Interim results from Phase 3 trials in the UK and Brazil showed a vaccine of 704% protection over 20000 volunteers were involved in the trials, half of them in the UK Investigators recorded 30 cases of Covid-19 in people who had two doses of vaccine and 101 in those who received a control bump, which was the case in those who received two full doses Vaccine 62% Protective But it seems to work better when given initially as a half dose followed by a full dose, then the protection increases to 90%

The security analysis comes from a database from 24000 volunteers who have participated in the UK, Brazil and South Africa clinical trials and have been followed up since April, according to the scientists, no serious safety incidents related to the vaccine have been identified which will be comforting as the processes were disrupted after a volunteer entered Britain had gotten sick No details on minor side effects such as arm pain or post-shock fatigue have been released

Older people are most at risk of Covid, so scientists were keen to see a good response in older subjects.Many vaccines for other infections are less effective in older people because the immune system wanes with age However, data from Oxford suggest that younger and older adults experienced a “similar” response

At the heart of Oxford / AstraZeneca’s vaccine is a virus that causes colds in chimpanzees.The chimpanzee virus is modified so that it cannot multiply and cause disease in the body.It is then made with the gene for the coronavirus spike protein loaded, the club-shaped part that punctures the surface of the virus and is used to penetrate human cells

When the vaccine is injected, the chimpanzee virus delivers the coronavirus gene to human cells, which begin to produce the spike protein.These are recognized by the immune system, which produces antibodies and other reactions that can attack the real coronavirus in case the person will become infected in the future

The Oxford vaccine, named ChAdOx1 nCoV-19, is based on a different technology than the two most recent “mRNA” vaccines from Pfizer / BioNTech and Moderna, which both performed well against Covid Regulatory Authorities, but the Oxford Approach has been applied to vaccines that have been safely given to thousands of people of all ages against diseases ranging from TB and malaria to Mers (another coronavirus) and Ebola, for which it is currently used in Uganda and the Democratic Republic of the Congo used Oxford chose the chimpanzee virus because it has the potential to produce a strong immune response, and since it cannot grow in humans, it should be safe

Two other top-of-the-line vaccines from BioNTech (developed with Pfizer) and Moderna (developed with the US National Institute of Allergy and Infectious Diseases) are performing well and achieving an efficacy of, according to interim results from phase 3 human trials over 90% of these are based on technologies that are new to the vaccine field Both use genetic material called mRNA or messenger RNA that tells human cells how to make coronavirus spike proteins The vaccines use lipid nanoparticles to make deliver the mRNA to muscle cells that produce the spike protein and protect the immune system from infection. In principle, mRNA vaccines can be developed faster and more easily made

While BioNTech’s vaccine must be stored at -70 ° C to -80 ° C, making distribution a complex logistical challenge, Moderna vaccine can be refrigerated at 2 ° C to 8 ° C for a month Oxford’s vaccine can also be stored in standard refrigerators, which makes distribution much easier Measles is applied

Oxford vaccine is far cheaper than others that have shown effectiveness AstraZeneca plans to sell Oxford vaccine for $ 3-4 per shot compared to $ 20 for the Pfizer / BioNTech shot and $ 25 for Moderna

AstraZeneca has reached agreements, by next summer 2 billion To administer doses of his vaccine As part of the European Alliance for Inclusive Vaccines, up to 400 million Doses of Oxford Vaccine Shipped to European Nations There are already 4 million doses of Oxford vaccine in the UK with 96 million to come.Other orders include 40 million doses of Pfizer / BioNTech vaccine and 5 million doses of Moderna vaccine

A big question with all coronavirus vaccines is whether they prevent asymptomatic infections, as well as diseases caused by the virus. Reducing asymptomatic infections, if people can spread the virus without knowing they have it, could have a huge impact on it The Oxford data found some evidence of reduced asymptomatic infections in those who received half the dose followed by a full dose later

Nobody knows how long the Oxford vaccine or any other coronavirus vaccine will provide protection.Some vaccines are effective for years, but for obvious reasons it will take longer to confirm

Oxford Vaccine

World News – UK – Oxford AstraZeneca Covid Vaccine: Everything We Know So Far

Source: https://www.theguardian.com/world/2020/nov/23/oxford-astrazeneca-covid-vaccine-everything-we-know-so-far