The vaccine, developed by AstraZeneca and Oxford University, which is considered cheap and simpler, has made a significant contribution to the global fight against the coronavirus pandemic, but it has also been the subject of controversy on several occasions.
–
Here are five important facts about this drug.
Praktiškumas
The main advantages of AstraZeneca and the University of Oxford vaccine are its low cost (around £ 2.5, or € 2.75 per dose) and easy storage conditions.
The product can be stored in a normal refrigerator at 2-8 degrees Celsius, making it ideal for large-scale vaccination programs.
By comparison, Moderna vaccines must be stored at -20 degrees Celsius, and Pfizer and BioNTech products must be stored at -70 degrees Celsius.
According to the US Food and Drug Administration, frozen Pfizer-BioNTech vaccine ampoules can be stored for up to two weeks at a temperature normally maintained in pharmaceutical freezers.
Side effects
Denmark announced on Thursday that it would not use AstraZeneca temporarily as a precautionary measure due to fears that people who had been vaccinated could develop blood clots.
However, the country’s national health agency stressed that it is not yet possible to establish a link between this vaccine and clots.
AstraZeneca itself stated that there was no evidence that its product posed a higher risk of blood clots, adding that this possibility had been “thoroughly investigated in phase III clinical trials”.
Austria on Monday announced that it had stopped vaccinating AstraZeneca with a single batch, killing 49 nurses who had been vaccinated a few days earlier due to blood clotting problems.
Estonia, Lithuania and Luxembourg also suspended vaccination from the same series, which was delivered in 17 countries and contained one million vaccines.
At the time, the European Medicines Agency (EMA) stated that severe allergies should be included in the list of possible side effects of the AstraZeneca vaccine against COVID-19, with a likely link between such cases and vaccination in the United Kingdom.
On Friday, the EEA said it “recommended updating the information on this product to include anaphylaxis and hypersensitivity (allergic reactions) as side effects”.
Delayed delivery
The vaccine was first approved for use in Britain, which ordered 100 million. doses.
However, the delay in delivering the vaccines to the European Union – although at the same time they continued to reach the United Kingdom – has been sharply criticized by the British and Swedish companies.
In January, AstraZeneca announced that it could provide only a third of the 120 million. initially promised to the 27 EU Member States in the first quarter.
That same month, the EU unveiled plans to unilaterally repeal some elements of the “Northern Ireland Protocol” to the Brexit Agreement to prevent vaccines from leaving the bloc. Dissatisfaction from Britain, Ireland and Northern Ireland has forced the EU to soon withdraw a plan that many now see as a diplomatic mistake.
Italy recently blocked a shipment of 250,000 doses of AstraZeneca vaccine to Australia on the grounds of a “persistent” vaccine shortage in Europe and “late delivery”.
Chimpanzees
This vaccine was developed using an adenovirus vector, which means that it used a modified virus that usually infects chimpanzees and adapted it for the production of the SARS-CoV-2 needle protein.
This type of vaccine introduces the immune system to the needle protein to stimulate the human immune system.
Once in human cells, the vaccine should stimulate the production of antibodies that recognize the virus.
According to the medical journal The Lancet, published on December 8, the vaccine is “safe and effective. Only one of the 23,754 volunteers in the vaccine trials had ‘possible side effects’ with the vaccine.
This was a rare neurological case, transverse myelitis, which led to the suspension of trials.
Confusing results
The British laboratory, which published the preliminary results of the study in November, reported that the vaccine had an average effectiveness of 70%, while the Pfizer / BioNTech and Moderna vaccines had an effectiveness of more than 90%.
However, the effectiveness of AstraZeneca was 90 percent in volunteers who received half the dose and a full dose a month later. Less than 62 percent. efficacy was recorded in another group of volunteers who received two full doses of the vaccine with a one-month interval.
Half the dose of the vaccine was accidentally injected into the volunteers, which led to criticism of the company for the reliability of the results and forced additional studies.
Recent studies by health officials in England show that after the first dose of the vaccine, the effectiveness of COVID-19 in the group of people over the age of 70 was between 60 and 73 per cent.
– .
