Five things to know about the As vaccine …

The covid-19 vaccine developed by Britain’s AstraZeneca / Oxford, whose use in Denmark suspended as a precaution after coagulation problems in patients, is cheap and easy to store, but in its short history it has accumulated different controversies. Here are some of its main features:

This vaccine was developed by researchers at the University of Oxford in collaboration with the British laboratory AstraZeneca.

It is a “viral vector” vaccine: is based on another virus (a chimpanzee adenovirus) that has been weakened and genetically modified to prevent the coronavirus from reproducing in the human body.

The way it introduces genetic material into cells, instructing them to attack SARS-CoV-2, has been evaluated as “Trojan horse”.

The AstraZeneca / Oxford vaccine has the advantage of being cheap (around 2.5 euros or 3 dollars per dose, with variations depending on local production costs). AstraZeneca has promised to sell it for no profit.

Too it is easy to store: it can be stored at the temperature of a refrigerator, between 2 ° C and 8 ° C, unlike Moderna and Pfizer / BioNTech vaccines, which can only be stored long term at very low temperatures (-20 ° C in the first case and -70 ° C in the second).

This facilitates large-scale vaccination.

• Confusion over its effectiveness

According to the British laboratory, it has a 70% average efficiency (compared to more than 90% for Pfizer / BioNTech and Moderna), a result validated by the scientific journal The Lancet.

In the first published results, from clinical trials prior to their approval, there were variations in efficacy, depending on different doses administered in error, which sowed doubt and provoked criticism, leading the company to carry out additional studies.

Its effectiveness in people over 65 has also been questioned in Europe due to the lack of data, until new information, extracted from the vaccination campaigns of the most advanced countries in this field, comes to reassure in this regard.

Various countries, such as Germany and Italy have finally authorized it for this age group, in the hope of speeding up their vaccination campaigns.

A study carried out by the health authorities of England demonstrated 60 to 73% protection against symptomatic forms of the disease in people over 70 years old, with a single dose.

• Suspicious blood clots

Denmark announced on Thursday that it was suspending use of the AstraZeneca vaccine as a precautionary measure due to concerns about the development of blood clots in vaccinated people.

The Danish health agency stressed that no link had yet been established between the vaccine and these clots.

A spokesperson for AstraZeneca said that “the safety of the vaccine has been extensively studied in phase III clinical trials and peer-reviewed data confirms that the vaccine was generally well tolerated.”

Austria has already announced Monday that it has stopped administering a batch of vaccines produced by the British laboratory, after the death of a 49-year-old nurse. “Serious bleeding disorders” a few days after receiving it.

Other four European countries, Estonia, Lithuania, Latvia and Luxembourg, suspended Immediate vaccination with the doses of this batch, which was delivered to 17 countries and which included one million vaccines.

The The UK regulator, MHRA, was the first to approve its massive use. The country most affected in Europe by covid-19, with 125,000 deaths, has ordered 100 million doses of this vaccine.

Delays in deliveries to European Union countries sparked strong complaints as the British laboratory continued to deliver the promised doses to the UK.

AstraZeneca announced in January that could only deliver a third of the 120 million doses promised initially to the 27 EU Member States in the first quarter.

Italy recently blocked the export of 250,000 doses, citing “persistent shortages” and “supply delays”.

European Commission President Ursula von der Leyen has warned that other countries could block exports. And he claimed that AstraZeneca had delivered “less than 10%” of the doses ordered between December and March.