Since the first COVID-19 vaccines became available late last year, supply shortages and limited access resulted in some governments adopting controversial strategies, such as delaying second doses beyond the recommended manufacturing guidelines, as well as mixing the first and second dose of different COVID New, preliminary data from emerging clinical studies, as well as rising concerns over the very rare risk of blood clot linked to the Oxford-AstraZeneca vaccine, suggest that these strategies may be working. The pre-print results from a clinical trial in Spain suggest that taking two different doses of the COVID-19 vaccine may result in better protection. The trial involved 663 people and was led by the Carlos III Health Institute in Madrid.
The first dose of the COVID-19 vaccine was given to all participants, and it uses an adenoviruses to deliver the vaccine to the body. n an interview with CTV News, the professor of immunology at the University of Toronto said that they only have the media reports, not the actual data. For several hundred people who had the AstraZeneca vaccine as a first dose, and then were given the Pfizer vaccine as a second dose, they got a very good boost in immune response.
It can only be partially explained why this happens. One hypothesis is that the two vaccines might cause different parts of the immune system to respond in different ways, resulting in a stronger, long-term response. Watts said that it was a good idea to switch because the immune system doesn't recognize the nanoparticles.
It doesn't surprise me that they got a very good response. It is important to note that the study still needs to undergo a formal peer review, but encouragingly, the data from the UK study published in The Lancet earlier this month suggests that receiving your second dose of the vaccine from a different brand than the first one. This boost was not completely unexpected, as it is actually roots in decades of science.
In a study published by researchers at the Nation Institute for Food and Drug Control in China, immune system boost was observed in mice who had first received adenoviruses vectored vaccines followed by a second dose with an mRNA vaccine. When the vaccine order was reversed, the same improvement in the T cell response was not observed. The Spanish study has some limitations, such as a lack of comparative data between individuals who had received both doses of the vaccine as well as those who had received two doses of the vaccine, the study's control group had simply not.
The team was careful to note that the study doesn't provide evidence that mixing vaccines is a better option than administering them as they were designed, and that the results don't say that mixing vaccines is a better option than administering them. For now, answering questions with regards to safety in an evolving situation is a priority, but larger studies are required to make these conclusions."
