A follow-up study carried out by the University Clinic of Navarra on 709 of its professionals has shown that protection against Covid-19 increases with hybrid immunity, when natural immunity -generated by having passed the infection- is combined with that generated after infection. administration of the virus vaccine.
Between March and December 2021, blood tests were carried out to study the production of antibodies and cellular immunity in a group of professionals from the Clinic who had been inoculated with combinations of the M.oderna, Pfizer o AstraZeneca, and that made up five different vaccination guidelines. The results of the work have now been published in an article in the journal Scientific Reports.
Gabriel Reina, microbiologist at the University Clinic of Navarra and senior author of the study, highlights that «sover a very large population» and underlines «the robustness of the results thanks to the nine-month follow-up and the novelty of having introduced the study of cellular immunity at two points in the study».
“We have information on the levels of antibodies and we have been able to observe their dynamics according to the different vaccination guidelines and, also, we have differentiated them in people who had passed the SARS-CoV-2 virus infection from those who had not suffered it” Queen explains.
This specialist points out that “the second dose of the vaccine does not provide more protection in people who had been vaccinated once and who had passed the infection”, concluding that “hybrid immunity is the one that confers more powerful immunity and is maintained for Throughout the nine months of the study, both in antibody levels and in cellular immunity itself, which is the ability of our immune system to fight specifically and effectively against the virus, regardless of the variant.”
Hybrid immunity is the one that confers the most powerful immunity and is maintained throughout the nine months of the study
On the other hand, the study has made it possible to assess the effectiveness of vaccines developed with messenger RNA technology (Moderna, Pfizer) and compare it with that of a recombinant virus (AstraZeneca). “We wanted to know how long the protection offered by vaccines that had been developed with a very new technology and, therefore, we set out to measure immunity over nine months, and we have observed that mRNA vaccines induce a humoral response – of antibodies – and more powerful and durable cell phone».
José Luis del Pozo, director of the Microbiology and Infectious Diseases services, points out that «cWith this work we confirm that vaccines work. We have already seen that they reduce the transmissibility of the virus and mortalitybut with this work we justify that they are effective because they generate lasting cellular immunity, not only because they generate the production of antibodies».
Given the administration of new doses of vaccines, Del Pozo indicates that “the logical thing is that the recommendations regarding new doses of the vaccine be established based on the health risks of each person, in addition to whether they have generated cellular immunity. or not”.