{"id":62453,"date":"2020-04-14T09:06:01","date_gmt":"2020-04-14T06:06:01","guid":{"rendered":"http:\/\/realitatearutiera.ro\/?p=62453"},"modified":"2020-04-14T09:06:04","modified_gmt":"2020-04-14T06:06:04","slug":"cercetatorii-au-decriptat-in-premiera-traseul-covid-19","status":"publish","type":"post","link":"https:\/\/realitatearutiera.ro\/?p=62453","title":{"rendered":"Cercet\u0103torii au decriptat \u00een premier\u0103 traseul COVID-19"},"content":{"rendered":"\n<p>O echip\u0103 de cercet\u0103tori a reconstruit c\u0103ile evolutive timpurii ale COVID-19 la oameni, pe m\u0103sur\u0103 ce infec\u0163ia cu noul coronavirus s-a extins din Wuhan, China, \u00een Europa \u015fi America de Nord. Harta r\u0103sp\u00e2ndirii \u015fi evolu\u0163iei coronavirusului a fost f\u0103cut\u0103 de cercet\u0103tori de la Universitatea Cambridge, Marea Britanie, \u015fi din Germania, care au folosit tehnici de re\u0163ea genetic\u0103.<\/p>\n\n\n\n<p>Analiz\u00e2nd primele 160 de genomuri complete ale virusului SARS-CoV-2, secven\u0163iate apoi de la pacien\u0163i umani, oamenii de \u015ftiin\u0163\u0103 au trasat o parte din r\u0103sp\u00e2ndirea ini\u0163ial\u0103 a noului coronavirus, prin muta\u0163iile sale, ceea ce creeaz\u0103 filia\u0163ii virale diferite.<\/p>\n\n\n\n<p>\u201eExist\u0103 prea multe muta\u0163ii rapide pentru a urm\u0103ri atent un arbore genealogic al COVID-19. Am folosit un algoritm matematic pentru a vizualiza simultan to\u0163i arborii plauzibili\u201d, a afirmat geneticianul Peter Forster, autorul principal al studiului din cadrul&nbsp;<a href=\"http:\/\/www.cam.ac.uk\/research\/news\/covid-19-genetic-network-analysis-provides-snapshot-of-pandemic-origins\" rel=\"noreferrer noopener\" target=\"_blank\">Universit\u0103\u0163ii din Cambridge<\/a>.<\/p>\n\n\n\n<p>Potrivit doctorului Forster, aceste tehnici sunt folosite \u00een special pentru \u201ecartografierea, prin ADN, a mi\u015fc\u0103rilor popula\u0163iilor umane preistorice\u201d.&nbsp;<\/p>\n\n\n\n<p>\u201eCredem c\u0103 este una dintre primele d\u0103\u0163i c\u00e2nd s-a folosit pentru urm\u0103rirea rutelor de&nbsp;<a href=\"https:\/\/www.descopera.ro\/dnews\/19000038-evolutia-simptomelor-de-coronavirus-si-a-bolii-covid-19-pe-zile\" target=\"_blank\" rel=\"noreferrer noopener\">infec\u0163ie ale unui coronavirus precum COVID-19<\/a>\u201d, a precizat acesta.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">Coronavirusul de tipul \u201eB\u201d, cel mai r\u0103sp\u00e2ndit \u00een&nbsp;Wuhan \u015fi&nbsp;Asia de Est<\/h2>\n\n\n\n<p>Echipa condus\u0103 de geneticianul de la Cambridge a folosit informa\u0163ii din mostre de virus prelevate din \u00eentreaga lume, \u00eentre 24 decembrie 2019 \u015fi 4 martie 2020. Cercetarea a eviden\u0163iat \u201evariante\u201d distincte ale COVID-19, const\u00e2nd \u00een grupuri liniare str\u00e2ns legate \u00eentre ele, pe care le-au denumit \u201eA\u201d, \u201eB\u201d \u015fi \u201eC\u201d.<\/p>\n\n\n\n<p>Forster \u015fi colegii s\u0103i au descoperit c\u0103 tipul de COVID-19 cel mai apropiat de cel descoperit la lilieci este tipul \u201eA\u201d &#8211; \u201egenomul original al virusului uman\u201d- care a fost prezent \u00een Wuhan, dar, spre surprinderea cercet\u0103torilor, nu a fost tipul de virus predominant \u00een ora\u015ful din China.<\/p>\n\n\n\n<p>Au fost observate<a href=\"https:\/\/www.descopera.ro\/stiinta\/18932907-exista-doua-tulpini-ale-coronavirusului-covid-19-care-provoaca-infectii\" target=\"_blank\" rel=\"noreferrer noopener\">&nbsp;versiuni mutante<\/a>&nbsp;ale tipului \u201eA\u201d la americanii despre care s-a raportat c\u0103 au tr\u0103it \u00een Wuhan. Totodat\u0103, un num\u0103r mare de virusuri de tip A au fost g\u0103site la pacien\u0163i din SUA \u015fi Australia.<\/p>\n\n\n\n<figure class=\"wp-block-image\"><img decoding=\"async\" src=\"https:\/\/i1.wp.com\/storage0.dms.mpinteractiv.ro\/media\/401\/321\/5387\/19063542\/3\/noul-coronaviorus-la-microscop-a-niaid-rml-descopera.jpg?w=800&#038;ssl=1\" alt=\"\" data-recalc-dims=\"1\"\/><\/figure>\n\n\n\n<p>Principalul virus din Wuhan a fost tipul \u201eB\u201d, predominant la pacien\u0163ii din Asia de Est. Cu toate acestea, varianta B a virusului nu a c\u0103l\u0103torit mult \u00een afara regiunii, f\u0103r\u0103 muta\u0163ii ulterioare. Potrivit cercet\u0103torilor, a existat \u201erezisten\u0163\u0103\u201d \u00eempotriva acestui tip de coronavirus \u00een afara Asiei de Est.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">Tipul \u201eC\u201d al coronavirusului, r\u0103sp\u00e2ndit \u00een Europa<\/h2>\n\n\n\n<p>Varianta \u201eC\u201d a virusului SARS-CoV-2 este principalul tip de coronavirus din Europa, \u00eent\u00e2lnit la primii pacien\u0163i din Fran\u0163a, Italia, Suedia \u015fi Anglia. Aceast\u0103 variant\u0103 a coronavirusului lipse\u015fte din e\u015fantioanele studiate \u00een China continental\u0103, dar a fost identificat\u0103 \u00een Singapore, Hong Kong \u015fi Coreea de Sud.<\/p>\n\n\n\n<p>Mai mult, noua analiz\u0103 sugereaz\u0103 c\u0103 una dintre primele introduceri ale virusului \u00een Italia a venit prin intermediul primei infec\u0163ii din Germania,&nbsp; documentat\u0103 \u00een 27 ianuarie, iar o alt\u0103 cale de infec\u0163ie timpurie din Italia a fost legat\u0103 de un \u201egrup de Singapore\u201d.<\/p>\n\n\n\n<figure class=\"wp-block-image\"><a href=\"https:\/\/i2.wp.com\/storage0.dms.mpinteractiv.ro\/media\/401\/321\/5387\/19063542\/1\/harta-raspandire-virus.jpg\" target=\"_blank\" rel=\"noreferrer noopener\"><img decoding=\"async\" src=\"https:\/\/i2.wp.com\/storage0.dms.mpinteractiv.ro\/media\/401\/321\/5387\/19063542\/1\/harta-raspandire-virus.jpg?w=800&#038;ssl=1\" alt=\"\" data-recalc-dims=\"1\"\/><\/a><\/figure>\n\n\n\n<p><em>Credit foto: Peter Forster, Lucy Forster, Colin Renfrew, \u015fi Michael Forster<\/em><\/p>\n\n\n\n<p>Mai important, cercet\u0103torii afirm\u0103 c\u0103 tehnicile lor de re\u0163ea genetic\u0103 au urm\u0103rit cu exactitate stabilirea c\u0103ilor de infec\u0163ie: muta\u0163iile \u015fi genealogia viral\u0103 s-au al\u0103turat \u00een punctele dintre cazurile cunoscute de COVID-19.<\/p>\n\n\n\n<p>Astfel, oamenii de \u015ftiin\u0163\u0103 sus\u0163in c\u0103 aceste metode \u201efilogenetice\u201d ar putea fi aplicate la cea mai recent\u0103 secven\u0163iere a genomului coronavirusului, pentru a ajuta la prezicerea viitoarelor puncte fierbin\u0163i de transmitere \u015fi cre\u015ftere a num\u0103rului de cazuri COVID-19, la nivel mondial.<\/p>\n\n\n\n<p>\u201eAnaliza re\u0163elei filogenetice are poten\u0163ialul de a ajuta la identificarea surselor de infec\u0163ie COVID-19 nedocumentate, care pot fi apoi plasate \u00een carantin\u0103 pentru a controla extinderea suplimentar\u0103 a bolii \u00een \u00eentreaga lume\u201d, a afirmat Forster.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">Varianta \u201eA\u201d, reg\u0103sit\u0103 la lilieci \u015fi pangolini, este&nbsp;\u201er\u0103d\u0103cina epidemiei\u201d de coronavirus<\/h2>\n\n\n\n<p>Varianta \u201eA\u201d, cea mai apropiat\u0103 de virusul detectat nu numai la \u200b\u200blilieci, c\u00e2t \u015fi la pangolini, este descris\u0103 de cercet\u0103tori ca fiind \u201er\u0103d\u0103cina epidemiei\u201d de coronavirus. Tipul \u201eB\u201d este derivat din \u201eA\u201d, separat de dou\u0103 muta\u0163ii, \u00een timp ce varianta&nbsp; \u201eC\u201d este catalogat\u0103 de cercet\u0103tori drept o \u201efiic\u0103\u201d a lui \u201eB\u201d.<\/p>\n\n\n\n<p>Cercet\u0103torii afirm\u0103 c\u0103 localizarea variantei \u201eB\u201d \u00een Asia de Est ar putea fi rezultatul unui \u201eefect fondator\u201d: un blocaj genetic care apare atunci c\u00e2nd, \u00een cazul unui virus, un nou tip este stabilit dintr-un grup mic \u015fi izolat de infec\u0163ii.<\/p>\n\n\n\n<figure class=\"wp-block-image\"><img decoding=\"async\" src=\"https:\/\/i1.wp.com\/storage0.dms.mpinteractiv.ro\/media\/401\/321\/5387\/19063542\/4\/noul-coronaviorus-la-microscop-niaid-rml-descopera.jpg?w=800&#038;ssl=1\" alt=\"\" data-recalc-dims=\"1\"\/><\/figure>\n\n\n\n<p>Forster sus\u0163ine, \u00eens\u0103, c\u0103 exist\u0103 o alt\u0103 explica\u0163ie care ar putea fi luat\u0103 \u00een considerare. \u201eVirusul de tipul B din Wuhan ar putea fi adaptat imunologic sau la mediu la o mare parte a popula\u0163iei Asiei de Est. Este posibil s\u0103 aib\u0103 nevoie de muta\u0163ie pentru a dep\u0103\u015fi rezisten\u0163a din afara Asiei de Est. Se pare c\u0103 vedem o rat\u0103 de muta\u0163ie mai lent\u0103 \u00een Asia de Est dec\u00e2t \u00een \u200b\u200balt\u0103 parte, \u00een aceast\u0103 faz\u0103 ini\u0163ial\u0103\u201d, a afirmat cercet\u0103torul.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">Prima infec\u0163ie COVID-19 ar fi ap\u0103rut \u00eentre jum\u0103tatae lui septembrie \u015fi&nbsp;\u00eenceputul lunii decembrie<\/h2>\n\n\n\n<p>Acesta a precizat c\u0103 re\u0163eaua viral\u0103 pe care a detaliat-o este imaginea primelor etape ale epidemiei de coronavirus, \u00eenainte ca \u201etraseele evolutive ale COVID-19 s\u0103 devin\u0103 \u00eentunecate de un num\u0103r mare de muta\u0163ii\u201d.&nbsp;<\/p>\n\n\n\n<p>Forster spune c\u0103 cea mai recent\u0103 cercetare sugereaz\u0103 c\u0103 prima infec\u0163ie cu noul coronavirus \u015fi r\u0103sp\u00e2ndirea COVID-19 \u00een r\u00e2ndul oamenilor a avut loc \u00eentre jum\u0103tatea lunii septembrie \u015fi \u00eenceputul lunii decembrie.<\/p>\n\n\n\n<p>Studiul a fost publicat \u00een jurnalul \u015ftiin\u0163ific&nbsp;<a href=\"http:\/\/www.pnas.org\/content\/early\/2020\/04\/07\/2004999117\" rel=\"noreferrer noopener\" target=\"_blank\"><em>Proceedings of the National Academy of Sciences (PNAS)<\/em><\/a>.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>O echip\u0103 de cercet\u0103tori a reconstruit c\u0103ile evolutive timpurii ale COVID-19 la oameni, pe m\u0103sur\u0103 ce infec\u0163ia cu noul coronavirus<\/p>\n","protected":false},"author":1,"featured_media":62454,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"spay_email":"","footnotes":"","jetpack_publicize_message":""},"categories":[12],"tags":[],"class_list":["post-62453","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-stiri-internationale"],"jetpack_featured_media_url":"https:\/\/i0.wp.com\/realitatearutiera.ro\/wp-content\/uploads\/2020\/04\/NTY3NTRhM2RkOThiNWYyNTVjNjhjMDMyMzAz.thumb_.jpg?fit=780%2C440&ssl=1","jetpack_publicize_connections":[],"jetpack_sharing_enabled":true,"jetpack_shortlink":"https:\/\/wp.me\/p61naM-gfj","jetpack-related-posts":[],"_links":{"self":[{"href":"https:\/\/realitatearutiera.ro\/index.php?rest_route=\/wp\/v2\/posts\/62453","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/realitatearutiera.ro\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/realitatearutiera.ro\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/realitatearutiera.ro\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/realitatearutiera.ro\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=62453"}],"version-history":[{"count":1,"href":"https:\/\/realitatearutiera.ro\/index.php?rest_route=\/wp\/v2\/posts\/62453\/revisions"}],"predecessor-version":[{"id":62455,"href":"https:\/\/realitatearutiera.ro\/index.php?rest_route=\/wp\/v2\/posts\/62453\/revisions\/62455"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/realitatearutiera.ro\/index.php?rest_route=\/wp\/v2\/media\/62454"}],"wp:attachment":[{"href":"https:\/\/realitatearutiera.ro\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=62453"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/realitatearutiera.ro\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=62453"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/realitatearutiera.ro\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=62453"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}