Coronaviruses ba sababbi ba ne; wadannan sun kai duk wani abu a duniya kuma sun san suna haifar da mura a tsakanin mutane tsawon shekaru. Koyaya, sabon nau'in sa, 'SARS-CoV-2' a halin yanzu yana cikin labarai don haifar Covid-19 annoba sabuwa.
Sau da yawa, sanyi na kowa (wanda ya haifar da coronavirus da kuma sauran ƙwayoyin cuta irin su rhinoviruses) yana rikice da mura.
Mura da mura na gama gari, ko da yake dukkansu suna da alamomi iri ɗaya sun bambanta a ma'anar cewa suna haifar da daban-daban ƙwayoyin cuta gaba ɗaya.
Mura ko mura ƙwayoyin cuta suna da genome mai ɓarna wanda ke haifar da canjin antigenic wanda ke faruwa saboda sake haɗuwa tsakanin ƙwayoyin cuta na wannan nau'in, don haka canza yanayin sunadaran da ke jikin kwayar cutar da ke da alhakin samar da amsawar rigakafi. Wannan yana ƙara rikitarwa da wani abu mai suna antigenic drift wanda ya samo asali daga virus tara maye gurbi (canza a cikinsa DNA tsarin) na tsawon lokaci wanda ke haifar da canje-canje a yanayin sunadaran saman. Duk wannan yana da wuya a samar da maganin rigakafi a kansu wanda zai iya ba da kariya na dogon lokaci. Cutar mura ta ƙarshe ta Mutanen Espanya ta 1918 wacce ta kashe miliyoyin mutane ta kasance ta mura ko mura. virus. Wannan ya bambanta da coronaviruses.
Coronaviruses, wanda ke da alhakin haifar da sanyi na gama gari, a gefe guda, ba su da wani yanki mai ɓarna saboda haka babu canjin antigenic. Sun kasance mafi ƙanƙanta kuma suna haifar da mutuwar mutanen da abin ya shafa. A virulence na karafuranni yawanci yana iyakance ga alamun sanyi kawai kuma da wuya ya sa kowa ya kamu da rashin lafiya. Duk da haka, akwai wasu nau'o'in virulent karafuranni A baya-bayan nan, wato SARS (Severe Acute Respiratory Syndrome) da ya bulla a shekarar 2002-03 a Kudancin China kuma ya yi sanadin kamuwa da cutar guda 8096, wanda ya yi sanadin mutuwar mutane 774 a kasashe 26 da kuma cutar MERS (Middle East Respiratory Syndrome) da ta bayyana bayan shekaru 9 a shekarar 2012. Saudi Arabiya kuma ta haifar da cutar 2494, wanda ya yi sanadiyar mutuwar mutane 858 a cikin kasashe 271. Duk da haka, wannan ya ci gaba da zama mai yaduwa kuma ya ɓace cikin sauri (a cikin watanni 4-6), maiyuwa saboda ƙarancin yanayinsa da/ko ta bin hanyoyin da suka dace don kamuwa da cuta. Don haka, a lokacin, ba a sami buƙatar saka hannun jari mai yawa da samar da allurar rigakafin irin wannan ba coronavirus.
The latest bambancin of coronavirus, novel coronavirus (SARS-CoV-2) da alama yana da alaƙa da SARS da MERS2 wanda ke da kamuwa da cuta sosai a cikin mutane. An gano shi da farko a Wuhan China amma ba da daɗewa ba ya zama annoba kuma ya bazu ko'ina cikin duniya don ɗaukar nau'in cutar. Shin wannan saurin yaduwa a cikin zaɓaɓɓun wuraren ƙasa ne kawai saboda tsananin cutar da kamuwa da cuta sakamakon canje-canje a cikin kundin tsarin halittar gado. virus ko kuma maiyuwa ne saboda rashin ba da agajin gaggawa akan lokaci ta hanyar ba da rahoto ga hukumomin ƙasa da ƙasa da abin ya shafa wanda ya hana matakan ɗaukar lokaci, wanda hakan ya yi sanadiyar mutuwar kusan miliyan guda ya zuwa yanzu da kuma kawo ƙarshen tattalin arzikin duniya.
Wannan shi ne karo na farko a cikin tarihin ɗan adam da akwai coronavirus an ba da rahoton cewa an sami canje-canje a cikin kwayoyin halittar sa wanda ya sanya shi ya zama bambance-bambancen mai saurin kamuwa da cuta, wanda ke da alhakin cutar ta yanzu.
Amma menene zai iya haifar da irin wannan tsattsauran ra'ayi na antigenic wanda ya sa SARS-CoV-2 ta zama mai saurin kamuwa da cuta?
Akwai ra'ayoyi da yawa da ke yawo a cikin al'ummar kimiyya waɗanda ke nuna asalin SARS-CoV-23,4. Magoya bayan asalin ɗan adam virus sun yi imanin cewa canje-canjen kwayoyin halitta da aka gani a cikin SARS-CoV-2 zai ɗauki lokaci mai tsawo don haɓaka ta halitta, yayin da wasu binciken ke jayayya cewa yana iya kasancewa na asali.5 domin idan mutane zasu halicci virus ta hanyar wucin gadi, me yasa za su haifar da wani nau'i mai kyau wanda yake da cutarwa wanda zai iya haifar da cututtuka mai tsanani amma yana da nasaba da kwayoyin halitta da kuma gaskiyar cewa ba a halicce shi ta hanyar amfani da kashin baya na sananne ba. virus.
Kamar yadda zai yiwu, gaskiyar al'amarin ya kasance cewa wani kusan marar lahani virus An yi canje-canjen kwayoyin halitta don canza kanta ta zama SARS/MERS mai sauƙi, kuma a ƙarshe zuwa cikin nau'i mai saurin kamuwa da cuta (SARS-CoV-2) a cikin tsawon shekaru 18-20, ya bayyana sabon abu. Irin wannan tsattsauran raɗaɗin antigenic, wanda ba zato ba tsammani yana da ci gaba a tsakani, zai yi yuwuwar faruwa a cikin al'ada ta al'ada, a cikin dakin gwaje-gwaje na Uwar Duniya, cikin ɗan gajeren lokaci. Ko da gaskiya ne, abin da ya fi daure kai shine matsin muhalli da zai haifar da irin wannan zaɓi a cikin juyin halitta?
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References:
- Padron-Regalado E. Alurar rigakafin SARS-CoV-2: Darussa daga Sauran Cutar Coronavirus [an buga ta kan layi kafin bugawa, 2020 Apr 23]. Kamuwa da Dis Ther. 2020;9(2):1-20. doi: https://doi.org/10.1007/s40121-020-00300-x
- Liangsheng Z, Fu-ming S, Fei C, Zhenguo L. Asalin da Juyin Halitta na 2019 Novel Coronavirus, Cututtukan Cututtuka na Clinical, Juzu'i na 71, Fitowa ta 15, 1 ga Agusta 2020, Shafukan 882–883, DOI:https://doi.org/.1093/cid/ciaa112
- Morens DM, Breman JG, et al 2020. Asalin COVID-19 da Me yasa yake da mahimmanci. Ƙungiyar Amirka ta Magungunan Magunguna da Tsaftar Wuta. Akwai akan layi: 22 ga Yuli 2020. DOI: https://doi.org/10.4269/ajtmh.20-0849
- York A. Novel coronavirus ya tashi daga jemagu? Nat Rev Microbiol 18, 191 (2020). DOI:https://doi.org/10.1038/s41579-020-0336-9
- Andersen KG, Rambaut, A., Lipkin, WI et al. Asalin kusancin SARS-CoV-2. Nat Med 26, 450-452 (2020). DOI: https://doi.org/10.1038/s41591-020-0820-9.
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