07/12/2021 8:16 PM
Clarín.com
International
Updated 07/19/2021 9:25 AM
The Covid vaccine emerges as a key step in the tough fight against a pandemic.
Without a doubt,
the best protection shield
.
But while the pigeonholes advance, the spread of new strains, such as Delta, raise questions about the
immunity of vaccines
.
The scientists revealed that the reasons have to do with the fact that it can take several weeks for the body to develop protection against the disease and current vaccines require two doses to reach a high degree of effectiveness.
Doubts arise time and again about the efficacy of each licensed vaccine in the context of a global emergency arising from the SARS-CoV-2 virus.
Vaccination appears as the best shield to protect against coronavirus in the world.
Photo: AFP
But another of the big questions is
how long each vaccine takes to generate immunity against Covid.
.
Sputnik V
The
Russian Sputnik V vaccine
, one of the Argentine bets to advance the immunization process, protects against all known variants of the coronavirus, including the contagious Delta, according to its creator,
Alexandre Guintsbourg, director of the Gamaleya institute
.
In addition, according to a study on their immune response in which 288 people participated, it indicated that 94% showed the presence of antibodies after the first dose.
A flight arrives from Russia to Argentina, loaded with Sputnik V vaccines: Photo: Presidency
In more detail, they clarified that
96% of those under 60 years of age have antibodies 21 days after receiving the first application
.
And the percentage drops to 89% in the elderly.
After adding the dose with the second component of Sputnik V, they generate antibodies in 100% of those vaccinated, said a study by the Serological Studies Platform of the Province of Buenos Aires.
The researchers arrived at these numbers after taking plasma samples from health personnel volunteers before vaccination, 21 days after the first dose and 21 days after the second.
AstraZeneca
The Oxford-AstraZeneca vaccine is effective in people who have not had Covid, and with a wait of about 10 weeks between doses, it is around 80%.
The AstraZeneca / Oxford vaccine (Photo: AFP)
They conclude that
the greatest effectiveness of the AstraZeneca vaccine would be reached 15 days after the second dose
, therefore, between the 10-12 weeks of waiting between the first and the second, plus 15 days, immunity with AstraZeneca would be reached. around
110 days from the start
.
Sinopharm
It was the reports presented by the
Chinese Sinopharm vaccine
laboratory
that made many people question the benefits of the vaccine.
They taught the advisory commission on immunizations of the World Health Organization (WHO) that provides
65% protection in people under 60
to avoid serious illness and complications derived from the coronavirus.
A medical worker holds a package of a Sinopharm vaccine in Beijing, China. Photo: AP
In turn, the preliminary results of Phase III indicated that it provides
79.34%
protection
from 14 days after receiving the second dose
.
Pfizer
The laboratories of
Pfizer and BioNTech
have just announced that they will officially start the procedures before the regulatory entities of the United States and Europe, to obtain the authorization of a third dose of the vaccine against COVID-19, in the face of an apparent decrease in immunity against the Delta variant.
The Covid-19 vaccine from the American pharmaceutical company Pfizer.
Photo: AFP
However, it is known that this vaccine is
the fastest to achieve immunity after receiving the second dose, 21 days after the first
.
Therefore, after the 21 days that must exist between the first and second dose, it will be necessary to
wait another seven to achieve complete immunity:
28 days in total.
The effectiveness indicated in this period reaches 94.6%.
Modern
In the case of those who received the
American Moderna vaccine
(both with or without evidence of previous Covid infection), immunity would be reached
14 days after the second dose
.
Precisely this immunity
would reach 93.6%
and between the first and the second dose, the interval
recommended is 28 days.
For example, only
42 days after the first dose would the person be immunized
.
Immunity with the Moderna vaccine would be achieved 14 days after the second dose.
Photo: Bloomberg
However, as in other cases, studies have shown that after the first dose it already offers high protection.
Janssen of Johnson & Johnson
The Janssen vaccine offered by Johnson & Johnson against the coronavirus
is the only one of all that comes as a single dose
.
After 14 days of the only application in participants without evidence of previous infection, an
efficacy of 66.9%
was observed
.
The studies also noted that it was 82.4% in people 65 years of age or older;
and 100% if you speak of 75 years and up.
While in people from 18 to 64 years old, only 64.2%.
The only single-dose vaccine at Johnson & Johnson's Janssen.
Photo: AFP
The efficacy against severe disease due to Covid-19 was
76.7% at 14 days after vaccination and 85.4% at 28 days
.
Beyond the expectations generated in each case, it was demonstrated in this time of pandemic that today's certainties may turn into doubts tomorrow.
That is why scientific research does not stop,
the new strains put laboratories to the test
in terms of efficacy and immunity period.
Immune reactions that can protect against Covid for years are high hopes, although there are already those who bet on the need in some cases for a
third booster dose
.
Look also
Unusual effect of the Pfizer vaccine: women with larger breasts after the dose against Covid
COVID: a nurse who had the two doses of the Chinese Sinovac vaccine died
COVID: did not want to be vaccinated for fear of side effects and died from the Delta variant
