Utengenezaji wa chanjo ya COVID-19 ni kipaumbele cha kimataifa. Katika makala haya, mwandishi amepitia na kutathmini utafiti na maendeleo na hali ya sasa ya maendeleo ya chanjo.
Covid-19 ugonjwa unaosababishwa na virusi vya SARS-CoV-2, umekuwa ukiongezeka kwa kasi katika miezi michache iliyopita duniani kote bila kuona mwisho. Hadi leo, hakuna chanjo imeidhinishwa kutibiwa kwa ugonjwa huu wa kudhoofisha ugonjwa ambayo imeambukiza karibu watu milioni 2 ulimwenguni na kusababisha vifo kati ya 120,000 kati yao (1), idadi ya 6%. Kiwango hiki cha vifo cha 6% ni wastani wa dunia nzima, huku Umoja wa Ulaya ukiwa na kiwango cha vifo cha karibu 10% huku dunia nzima ikiwa na kiwango cha vifo cha karibu 3%. Pia kumekuwa na ahueni ya karibu watu 450,000, idadi ya karibu 23%.
Makampuni ya dawa na teknolojia ya kibayoteknolojia pamoja na vyuo vikuu na taasisi za utafiti duniani kote zinafanya kazi kwa ari kubwa kuendeleza av.mkusanyiko against COVID-19 that could become the saviour of people and prevent them for getting the disease. This article will focus on the concept of vaccine development for viruses, the types (category) of chanjo being developed for COVID-19 by numerous companies, institutes and consortiums around the world who are engaged in its research and development and its present status with emphasis on vaccine candidates that have already entered clinical trials.(1).
Uundaji wa chanjo ya virusi unahusisha utayarishaji wa kibayolojia wa molekuli za virusi zinazojumuisha virusi vilivyopunguzwa, virusi vilivyolemazwa, chembe tupu za virusi au peptidi za virusi na protini peke yake au kwa pamoja, ambazo mara moja hudungwa ndani ya mtu mwenye afya, huchochea mfumo wake wa kinga. kuzalisha kingamwili dhidi ya molekuli za virusi, na hivyo kumlinda mtu wakati maambukizi halisi yanapotokea. Molekuli hizi za virusi na protini zinazofanya kazi kama antijeni, zinaweza kuzalishwa nje (kwenye maabara) au kuzalishwa (kuonyeshwa) ndani ya mtu binafsi (mwenyeji) ili kutoa mwitikio wa kinga. Maendeleo ya kiteknolojia katika uwanja wa teknolojia ya kibayoteknolojia katika muongo mmoja hivi uliopita yamekuwa na jukumu muhimu katika ukuzaji wa chanjo pia, na kusababisha mbinu mpya za utengenezaji wa antijeni za virusi ndani au nje ya mwenyeji, ambazo zimechangia usalama wa chanjo, utulivu na urahisi wa utengenezaji wa kiwango kikubwa.
Aina ya chanjo under development for COVID-19 fall into three broad different categories based on the nature of technology platforms to generate viral antigens (2). The first category comprises of using the live attenuated vaccine (that involves weakening the virulence of SARS-CoV-2 virus) or inactivated virus (in which the inactivation is performed using chemical means) and injecting it in the host to develop an immune response. This category represent the way in which chanjo were made conventionally. The second category in vogue focuses on the production (expression) of viral proteins inside the host (humans) by use of nucleic acids (plasmid DNA and mRNA) and viral vectors (replicating and non-replicating) containing viral genes. These nucleic acids and viral vectors use cellular machinery for the expression of viral proteins within the host upon injection, thereby triggering an immune response. The third category involves development of empty (without genome) viral like particles (VLPs) expressing viral proteins on their surface, use of synthetic peptides (selected parts of viral proteins) and recombinant production of viral proteins as antigens in various expression systems at a large scale outside the human host, and then using them as vaccine candidates alone, or in combination.
As of April 10th 2020, a total of 69 companies, research institutes, universities and/or a consortium of the above (3, 4) are actively engaged at an unparalleled speed in a race against time for the development of COVID-19 vaccine. These companies can be divided into either of the three categories mentioned above based on the technology they are using for COVID-19 vaccine development. Seven of these companies are exploiting the way chanjo are manufactured by the first category and the remaining 62 companies are almost equally divided (30 in the second category which uses plasmid DNA, RNA and replicating and non-replicating viral vectors while 32 in the third category which uses VLPs, peptides and recombinant viral proteins) in terms of the technologies used for vaccine manufacturing for COVID-19. Most of these companies are in exploratory or pre-clinical stages of research and development. However, six of these companies have advanced their candidate chanjo into clinical trials which are listed in Table I (information sourced from references 2-6). All these chanjo fall into the second category.
Utengenezaji wa chanjo ya COVID-19 kulingana na mifumo ya teknolojia inayotumika ni ya 10% ya kitengo cha kwanza na 43.5% ya kitengo cha pili na 46.5% ya kitengo cha tatu mtawalia (Mchoro 1). Kulingana na eneo la kijiografia, Amerika Kaskazini (Marekani na Kanada) inaongoza katika ukuzaji wa chanjo ya COVID-19 kwa asilimia kubwa zaidi ya makampuni (40.5%) ikifuatiwa na Ulaya (27.5%), Asia na Australia (19%) na Uchina (13%). Rejelea Kielelezo 2.
Mchoro 1. Kategoria za utengenezaji wa chanjo ya COVID-19
Table I. COVID-19 chanjo katika majaribio ya kliniki
Kielelezo cha 2. Usambazaji wa kijiografia wa makampuni yanayojishughulisha na utafiti na maendeleo ya chanjo ya COVID-19.
The majority use of categories 2 and 3 in vaccine development for COVID-19 suggests the exploitation of modern state of the art technologies that have led to the ease of manufacturing and might contribute to the safety, stability and effectiveness of vaccine preparations. It is sincerely hoped that the current chanjo in clinical trials and the ones that follow would result in an effective vaccine candidate that can be fast tracked for approval by the regulatory authorities for vaccinating the human population, thereby preventing them from contracting the COVID-19 disease, and overcoming the misery that has been caused by this debilitating disease.
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Marejeo:
1. Worldometer 2020. JANGA LA CORONAVIRUS COVID-19. Ilisasishwa mwisho: Aprili 14, 2020, 08:02 GMT. Inapatikana mtandaoni kwa https://www.worldometers.info/coronavirus/ Ilifikiwa tarehe 13 Aprili 2020.
2. Thanh Le T., Andreadakis, Z., et al 2020. Mandhari ya ukuzaji wa chanjo ya COVID-19. Ilichapishwa tarehe 09 Aprili 2020. Maoni ya Asili DOI ya Ugunduzi wa Dawa: http://doi.org/10.1038/d41573-020-00073-5
3. Taasisi ya Milken, 2020. Kifuatiliaji cha Matibabu na Chanjo ya COVID-19. Inapatikana mtandaoni kwa https://milkeninstitute.org/sites/default/files/2020-03/Covid19%20Tracker_WEB.pdf Ilifikiwa tarehe 13 Aprili 2020.
4. WHO, 2020. DRAFT landscape of COVID-19 candidate chanjo – 20 March 2020. Available online at https://www.who.int/blueprint/priority-diseases/key-action/novel-coronavirus-landscape-ncov.pdf?ua=1 Ilifikiwa tarehe 13 Aprili 2020.
5. Uzingatiaji wa Udhibiti, 2020. Kifuatiliaji cha Chanjo ya COVID-19. Inapatikana mtandaoni kwa https://www.raps.org/news-and-articles/news-articles/2020/3/covid-19-vaccine-tracker Ilifikiwa tarehe 13 Aprili 2020.
6. USNLM 2020. Njia za Kliniki za COVID-19 Zinapatikana mtandaoni kwa https://www.clinicaltrials.gov/ct2/results?cond=COVID-19 Ilifikiwa tarehe 13 Aprili 2020.
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