیز گفت: مطالعات انجام شده در خانه ها در پکن، سلمانی‌ها در میزوری و پروازها در گوام ثابت کرده که “زدن هر ماسکی بهتر از نزدن آن است.”

او گفت: پوشیدن ماسک میزان انتشار ویروس را کاهش می دهد و در جوامعی که ماسک زدن اجباری می شود، آمار ابتلا پایین می رود.

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