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کووید-۱۹ احتمالا شبیه آنفلوآنزای فصلی می‌شود

کووید-۱۹ احتمالا شبیه آنفلوآنزای فصلی می‌شود

همزمان با ادامه تاخت‌وتاز جهانی کووید-۱۹ و اوج‌گیری آمار کشته‌شدگان و افراد بستری در بیمارستان‌ها در چند کشور جهان، شناخت پزشکان و محققان از این ویروس در حال افزایش است. به گزارش ایسنا، هنگامی که همه‌گیری شروع شد، مردم در ابتدا امید داشتند واکسن بتواند ویروس را از بین ببرد و به تحقق “مصونیت جمعی”

کووید-۱۹ احتمالا شبیه آنفلوآنزای فصلی می‌شود

همزمان با ادامه تاخت‌وتاز جهانی کووید-۱۹ و اوج‌گیری آمار کشته‌شدگان و افراد بستری در بیمارستان‌ها در چند کشور جهان، شناخت پزشکان و محققان از این ویروس در حال افزایش است.

به گزارش ایسنا، هنگامی که همه‌گیری شروع شد، مردم در ابتدا امید داشتند واکسن بتواند ویروس را از بین ببرد و به تحقق “مصونیت جمعی” در جهان کمک کند اما مقامات بهداشتی هشدار داده‌اند که این ویروس ممکن است مثل آنفلوآنزا هر سال بازگردد.

بر اساس تحقیقات بیشتری که اکنون در مورد کووید-۱۹ انجام شده، این ویروس ممکن است تا ابد در جوامع بشری ماندگار باشد ولی میزان ابتلا و تلفات ناشی از آن به اندازه همه‌گیری کنونی نخواهد بود.

دکتر جان براونستاین، کارشناس ارشد نوآوری در بیمارستان کودکان بوستون در مصاحبه ای با شبکه خبری “ای‌بی‌سی” مدعی شد: این ویروس کرونا باقی می‌ماند و از بین بردن آن اساسا غیرممکن است.

پیش‌بینی دکتر براونستاین با تحقیقی که به تازگی انجام شده است نیز همخوانی دارد.

طبق یافته‌های این تحقیق، ویروس سارس- کوو-۲ ،عامل کووید-۱۹ در نهایت همراه با سایر عوامل بیماری‌زای ویروس کرونا به صورت فصلی و با علایم خفیف، دوباره بازمی‌گردد.

اما این موضوع به همه‌گیری محلی کووید-۱۹ بستگی دارد. یعنی به گفته محققان دانشگاه اموری در دانشگاه ایالتی جورجیا و پن، ممکن است ویروس دیگر در مقیاس وسیع شایع نباشد یا دایما بیماری جدی در کشورهای مختلف ایجاد نکند.

جنی لواین، نویسنده اصلی این مطالعه نیز در مصاحبه با نیویورک‌تایمز گفت: این که چقدر طول بکشد تا به مرحله همه‌گیری محلی برسیم، بستگی به سرعت شیوع بیماری و میزان تاثیر واکسیناسیون دارد.

کووید-۱۹ بر دستگاه ایمنی بزرگسالان در سطحی وسیع اثر مخربی گذاشت چون یک عامل بیماری‌زای ناشناخته‌ بود و بدن به مبارزه با این ویروس جدید عادت نداشت. اما احتمال می رود هرچه بزرگسالان بیشتری واکسن کووید-۱۹ را بزنند یا خودبه‌خود به این ویروس مبتلا و درمان شوند، واکنش بدن انسان به این ویروس تغییر می‌کند و می‌تواند علیه این عامل بیماری‌زا، خود را ایمن کند. طبق برآورد این متخصصان، این باعث می‌شود واکنش بدن در برابر عفونت‌های بعدی، شبیه واکنش آن در برابر یک سرماخوردگی عادی باشد.

از طرفی، کودکان در مقایسه با بزرگسالان هنوز تحت تاثیر این ویروس جدید قرار نگرفته‌اند چون بدن آنان به مقابله با عوامل بیماری‌زای جدید عادت دارد. متخصصان پیش‌بینی می‌کنند شاید سرانجام طوری پیش رود که این ویروس فقط برای کودکان زیر پنج سال خطرناک باشد.

در این مطالعه، شش نوع ویروس کرونای انسانی بررسی شدند که چهار مورد آن‌ها بین انسان‌ها شایع شده و علایم خفیفی در پی داشته است. دو مورد دیگر، نشانگان شدید تنفسی (سارس) و نشانگان تنفسی خاورمیانه‌ای (مرس) بودند که به ترتیب در سال‌های ۲۰۰۳ و ۲۰۱۲ شایع و موجب عفونت شدید و مرگ شدند اما در مقیاس وسیع سرایت نکردند.

دکتر لواین و گروه همکاران وی حدس زده‌اند که کووید-۱۹ بیشترین شباهت را به ویروس‌های کرونای محلی عامل سرماخوردگی دارد یعنی ممکن است در آینده به جای آن که کاملا از بین برود به بیماری فصلی تبدیل شود.

استفاده از واکسن، بسته به میزان اثرگذاری‌ و تزریق آن، ممکن است روند پیشروی ویروس جدید را تغییر دهد.

اگر واکسن از سرایت ویروس در میان افراد جلوگیری کند، نتیجه می‌گیریم که باید مانند واکسن سرخک یک بار به همه تزریق شود اما اگر مانع سرایت نشود، ممکن است برای پیشگیری از شیوع عفونت، لازم باشد هر سال تجدید شود.

به نوشته روزنامه ایندیپندنت، دکتر لواین و گروهش پیش‌بینی می‌کنند واکسن‌ها نخواهند توانست کووید-۱۹ را ریشه‌کن کنند و ویروس روی زمین باقی خواهد ماند اما باعث مرگ‌ومیر کمتری خواهد شد.

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