Should the second dose of another vaccine be given or wait? Is it safe to combine vaccines? Can I choose which one to give me? Faced with concerns like these, which in the last week have been gaining ground among a sector of society, specialists seem to agree on the importance of completing immunization schemes “as soon as possible”, whether they are homologous or not.
Based on international and national scientific evidence, last Wednesday the Ministry of Health announced that people who have only received a single dose against Covid will be able to choose between waiting for the second dose of the vaccine that has already been applied or combining schedules to complete as soon as possible its inoculation.
For this, those who have received the first dose of Sputnik V will be able to complete the second with AstraZeneca or Moderna; and those who have a first dose of AstraZeneca will be able to resort to that of Moderna.
The first concern that triggered the announcement among many of the people who have been waiting for three months to complete their immunization schedule was whether to apply the second dose with another vaccine or to wait
All the studies that have been carried out with a combination of vaccines have shown that they are safe and effective: they did not generate adverse effects and the response of the immune system was similar or superior “
Infectious disease doctor
Asked about this point, the infectologist Ricardo Rüttimann, coordinator of the Vaccine Commission of the Argentine Society of Infectious Diseases (SADI), recommended not to postpone the decision.
“In any vaccination campaign one of the most important premises is not to lose opportunities. Therefore, if the person has the possibility of completing the vaccination schedule that began with Sputnik V with AstraZeneca or Moderna, they should do so as soon as possible ”, he said.
Another of the doubts that the possibility of combining vaccines raised among many is whether it is safe to give a second one different from the first and if this does not diminish the effectiveness.
“All the studies that have been carried out on combination vaccines, both in the world and in Argentina, have shown that they are safe and effective; this means that they did not generate adverse effects as long as the response of the immune system was similar or superior to the homologous schemes (two identical vaccines) ”, said the infectologist Elena Obieta.
How important is it to complete the vaccination schedule today? For the clinical doctor Mariana Lestelle it is “essential”.
“Given the appearance of new variants of the virus, and in particular before the Delta variant, which is the one that has generated new outbreaks in the world and which is much more contagious than the original, complete the vaccination schedules, that is, to have the two doses of vaccines, is an essential need. Therefore, faced with the possibility of having a second dose, even if it is different from the first, don’t wait! The priority is to strengthen immunity ”.
“We must not lose opportunities. If a person has the possibility of completing the vaccination schedule that began with Sputnik V with AstraZeneca or Moderna, they should do so as soon as possible “
Infectious disease doctor
Another common concern among the population is whether to choose between AstraZeneca or Moderna as a second dose. In this sense, the answer, already indicated in the official announcement, is no. If the combination is accepted, the second dose to be offered will be AstraZeneca or Moderna based on availability in each jurisdiction.
Regarding whether people waiting for the second dose have to call somewhere to receive it, the Ministry of Health explained that they will be contacted by the local health authority.
“The different jurisdictions are calling, in general, first to those who are at risk population (elderly and then with comorbidities) in order according to the time that has elapsed since the first dose of Sputnik V was given to offer them the option” , they specified.
As for the time that those who do not agree to combine will have to wait to complete their scheme with Sputnik, the health authorities could not offer a precise answer, since this will depend on their availability.
Regarding whether there is a history of heterologous vaccination schemes for other diseases, another frequent question, the infectologist Elena Obieta clarified that this strategy is quite common. In fact, “Sputnik V itself is a heterologous scheme because it has two different components,” he recalled.