How much does the first dose of AstraZeneca protect?


Posted: Monday May 31, 2021 10:58 AM

Currently, Spain has four vaccines to deal with the coronavirus: Pfizer, Moderna, Janssen and AstraZeneca. Each has its own characteristics, a different level of efficiency and they are even of different types (for example, in distinguishing viral vector or mRNA).

However, except in the case of the antidote developed by Johnson & Johnson, most injections have the same peculiarity: they require two doses to ensure their maximum level of protection. A fact which has direct repercussions on the management of vaccination, and which requires the maximum from the authorities to balance the delays between puncture and puncture.

However, just because these vaccines need two doses to reach their peak of protection does not mean that being in the middle of the regimen was in vain. Indeed, as health authorities remind us, it is much more beneficial to have at least one dose than to have nothing.

And the results bear witness to this: in the case of the AstraZeneca vaccine, the second dose of which in children under 60 has been in limbo for weeks (it is now possible to receive it on condition of signing a prior consent) already generates about 70% protection at the start of the pattern.

76% efficiency and no signs of hospitalization

Last February, AstraZeneca released some of the most relevant results from its injection in the Phase III investigation. Specifically, the pharmaceutical company detailed that its vaccine “confirms 100% protection against disease” in situations of maximum severity, reduces hospitalizations and is essential for preventing death.

In this sense, one of the most interesting findings of the study revolves around the first dose. According to AstraZeneca, the vaccine now called Vaxzevria is 76% effective from its first puncture. Likewise, the data showed that positive PCR test records were reduced by 67% (CI: 49%, 78%) after a single dose, and by 50% (CI: 38% to 59%). “This supports a substantial impact on the transmission of the virus,” the company writes.

Indeed, one dose reduces hospitalizations, complications of the virus, deaths and even transmission. A fact that has also been collected by a prestigious scientific journal, The Lancet, whose studies determine that the immunogenicity and effectiveness of the vaccine are still present when first used.

“Exploratory analyzes have shown that the efficacy of the vaccine after a single standard dose of the vaccine from day 22 to day 90 after vaccination is 76.0%”, published by scientific experts, in agreement with the data provided by AstraZeneca, the same as Health referred to when considering leaving the population with a single dose.

Nevertheless, the pharmacist recalls that this efficiency increases to 82% with the second dose. In any case, pharmaceutical companies point out that the greatest asset of the vaccine is not to prevent the transmissibility of the disease (despite the fact that they succeed), but to reduce deaths and complications from the virus. Thus, the studies are clear: the injection of vaccine is a vital insurance.

Back to top button