Sputnik V: what is the difference between receiving Moderna or AstraZeneca as a second dose

Pablo Sigal

08/04/2021 19:01

• Clarín.com

• Society

Updated 08/04/2021 19:01

The Government finally announced that Argentina

will begin to combine

the Sputnik V vaccine with that of AstraZeneca and Moderna.

It is because the level of antibodies detected is similar to that found with two doses of the Russian vaccine.

In the next few hours this will begin to be implemented throughout the country.

However, the response with one vaccine is not the same as with the other: it is already known that with the American vaccine

the protection will be higher

than with the Oxford one.

On the other hand, Moderna's vaccine is

the first

to be available to begin implementing that combination.

This was confirmed by sources from the Buenos Aires government to

Clarín

.

"The level of immunogenicity with the AstraZeneca vaccine is

statistically similar

to that achieved with the second component of Sputnik V, while with Moderna it is expected to be even higher," they explained.

There has not yet been time to measure the antibodies generated by Moderna's vaccine, but the initial reaction it provoked in the volunteers, in terms of adverse effects - always mild - was superior.

"This

is a sign

that the antibodies it develops are higher," said the sources consulted.

The presumption, based on the available evidence, that Moderna's vaccine performs better,

is consistent with international studies

of combination with another viral vector vaccine.

That is, that of AstraZeneca as the first dose and that of Moderna or Pfizer (both of messenger RNA) as the second.

The Oxford technology is the same as that used by the Russian.

The AstraZeneca vaccine, an alternative to replace the Russian one.

Photo: AFP

The worst performance in the combination trial was the Sinopharm vaccines, which were also part of the Buenos Aires clinical trial.

"The level of antibodies achieved after a first dose of Sputnik

was not significant,

" explained an expert with access to the results of the work.

The trial that was carried out in the City - whose conclusions will be published in a scientific journal - obtained its results by carrying out blood extractions

28 days after

the work with the volunteers began.

"A similar level of antibodies from the point of view of cellular immunity gives us the guideline that the effectiveness of the heterologous vaccination

is equivalent

 to the homologous one."

Two doses of Sputnik V give 92 percent effectiveness.

Based on these results, the City has already announced what this Thursday morning the head of the Buenos Aires Government, Horacio Rodríguez Larreta, will publicly announce: the beginning of the application of

more than 150 thousand doses of Moderna

, which is the remnant that it will be left to the district after vaccinating minors with comorbidities. They expected 30 thousand boys between the ages of 12 and 17 to sign up and only 10 thousand signed up.

Before granting the appointments, they will

send telephone messages

to the people waiting for the second dose of Sputnik to ask them if they agree to receive an alternative vaccine.

In the City, there are

just over 100,000 people

who have already spent 4 months without this supplement.

That is to say that the doses of Moderna would be enough to vaccinate all the laggards of the Russian.

At the national level, there are

 more than a million people

who have already been waiting for a four-month period for the second component of Sputnik, which in principle could be covered by the remaining dose of Moderna, which is

1.7 million

.

That is to say that with that amount the Government would be "up to date", at least with the most delayed.

Regarding the possibility of using AstraZeneca vaccines as second doses, first we must wait

for new batches to arrive in the country

.

The last shipment, of less than a million vaccines, arrived in Argentina the last week of July.

And there are still about

12 million doses to come

for the total of 22.4 million of the signed contract.

Those doses will also have to be used, of course, with those awaiting the second dose of AstraZeneca.

The interval between the first and the second for that brand was set at

two months

.

It will be necessary to see if the amount that arrives in the future will be enough to complete the schemes of the Oxford and, in addition, 

supply the missing

of the second component of the Sputnik V.

If the announcements that were made from Russia in the last hours are fulfilled, during August the production of the second doses of the Russian vaccine would be normalized and they could begin to arrive in greater quantities in Argentina, with which the instance of

having to choose

to whom to allocate the AstraZeneca doses would become abstract.

Moreover, if along with the latter is reflected the other announcement known this week: that the Richmond laboratory would contribute a good part of second doses of Sputnik V. to the cause.

$

Look also

Delta variant: the two faces of its "virulence" and what are the chances of ending up in the hospital

Vaccine combination: what health passport will those who choose to replace the second component of Sputnik have