Oxford–AstraZeneca COVID-19 vaccine

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Oxford AstraZeneca COVID-19 vaccine AZD1222 - 4

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Oxford AstraZeneca vaccine (Indian version) 2021 C

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File:2021-04-26-DRTUMPET AstraZeneca COVID-19 vaccine 6SEC.webm Oxford–AstraZeneca COVID-19 vaccine

The Oxford–AstraZeneca COVID-19 vaccine, also known as AZD1222, is a COVID-19 vaccine developed by Oxford University in collaboration with the pharmaceutical company AstraZeneca. It is a viral vector vaccine that uses a modified chimpanzee adenovirus to deliver the genetic code for the SARS-CoV-2 spike protein into human cells, prompting an immune response.

Development

The development of the Oxford–AstraZeneca COVID-19 vaccine began in early 2020, shortly after the COVID-19 pandemic was declared. Researchers at the University of Oxford's Jenner Institute and the Oxford Vaccine Group led the initial research. The vaccine was developed using a recombinant DNA technology that had been previously used in the development of vaccines for other diseases.

Clinical Trials

The vaccine underwent several phases of clinical trials to assess its safety and efficacy. Phase I/II trials were conducted in the United Kingdom, followed by larger Phase III trials in multiple countries, including the United States, Brazil, and South Africa. The trials demonstrated that the vaccine was effective in preventing symptomatic COVID-19 and had a good safety profile.

Approval and Distribution

The Oxford–AstraZeneca COVID-19 vaccine received its first emergency use authorization in the United Kingdom in December 2020. It was subsequently approved for use in many other countries around the world. The vaccine is distributed under the brand names Vaxzevria and Covishield, depending on the region.

Mechanism of Action

The vaccine uses a non-replicating viral vector derived from a modified chimpanzee adenovirus called ChAdOx1. This vector carries the genetic code for the SARS-CoV-2 spike protein. Once administered, the vector enters human cells and instructs them to produce the spike protein, which triggers an immune response. This response includes the production of antibodies and T cells that can recognize and neutralize the actual virus if the person is exposed to it in the future.

Efficacy and Safety

Clinical trials and real-world data have shown that the Oxford–AstraZeneca COVID-19 vaccine is effective in preventing COVID-19, particularly severe disease and hospitalization. Common side effects include pain at the injection site, fatigue, headache, and mild fever. Rare but serious side effects, such as thrombosis with thrombocytopenia syndrome (TTS), have been reported, leading to some countries recommending age-specific usage guidelines.

Global Impact

The Oxford–AstraZeneca COVID-19 vaccine has played a significant role in the global fight against the COVID-19 pandemic. It is one of the most widely distributed vaccines, particularly in low- and middle-income countries, due to its lower cost and easier storage requirements compared to some other COVID-19 vaccines.

See Also

• COVID-19 pandemic
• COVID-19 vaccine
• Pfizer–BioNTech COVID-19 vaccine
• Moderna COVID-19 vaccine
• Johnson & Johnson COVID-19 vaccine