Ara\u015ft\u0131rmac\u0131lar h\u0131zl\u0131 yay\u0131lan koronavir\u00fcs varyant\u0131n\u0131n, COVID-19 a\u015f\u0131lar\u0131n\u0131n etkinli\u011fine kar\u015f\u0131 bir tehdit te\u015fkil edip etmedi\u011fini belirlemek i\u00e7in h\u0131zla \u00e7al\u0131\u015f\u0131yorlar. G\u00fcney Afrika\u2019daki ara\u015ft\u0131rmac\u0131lar, COVID-19 hastal\u0131\u011f\u0131na neden olan SARS-CoV-2 koronavir\u00fcs\u00fcn\u00fcn yeni varyant\u0131n\u0131n endi\u015fe veren y\u00fckseli\u015fini g\u00f6zlemleyebilmek i\u00e7in h\u0131z kesmeden \u00e7al\u0131\u015f\u0131yorlar. Yeni varyant, Delta da dahil olmak \u00fczere, di\u011fer varyantlarda bulunan \u00e7ok say\u0131da mutasyonu da bar\u0131nd\u0131r\u0131yor ve G\u00fcney Afrika\u2019da h\u0131zla yay\u0131l\u0131yor gibi g\u00f6r\u00fcn\u00fcyor.<\/p>\n
Birincil \u00f6ncelik; varyant\u0131 yay\u0131l\u0131rken daha yak\u0131ndan takip etmek: varyant, ilk olarak bu ay\u0131n ba\u015flar\u0131nda Afrika\u2019da bir \u00fclke olan Botsvana\u2019da tespit edildi ve o zamandan sonra G\u00fcney Afrika\u2019dan Hong Kong\u2019a gelen bir gezginde g\u00f6r\u00fcld\u00fc. Bunun yan\u0131nda bilim insanlar\u0131; bu varyant\u0131n, a\u015f\u0131lar sayesinde olu\u015fturulan ba\u011f\u0131\u015f\u0131kl\u0131k sistemi yan\u0131t\u0131ndan ka\u00e7\u0131p ka\u00e7amayaca\u011f\u0131 ve di\u011fer varyantlardan daha hafif ya da daha ciddi hastal\u0131\u011fa sebep olup olmayaca\u011f\u0131 gibi \u00f6zelliklerini anlamaya \u00e7al\u0131\u015f\u0131yorlar.
\nG\u00fcney Afrika\u2019n\u0131n Johannesburg \u015fehrindeki Witwatersrand \u00dcniversitesi\u2019nden virolog Penny Moore; \u201cSon h\u0131zda u\u00e7uyoruz\u201d diyor. Kendisinin laboratuvar\u0131 \u015fu anda bu varyant\u0131n, a\u015f\u0131lardan ve \u00f6nceki enfeksiyonlardan kaynakl\u0131 elde edilen ba\u011f\u0131\u015f\u0131kl\u0131\u011f\u0131 a\u015fabilme potansiyelini \u00f6l\u00e7meye \u00e7al\u0131\u015f\u0131yor. \u015eu anda, yeniden enfeksiyon ve a\u015f\u0131lanan bireylerdeki vakalara ili\u015fkin anekdot \u015feklinde raporlar var, lakin Moore, \u201cBu a\u015famada bir \u015fey s\u00f6ylemek i\u00e7in \u00e7ok erken\u201d, diyor.<\/p>\n
G\u00fcney Afrika\u2019n\u0131n Durban kentindeki KwaZulu-Natal \u00dcniversitesi\u2019nde enfeksiyon hastal\u0131klar\u0131 doktoru olan Richard Lessells, 25 Kas\u0131m tarihinde G\u00fcney Afrika\u2019n\u0131n sa\u011fl\u0131k departman\u0131 taraf\u0131ndan d\u00fczenlenen bas\u0131n toplant\u0131s\u0131nda, \u201cBu varyant hakk\u0131nda anlamad\u0131\u011f\u0131m\u0131z \u00e7ok \u015fey var\u201d dedi. Ve s\u00f6zlerine, \u201cMutasyon profili bize endi\u015fe veriyor, ancak \u015fimdi bu varyant\u0131n klinik ve pandemiye yap\u0131lan m\u00fcdahaleler a\u00e7\u0131s\u0131ndan anlam\u0131n\u0131 anlamak i\u00e7in \u00e7al\u0131\u015fmam\u0131z gerekiyor\u201d diye devam ediyor.
\n26 Kas\u0131m tarihinde D\u00fcnya Sa\u011fl\u0131k \u00d6rg\u00fct\u00fc (WHO), kendi b\u00fcnyesindeki SARS-CoV-2 Vir\u00fcs Evrimi \u00fczerinde g\u00f6revli olan Teknik Dan\u0131\u015fma Grubu\u2019nun par\u00e7as\u0131 olan bilim insanlar\u0131n\u0131n tavsiyesi \u00fczerine, B.1.1.529 olarak bilinen varyant\u0131, endi\u015fe uyand\u0131ran varyant (variant of concern) olarak belirledi ve varyant\u0131 Omicron olarak adland\u0131rd\u0131. Omicron, D\u00fcnya Sa\u011fl\u0131k \u00d6rg\u00fct\u00fc\u2019n\u00fcn mevcut endi\u015fe uyand\u0131ran varyantlar listesinde, Delta, Alpha, Beta ve Gamma\u2019ya kat\u0131l\u0131yor.
\nAra\u015ft\u0131rmac\u0131lar ayn\u0131 zamanda varyant\u0131n k\u00fcresel yay\u0131lma potansiyelini \u00f6l\u00e7mek istiyor. Yeni varyant muhtemelen yeni enfeksiyon dalgalar\u0131n\u0131 tetikleyecek ya da Delta varyant\u0131 y\u00fcz\u00fcnden ya\u015fanan art\u0131\u015flar\u0131 \u015fiddetlendirecek.<\/p>\n
Spike proteinindeki de\u011fi\u015fiklikler<\/strong> A\u015f\u0131 etkinli\u011fi<\/strong> \u0130ngiltere\u2019deki Oxford \u00dcniversitesi\u2019nde vir\u00fcs evrimi \u00fczerine \u00e7al\u0131\u015fan Aris Katzourakis, \u201cCevab\u0131 merakla beklenen soru \u015fu, \u2018yeni varyant\u0131n \u00e7ok fazla de\u011fi\u015fikli\u011fi oldu\u011fu i\u00e7in a\u015f\u0131n\u0131n etkinli\u011fi azal\u0131yor mu?\u2019\u201d, diyor. Moore, G\u00fcney Afrika\u2019da uygulanan Johnson&Johnson, Pfizer-BioNTech ve Oxford-AstraZeneca a\u015f\u0131lar\u0131ndan herhangi biri uygulanm\u0131\u015f ki\u015filerde \u00e7\u0131\u011f\u0131r a\u00e7\u0131c\u0131 nitelikte enfeksiyonlar\u0131n rapor edildi\u011fini s\u00f6yl\u00fcyor. Haberlere g\u00f6re, Hong Kong\u2019da yeni varyant i\u00e7in test sonucu pozitif olan iki yolcu Pfizer ile a\u015f\u0131lanm\u0131\u015ft\u0131. Bu yolculardan birisi G\u00fcney Afrika\u2019dan seyahat etmi\u015fti, bir di\u011feri ise otel karantinas\u0131 s\u0131ras\u0131nda enfekte oldu. Kaynak:<\/strong> https:\/\/www.nature.com\/articles\/d41586-021-03552-w<\/p>\n","protected":false},"excerpt":{"rendered":" Ara\u015ft\u0131rmac\u0131lar h\u0131zl\u0131 yay\u0131lan koronavir\u00fcs varyant\u0131n\u0131n, COVID-19 a\u015f\u0131lar\u0131n\u0131n etkinli\u011fine kar\u015f\u0131 bir tehdit te\u015fkil edip etmedi\u011fini belirlemek i\u00e7in h\u0131zla \u00e7al\u0131\u015f\u0131yorlar. G\u00fcney Afrika\u2019daki ara\u015ft\u0131rmac\u0131lar, COVID-19 hastal\u0131\u011f\u0131na neden olan SARS-CoV-2 koronavir\u00fcs\u00fcn\u00fcn yeni varyant\u0131n\u0131n endi\u015fe veren y\u00fckseli\u015fini g\u00f6zlemleyebilmek i\u00e7in h\u0131z kesmeden \u00e7al\u0131\u015f\u0131yorlar. Yeni varyant, Delta da dahil olmak \u00fczere, di\u011fer varyantlarda bulunan \u00e7ok say\u0131da mutasyonu da bar\u0131nd\u0131r\u0131yor ve G\u00fcney Afrika\u2019da […]<\/p>\n","protected":false},"author":1191,"featured_media":52985,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[19,21,4696],"tags":[5848,8111,640,8112],"class_list":["post-52983","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-bilim-gundemi","category-biyoloji","category-tip","tag-covid-19","tag-omicron","tag-tip","tag-varyant"],"acf":[],"aioseo_notices":[],"aioseo_head":"\n\t\t\n\t\n\t\n\t\n\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t
\nAra\u015ft\u0131rmac\u0131lar, B.1.1.529\u2019u Botsvana\u2019dan al\u0131nan genom dizileme verilerinde tespit etti. Varyant, konak h\u00fccreleri tan\u0131yan ve v\u00fccudun ba\u011f\u0131\u015f\u0131kl\u0131k yan\u0131tlar\u0131n\u0131n ana hedefi olan spike proteininde 30\u2019dan fazla de\u011fi\u015fiklik i\u00e7erdi\u011fi i\u00e7in g\u00f6ze \u00e7arpt\u0131. Delta ve Alpha gibi varyantlarda da bulunmu\u015f olan de\u011fi\u015fikliklerin \u00e7o\u011fu, bula\u015f\u0131c\u0131l\u0131\u011f\u0131 artt\u0131rma ve enfeksiyonu bloke eden antikorlardan ka\u00e7ma yetene\u011fi ile ili\u015fkili.
\nG\u00fcney Afrika\u2019n\u0131n Johannesburg\u2019a ev sahipli\u011fi yapan Gauteng eyaletindeki yeni varyant vakalar\u0131nda g\u00f6r\u00fclen keskin y\u00fckseli\u015f de tehlike \u00e7anlar\u0131n\u0131n \u00e7almas\u0131na sebep oldu. Lessells\u2019e g\u00f6re, Kas\u0131m ay\u0131nda vakalar, \u00f6zellikle okullarda ve gen\u00e7ler aras\u0131nda h\u0131zla artt\u0131. KwaZulu-Natal \u00dcniversitesi\u2019nde biyoinformatik\u00e7i olan Tulio de Oliveira liderli\u011findeki bir ekip taraf\u0131ndan yap\u0131lan genom sekanslama ve di\u011fer genetik analizler, B.1.1.529 varyant\u0131n\u0131n, Gauteng\u2019te 12 ve 20 Kas\u0131m aras\u0131nda toplanan ve analiz edilen 77 vir\u00fcs \u00f6rne\u011finin tamam\u0131ndan sorumlu oldu\u011funu g\u00f6sterdi. Y\u00fczlerce \u00f6rne\u011fin analizi hala devam etmekte.
\nLessells; varyant\u0131n, genom sekanslamadan daha h\u0131zl\u0131 sonu\u00e7 veren genotipleme testleri ile tespit edilmesini sa\u011flayan bir spike protein mutasyonunu bar\u0131nd\u0131rd\u0131\u011f\u0131n\u0131 s\u00f6yledi. Bu testlerden elde edilen \u00f6n kan\u0131tlar, B.1.1.529\u2019un Gauteng\u2019ten epeyce uza\u011fa yay\u0131ld\u0131\u011f\u0131n\u0131 g\u00f6steriyor. Lessells, \u201cBu sonu\u00e7lar, varyant\u0131n \u00fclkede oluk\u00e7a yayg\u0131n bir \u015fekilde dola\u015f\u0131mda olabilece\u011fi endi\u015fesini veriyor\u201d diye ekledi.<\/p>\n
\nAra\u015ft\u0131rmac\u0131lar, B.1.1.529\u2019un te\u015fkil etti\u011fi tehdidi anlamak i\u00e7in varyant\u0131n G\u00fcney Afrika ve \u00f6tesine yay\u0131lmas\u0131n\u0131 yak\u0131ndan takip ediyor olacaklar. G\u00fcney Afrika\u2019daki ara\u015ft\u0131rmac\u0131lar, 2020 y\u0131l\u0131n\u0131n sonlar\u0131nda G\u00fcney Afrika\u2019da tan\u0131mlanan Beta varyant\u0131n\u0131 h\u0131zl\u0131 bir \u015fekilde incelemek i\u00e7in t\u00fcm \u00e7abalar\u0131n\u0131 seferber etmi\u015flerdi ve \u015fimdi benzer bir \u00e7aba B.1.1.529\u2019u incelemek i\u00e7in ortaya konulmaya ba\u015flad\u0131.
\nBeta varyant\u0131n\u0131n ba\u011f\u0131\u015f\u0131kl\u0131k sisteminden ka\u00e7ma yetene\u011fiyle ilgili ilk verilerin baz\u0131lar\u0131n\u0131 sa\u011flayan Moore\u2019un ekibi, B.1.1.529 varyant\u0131 \u00fczerinde \u00e7al\u0131\u015fmaya ba\u015flad\u0131 bile. Vir\u00fcs\u00fcn di\u011fer ba\u011f\u0131\u015f\u0131kl\u0131k yan\u0131tlar\u0131ndan ka\u00e7ma yetene\u011fiyle birlikte enfeksiyon engelleyici antikorlardan da ka\u00e7ma yetene\u011fini test etmeyi planl\u0131yorlar. Varyant, antikorlar\u0131n tan\u0131d\u0131\u011f\u0131 ve olanak dahilinde antikorlar\u0131n g\u00fcc\u00fcn\u00fc azaltan spike proteininde \u00e7ok say\u0131da mutasyon bar\u0131nd\u0131r\u0131yor. Moore, \u201cBildi\u011fimiz \u00e7o\u011fu mutasyon problem yarat\u0131yor, ancak \u00e7ok daha fazlas\u0131 muhtemelen ba\u011f\u0131\u015f\u0131kl\u0131k sisteminden daha \u00e7ok ka\u00e7\u0131nma yetene\u011fine katk\u0131da bulunuyor gibi g\u00f6r\u00fcn\u00fcyor\u201d diyor. Moore ek olarak, bilgisayar modellemesinden, B.1.1.529\u2019un ba\u011f\u0131\u015f\u0131kl\u0131k sisteminin T h\u00fccreleri ad\u0131 verilen ba\u015fka bir bile\u015feni taraf\u0131ndan sa\u011flanan ba\u011f\u0131\u015f\u0131kl\u0131\u011f\u0131 atlatabilece\u011fine dair ipu\u00e7lar\u0131 bile oldu\u011funu s\u00f6yl\u00fcyor. Ekibi ilk sonu\u00e7lar\u0131n\u0131 iki hafta i\u00e7inde almay\u0131 umut ediyor.<\/p>\n
\nLessells, G\u00fcney Afrika\u2019daki ara\u015ft\u0131rmac\u0131lar\u0131n, B.1.1.529\u2019un di\u011fer varyantlar\u0131n sebep oldu\u011fundan daha \u015fiddetli ya da daha hafif hastal\u0131\u011fa neden olup olmad\u0131\u011f\u0131n\u0131 da inceleyeceklerini s\u00f6yl\u00fcyor ve \u201cKu\u015fkusuz, kilit soru, hastal\u0131\u011f\u0131n ciddiyetine y\u00f6neliyor\u201d diye ekliyor.
\nAra\u015ft\u0131rmac\u0131lar, B.1.1.529 varyant\u0131n\u0131n G\u00fcney Afrika \u00f6tesinde yaratt\u0131\u011f\u0131 tehdidin \u015fimdiye kadar net olmaktan uzak oldu\u011funu s\u00f6yl\u00fcyor. Moore, varyant\u0131n Delta varyant\u0131ndan daha bula\u015f\u0131c\u0131 olup olmad\u0131\u011f\u0131n\u0131n da belirsiz oldu\u011funu ve sebebinin de G\u00fcney Afrika\u2019daki COVID vakalar\u0131n\u0131n d\u00fc\u015f\u00fckl\u00fc\u011f\u00fc oldu\u011funu s\u00f6yl\u00fcyor. \u201cBir durgunluk i\u00e7erisindeyiz\u201d diye ekliyor. Katzourakis, Delta vakalar\u0131n\u0131n olduk\u00e7a yayg\u0131n oldu\u011fu \u00fclkelerin B.1.1.529 belirtilerini izlemesi gerekti\u011fini s\u00f6yl\u00fcyor ve \u201cBu vir\u00fcs\u00fcn rekabet ba\u015far\u0131s\u0131 a\u00e7\u0131s\u0131ndan ne yapt\u0131\u011f\u0131n\u0131 ve yayg\u0131nl\u0131\u011f\u0131n\u0131n art\u0131p artmayaca\u011f\u0131n\u0131 g\u00f6rmemiz gerekiyor\u201d diye ekliyor.<\/p>\n