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Vashandi vehutano vakaita ongororo yakakura vachishandisa kukurumidza kuongorora antigen pachikoro muFrance.Mufananidzo wechikwereti: Thomas Samson/AFP/Getty
Sezvo huwandu hwenyaya dzekoronavirus muUK dzakawedzera kutanga kwa2021, hurumende yakazivisa shanduko yemutambo mukurwisa COVID-19: mamirioni ezvakachipa, nekukurumidza hutachiona bvunzo.Musi wa10 Ndira, yakataura kuti ichasimudzira bvunzo idzi munyika yese, kunyangwe kune vanhu vasina zviratidzo.Miedzo yakafanana ichaita basa rakakosha muchirongwa cheMutungamiriri wenyika, VaJoe Biden, chekuve nedenda riri kunetsa muUnited States.
Miyedzo yekukurumidza iyi inowanzo sanganisa mhino kana huro swab nemvura papepa pepa kudzorera mhinduro mukati mehafu yeawa.Bvunzo idzi dzinonzi bvunzo dzehutachiona, kwete bvunzo dzehutachiona.Ivo vanogona kungoona yakakwira hutachiona, saka vanozopotsa vanhu vazhinji vane yakaderera SARS-CoV-2 hutachiona mazinga.Asi tarisiro ndeyekuti vachabatsira kuchengetedza denda iri nekukasira kuziva vanhu vanonyanya kutapurira, zvikasadaro vanogona kuparadzira hutachiona vasingazive.
Zvisinei, sezvo hurumende yakazivisa gadziriro yacho, gakava rehasha rakatanga.Mamwe masayendisiti ari kufadzwa neBritish nzira yekuyedza.Vamwe vanoti bvunzo idzi dzichapotsa hutachiona hwakawandisa zvekuti kana hukapararira kusvika kumamiriyoni, kukuvadza kwavangakonzeresa kunopfuura kukuvadza.Jon Deeks, uyo anoita basa rekuyedza nekuongorora paYunivhesiti yeBirmingham kuUnited Kingdom, anotenda kuti vanhu vazhinji vanogona kurerutswa pabvunzo dzisina kunaka vochinja maitiro avo.Uye, akadaro, kana vanhu vakagadzirisa bvunzo ivo pachavo, pachinzvimbo chekuvimba nenyanzvi dzakadzidziswa, bvunzo idzi dzinopotsa hutachiona hwakawanda.Iye nemumwe wake wekuBirmingham Jac Dinnes (Jac Dinnes) masayendisiti, uye vanotarisira kuti vanoda data rakawanda pabvunzo dzekukurumidza coronavirus dzisati dzashandiswa zvakanyanya.
Asi vamwe vaongorori vakakurumidza kurwisa, vachiti bvunzo yacho inogona kukuvadza haina kunaka uye "haina basa" (ona go.nature.com/3bcyzfm).Pakati pavo ndiMichael Mina, chiremba wechirwere chechirwere paHarvard TH Chan Chikoro chePublic Health muBoston, Massachusetts, uyo akati gakava iri rinononotsa mhinduro inodiwa padenda iri.Iye akati: "Tichiri kutaura kuti hatina data rakakwana, asi tiri pakati pehondo-maererano nenhamba yenyaya, hatisi kuzonyanya kuipa kupfuura chero nguva."
Chinhu chimwe chete masayendisiti anobvumirana nacho ndechekuti panofanirwa kuve nekutaurirana kwakajeka pamusoro pekuti bvunzo yekukurumidza chii uye kuti mhedzisiro yakaipa inorevei.Mina akati, "Kukandira maturusi kune vanhu vasingazive mashandisirwo ipfungwa yakaipa."
Zvakaoma kuwana ruzivo rwakavimbika rwekukurumidza bvunzo, nekuti-inenge muEurope-zvigadzirwa zvinogona kutengeswa zvichibva pane yekugadzira data pasina yakazvimirira kuongororwa.Iko hakuna chiyero cheprotocol yekuyera mashandiro, saka zvakaoma kuenzanisa ma assays uye kumanikidza nyika yega yega kuita ongororo yayo.
"Uku ndiko kumadokero kwekuongorora," akadaro Catharina Boehme, CEO weInnovative New Diagnostics Foundation (FIND), sangano risingabatsiri muGeneva, Switzerland iro rakaongorora zvakare nekuenzanisa akawanda eCCIDID-19 Analysis nzira.
Muna Kukadzi 2020, FIND yakatanga basa rekuda kuongorora mazana emhando dzebvunzo dzeCCIDID-19 mumiedzo yakajairwa.Hwaro hunoshanda neWorld Health Organisation (WHO) uye masangano ekutsvagisa epasirese kuti aedze mazana emakoronavirus samples uye kuenzanisa kuita kwavo neaya akawanikwa vachishandisa yakanyanya kupfava polymerase chain reaction (PCR) tekinoroji.Iyo tekinoroji inotarisa chaiwo hutachiona hwemajini sequences mumasample anotorwa kubva mumhuno kana pahuro yemunhu (dzimwe nguva mate).PCR-yakavakirwa bvunzo inogona kudzokorora yakawanda yeiyi genetic zvinhu kuburikidza neakawanda kutenderera kwekusimudzira, saka vanogona kuona huwandu hwekutanga hweparvovirus.Asi zvinogona kutora nguva uye zvinoda vashandi vakanyatsodzidziswa uye zvinodhura zvemurabhoritari (ona "Mashandiro Ekuongorora COVID-19").
Yakachipa, inokurumidza bvunzo inogona kushanda nekuona chaiwo mapuroteni (akabatanidzwa anonzi maantigens) pamusoro peSARS-CoV-2 zvimedu.Aya "ekukurumidza antigen bvunzo" haakudze zviri mukati memuenzaniso, saka hutachiona hunogona kungoonekwa kana hutachiona hwasvika pakakwirira mumuviri wemunhu-panogona kunge paine zviuru zvemakopi ehutachiona pamillilita yesampuli.Kana vanhu vachinyanya kutapukira, hutachiona hunowanzosvika pamazinga aya panguva yekutanga kwezviratidzo (ona "Bata COVID-19".
Dinnes akataura kuti data remugadziri pabvunzo senitivity rinonyanya kubva mukuongororwa kwemurabhoritari muvanhu vane zviratidzo zvine huwandu hwehutachiona.Mumiyedzo iyoyo, miyedzo mizhinji yekukurumidza yairatidzika kuva yakaoma zvikuru.(Izvo zvakare zvakanyatsojeka: hazvikwanisi kupa mhedzisiro yenhema-yakanaka.) Zvisinei, migumisiro yekuongorora yenyika chaiyo inoratidza kuti vanhu vane hutachiwana hushoma vanoratidza kushanda kwakasiyana.
Chiyero chehutachiona mumuenzaniso chinowanzoyerwa maererano nehuwandu hwePCR amplification cycles inodiwa pakuona hutachiona.Kazhinji, kana ingangoita makumi maviri neshanu PCR amplification cycles kana zvishoma zvichidikanwa (inonzi cycle cycle, kana Ct, yakaenzana kana isingasviki makumi maviri neshanu), ipapo mwero wehutachiona hwehupenyu hunoonekwa sepamusoro, zvichiratidza kuti vanhu vanogona kutapukira-kunyangwe zvisati zvadaro. zviri pachena kuti vanhu vane kana kuti havana nhanho yakakosha yekutapukira.
Muna Mbudzi gore rapfuura, hurumende yeBritain yakaburitsa zvakabuda muzvidzidzo zvekutanga zvakaitwa kuPorton Down Science Park neOxford University.Zvose zvigumisiro zvisati zvave zvichiongororwa nevezera zvakadhindwa paIndaneti musi waJanuary 15. Izvi zvinoratidza kuti kunyange zvazvo miedzo yakawanda yeantigen (kana kuti "lateral flow") "haisasviki pamwero unodiwa kuti vanhu vakawanda vaendeswe," mu miedzo yemurabhoritari, 4 mhando dzemhando dzaive neCt values kana yakaderera 25. FIND kuongororwazve kweakawanda ekukurumidza test kits kazhinji inoratidzawo kuti kunzwa kune aya mazinga ehutachiona i90% kana kupfuura.
Sezvo huwandu hwehutachiona hunodonha (kureva, kukosha kweCt kukwira), kukurumidza kuongororwa kunotanga kupotsa hutachiona.Masayendisiti kuPorton Down akatarisisa zvakanyanya kune bvunzo dzeInnova Medical muPasadena, California;hurumende yeBritain yakashandisa mari inodarika mazana masere emamiriyoni emadhora (madhora bhiriyoni) kuraira bvunzo idzi, chikamu chakakosha chehurongwa hwayo hwekudzikisa kupararira kwegoronavirus.PaCt level ye25-28, kunzwisiswa kwekuedzwa kunoderedzwa kusvika ku88%, uye nokuda kweCt level ye28-31, kuedza kunoderedzwa kusvika ku76% (ona "Rapid Test Inowana High Viral Load").
Kusiyana neizvi, muna Zvita, Abbott Park, Illinois, Abbott Laboratories yakaongorora BinaxNOW yekukurumidza bvunzo nemhedzisiro isina kunaka.Chidzidzo ichi chakaedza vanhu vanopfuura zviuru zvitatu nemazana matatu muSan Francisco, California, uye vakawana 100% senitivity yemasampuli ane Ct mazinga ari pasi pe30 (kunyangwe munhu ane hutachiona asina kuratidza zviratidzo)2.
Nekudaro, akasiyana calibrated PCR masisitimu anoreva kuti Ct mazinga haagone kuenzaniswa zviri nyore pakati pemarabhoritari, uye hazviwanzo kuratidza kuti huwandu hwehutachiona mumasampuli hwakafanana.Innova akataura kuti UK neUS zvidzidzo zvakashandisa akasiyana PCR masisitimu, uye kuti chete kuenzanisa kwakananga pane imwecheteyo system kwaizoshanda.Vakataura nezvemushumo wehurumende yeBritain yakanyorwa nemasayendisiti ePorton Down mukupera kwaZvita iyo yakaisa bvunzo yeInnova kurwisa Abbott Panbio bvunzo (yakafanana neBinaxNOW kit inotengeswa naAbbott muUnited States).Mumasamples anongodarika makumi maviri ane Ct level iri pasi pe27, ese masamples akadzosa 93% positive results (ona go.nature.com/3at82vm).
Kana tichifunga nezveyedzo yeInnova bvunzo pazviuru zvevanhu muLiverpool, England, iwo nuances maererano neCt calibration aikosha, izvo zvakangoratidza zvikamu zviviri muzvitatu zvemhosva dzine Ct mazinga ari pasi pemakumi maviri neshanu (ona go.nature.com) /3tajhkw).Izvi zvinoratidza kuti bvunzo idzi dzakapotsa chikamu chimwe muzvitatu chezviitiko zvingangotapukira.Nekudaro, zvino zvinotendwa kuti murabhoritari inogadzira sampuli, kukosha kweCt yemakumi maviri neshanu yakaenzana neiyo yakaderera hutachiona nhanho mune mamwe marabhoritari (zvichida yakaenzana neCt yemakumi matatu kana kupfuura), akadaro Iain Buchan, muongorori muHutano. uye Informatics kuAmerican University.Liverpool, yakatungamira kutongwa.
Zvisinei, mashoko acho haana kunyatsozivikanwa.Dix akataura kuti kuyedza kwakaitwa neYunivhesiti yeBirmingham muna Zvita yaive muenzaniso wekuti bvunzo dzakakurumidza sei kupotsa hutachiona.Kupfuura 7,000 asymptomatic vadzidzi ikoko vakatora Innova bvunzo;2 chete vakaongororwa.Nekudaro, apo vaongorori vekuyunivhesiti pavakashandisa PCR kutarisa zvakare gumi muzana yemasampuli asina kunaka, vakawana vamwe vadzidzi vatanhatu vane hutachiona.Zvichienderana nereshiyo yemasampuli ese, bvunzo inogona kunge yakapotsa vadzidzi makumi matanhatu vane hutachiona3.
Mina akati vadzidzi ava vane hutachiwana hushoma, saka havatapurirane nenzira ipi zvayo.Dix anotenda kuti kunyangwe vanhu vane mwero wakaderera wehutachiona vangave vari mumashure ekuderera kwehutachiona, vanogona kunge vari kuwedzera kutapukira.Chimwe chinhu ndechekuti vamwe vadzidzi havaite zvakanaka mukuunganidza masampuli e swab, saka hapana akawanda utachiona matumbu anogona kupasa bvunzo.Anonetsekana kuti vanhu vachatenda zvisirizvo kuti kupasa bvunzo dzisina kunaka kunogona kuve nechokwadi chekuchengetedza kwavo-chokwadi, bvunzo yekukurumidza ingori snapshot inogona kunge isingatapukirwe panguva iyoyo.Deeks akati chirevo chekuti kuyedzwa kunogona kuita kuti nzvimbo yebasa ive yakachengeteka haisi iyo nzira chaiyo yekuzivisa veruzhinji nezvekuita kwayo.Iye akati: "Kana vanhu vakanzwisisa zvisiri izvo nezvekuchengetedza, vanogona kuparadzira hutachiona uhu."
Asi Mina nevamwe vakati vatyairi veLiverpool vakayambira vanhu kuti vasadaro uye vakaudzwa kuti vanogona kuramba vachiparadzira hutachiona mune ramangwana.Mina akasimbisa kuti kugara uchishandiswa kuyedza (senge kaviri pasvondo) ndiyo kiyi yekuita kuti bvunzo dzishande kuti dzive nedenda.
Dudziro yemhedzisiro yebvunzo haibvi chete pakurongeka kwebvunzo, asiwo pamukana wekuti munhu atove neCCIDID-19.Zvinoenderana nehuwandu hwehutachiona munzvimbo yavo uye kana vachiratidza zviratidzo.Kana munhu anobva kunzvimbo ine yakakwira COVID-19 level aine zviratidzo zvechirwere ichi uye akawana mhedzisiro yakaipa, inogona kunge isiri yenhema uye inoda kunyatsotariswa uchishandisa PCR.
Vatsvakurudzi vanopokanawo kana vanhu vachifanira kuzviedza (kumba, kuchikoro kana kubasa).Kuita kwebvunzo kunogona kusiyana, zvichienderana nekuti muongorori anounganidza sei swab uye anogadzirisa sampu.Semuyenzaniso, vachishandisa bvunzo yeInnova, masainzi emurabhoritari asvika pakunzwisiswa kunosvika 79% pamasampuli ese (kusanganisira masamples ane hutachiwana hushoma), asi veruzhinji vakazvidzidzisa vanongowana kunzwa kwe58% (ona “Kurumidza Muedzo: Yakakodzera imba here?") -Deeks anotenda kuti uku kudonha kwekunetseka1.
Zvakangodaro, muna Zvita, iyo British drug regulatory agency yakabvumidza kushandiswa kweInnova yekuyedza tekinoroji mumba kuona hutachiona muvanhu vasina asymptomatic.Mutauriri weDHSC akatsinhira kuti zviratidzo zvebvunzo idzi zvakabva kuNational Health Service yenyika, yakagadzirwa nebazi rezveutano nekugarisana kwevanhu (DHSC), asi yakatengwa kuInnova ndokugadzirwa nekambani yekuChina yeXiamen Biotechnology Co., Ltd. bvunzo inoshandiswa nehurumende yeBritish yakaongororwa zvine mutsindo nemasayendisiti anotungamira eBritish.Izvi zvinoreva kuti vane chokwadi, vanovimbika, uye vanokwanisa kunyatsoona varwere veasymptomatic COVID-19. "Mutauriri akadaro mukutaura.
Chidzidzo cheGerman4 chakaratidza kuti bvunzo dzekuzviitira wega dzinogona kushanda sedzinoitwa nenyanzvi.Chidzidzo ichi hachina kuongororwa nevezera.Ongororo iyi yakaona kuti kana vanhu vakapukuta mhino dzavo vopedza bvunzo isingazivikanwe yakabvumidzwa neWHO, kunyangwe vanhu vachiwanzo tsauka pamirairo yekushandiswa, kunzwa kunenge kwakafanana nekwakawanikwa nenyanzvi.
MuUnited States, iyo Chikafu neDrug Administration (FDA) yakabvumidza zvibvumirano zvechimbichimbi zvekushandisa bvunzo gumi nenhatu, asi imwe chete-yeEllume COVID-19 yekumba bvunzo-inogona kushandiswa kune asymptomatic vanhu.Sekureva kwaEllume, kambani iri muBrisbane, Australia, bvunzo yaona coronavirus muvanhu gumi nevaviri asymptomatic, uye gumi revanhu ava vakaongororwa nePCR.Muna Kukadzi, hurumende yeUS yakazivisa kuti ichatenga 8.5 miriyoni bvunzo.
Dzimwe nyika/matunhu asina zviwanikwa zvakakwana zvekuongororwa kwePCR, senge India, anga achishandisa antigen test kwemwedzi yakawanda, kungowedzera kugona kwavo kwekuyedza.Kunze kwekunetsekana kwechokwadi, mamwe makambani anoita PCR bvunzo achangotanga kuunza dzimwe nzira dzinokurumidza kusvika padiki.Asi hurumende yakaita bvunzo dzakakura dzakati budiriro.Nechiverengero chavagari vapasi chemamiriyoni 5,5, Slovakia ndiyo yakanga iri nyika yokutanga kuedza kuedza vanhu vayo vose vakura.Kuongororwa kwakadzama kwakadzikisa huwandu hwehutachiona neinoda kusvika 60% 5.Nekudaro, bvunzo idzi dzinoitwa pamwe chete nezvirambidzo zvakasimba zvisina kuitwa mune dzimwe nyika uye nerutsigiro rwehurumende rwemari kuvanhu vanovhenekwa kuti vabatsire kugara pamba.Naizvozvo, nyanzvi dzinoti kunyangwe musanganiswa wekuyedza nekudzora uchiita seunodzikisa huwandu hwehutachiona nekukurumidza pane kurambidzwa chete, hazvina kujeka kuti nzira yacho inogona kushanda kumwewo here.Mune dzimwe nyika, vanhu vazhinji vangasada kutora bvunzo nekukurumidza, uye avo vanoongororwa vanogona kushaya chikonzero chekuzviparadzanisa nevamwe.Zvakadaro, nekuti bvunzo dzekukurumidza dzekutengesa dzakachipa-chete madhora mashanu-Mina inoti maguta nematunhu anogona kutenga mamirioni pachidimbu chekurasikirwa kwehurumende kwakakonzerwa nedenda.
Mumwe mushandi wehutano akakurumidza kuyedza mutakuri nemhino pachiteshi chechitima muMumbai, India.Mufananidzo wechikwereti: Punit Parajpe / AFP / Getty
Kurumidza bvunzo dzinogona kunge dzakanyanya kukodzera kune asymptomatic screening mamiriro anosanganisira majeri, pekugara vasina pekugara, zvikoro nemayunivhesiti, uko vanhu vangangoungana zvakadaro, saka chero bvunzo inogona kubata dzimwe nyaya dzehutachiona inobatsira.Asi Deeks anoyambira kusashandisa bvunzo nenzira inogona kuchinja maitiro evanhu kana kuvakurudzira kuti vazorodze nzira dzekuzvidzivirira.Somuenzaniso, vanhu vanogona kududzira migumisiro yakaipa sekushanyira hama dzinokurudzira mumisha inochengetwa vakwegura.
Kusvika pari zvino, muUnited States, nzira dzakakura dzekuyedza dzakatangwa muzvikoro, majeri, nhandare dzendege nemayunivhesiti.Semuenzaniso, kubva muna Chivabvu, Yunivhesiti yeArizona muTucson yave ichishandisa bvunzo yeSofia yakagadzirwa naQuidel muSan Diego, California kuyedza vatambi vayo zuva nezuva.Kubva Nyamavhuvhu, yakaedza vadzidzi kamwechete pamwedzi (vamwe vadzidzi, kunyanya avo vari mudzimba dzekurara vane kuputika, vanoedzwa kakawanda, kamwe chete pasvondo).Parizvino, yunivhesiti yaita bvunzo dzinosvika zana nemakumi mashanu,000 uye haisati yataura kuvhiya kweCCIDID-19 kesi mumwedzi miviri yadarika.
David Harris, muongorori we stem cell anotungamira chirongwa cheArizona chakakura chekuyedza, akati mhando dzakasiyana dzebvunzo dzinoshanda zvakasiyana: kukurumidza bvunzo dzeantigen hadzifanirwe kushandiswa kuongorora kuwanda kwehutachiona muhuwandu.Iye akati: "Kana ukaishandisa sePCR, uchanzwa zvakanyanya.""Asi zvatiri kuedza kuita-kudzivirira kupararira kwehutachiona-antigen bvunzo, kunyanya kana ichishandiswa kakawanda, inoita seinoshanda nemazvo.”
Mudzidzi anobva kuOxford University kuUK akatora bvunzo yekukurumidza antigen yakapihwa neyunivhesiti ndokubhururuka kuenda kuUnited States muna Zvita 2020.
Mapoka mazhinji ekutsvagisa pasirese ari kugadzira nzira dzekuyedza dzinokurumidza uye dzakachipa.Vamwe vari kugadzirisa bvunzo dzePCR kuti vakurumidze maitiro ekusimudzira, asi mazhinji emayedzo aya achiri kuda hunyanzvi hwekushandisa.Dzimwe nzira dzinotsamira panzira inonzi loop-mediated isothermal amplification kana LAMP, inokurumidza kupfuura PCR uye inoda midziyo mishoma.Asi bvunzo idzi hadzina kusimba sePCR-yakavakirwa bvunzo.Gore rakapera, vatsvakurudzi veYunivhesiti yeI Illinois kuUrbana-Champaign vakagadzira yavo yekukurumidza kuongororwa bvunzo: PCR-yakavakirwa bvunzo inoshandisa mate panzvimbo yemhino, kusvetuka nhanho dzinodhura uye dzinononoka.Mari yebvunzo iyi i$10-14, uye mhedzisiro inogona kupihwa mukati memaawa asingasviki makumi maviri nemana.Kunyangwe iyo yunivhesiti ichitsamira pane-saiti marabhoritari kuita PCR, yunivhesiti inogona kuongorora munhu wese kaviri pasvondo.Muna Nyamavhuvhu wegore rapfuura, chirongwa ichi chekuyedza nguva nenguva chakabvumira yunivhesiti kuona kuwedzera kwehutachiona hwekambasi uye nekuidzora zvakanyanya.Mukati mevhiki, nhamba yematare matsva yakaderera ne65%, uye kubva ipapo, yunivhesiti haina kuona huwandu hwakafanana.
Boehme akataura kuti hapana imwe nzira yekuyedza inogona kuzadzisa zvese zvinodiwa, asi nzira yekuyedza inogona kuona vanhu vane hutachiona yakakosha kuchengetedza hupfumi hwenyika hwakavhurika.Iye akati: "Miedzo munhandare dzendege, kumiganhu, kumabasa, zvikoro, makiriniki-muzviitiko zvese izvi, bvunzo dzekukurumidza dzine simba nekuti dziri nyore kushandisa, mutengo wakaderera uye nekukurumidza."Nekudaro, akawedzera Izvo zvakati, mapurogiramu makuru ebvunzo anofanirwa kuvimba nemiedzo yakanakisa iripo.
Iyo EU yazvino yekubvumidza maitiro eCCIDID-19 bvunzo dzekuongorora dzakafanana nedzimwe nzira dzekuongorora, asi kushushikana nezvekuita kwedzimwe nzira dzekuyedza kwakakurudzira kuunzwa kwegwaro idzva Kubvumbi apfuura.Izvi zvinoda kuti vagadziri vagadzire matest kits anogona kuita bvunzo dzeCOVID-19 panguva yazvino yehunyanzvi.Nekudaro, sezvo mhedzisiro yekuyedzwa kunoitwa muyedzo yemugadziri ingave yakasiyana neiri munyika chaiyo, nhungamiro dzinokurudzira kuti nyika dzenhengo dzizvione dzisati dzatanga bvunzo.
Boehme akataura kuti, zvamazvirokwazvo, nyika dzaisazofanira kuona nzira dzese dzekuyera.Marabhoritari nevagadziri pasi rese vachashandisa zvakajairika maprotocol (seaya akagadzirwa neFIND).Iye akati: "Chatinoda inzira yekuyedza uye yekuongorora.""Hazvizove zvakasiyana nekuongorora marapirwo nemishonga."
Nguva yekutumira: Kurume-09-2021