The three vaccines approved so far by the European Medicines Agency (EMA) require two doses to achieve high protection against COVID-19. Those of Pfizer/BioNTech should be administered with 21 days of difference, those of Modern with 28 days and those of AstraZeneca/Oxford in an interval of between 8 and 12 weeks.
However, these two injections might not be enough, according to Bill Gates warned last Tuesday in an interview for the program ‘Evening News’ of CBS.
The Microsoft founder and philanthropist assured that a third dose may be needed to prevent severe cases of the new variants of the coronavirus that have been detected in South Africa and the United Kingdom: “The discussion now is whether we only need to obtain one super high current vaccine coverage, or do we need a third dose that is the same, or do we need a modified vaccine”.
In fact, the businessman assured that the five US companies that have vaccines “are considering making this modification and adding it” so that people who vaccinated with the two doses of the drug can receive a third injection if they need it: “I think it is reasonably likely that let’s have a Adjusted vaccine just to make absolutely sure that when these variants arrive in the U.S. do not escape the protection of the vaccine”.
Study in South Africa
The South African variant is the one that most worries experts because of the high possibility that it will escape the antibodies. Therefore, Gates is funding studies in South Africa whose mission is toterminate if AstraZeneca, Johnson & Johnson, and Novavax vaccines are equally effective against the most contagious variant. The data obtained so far does not appear to be very negative.
In this sense, the businessman specified that “AstraZeneca, in particular, has a challenge with the variant ”. The vaccine developed by this company decreases its protection against this variant detected in South Africa, but can prevent the most serious cases.
On the other hand, the vaccines of Johnson & Johnson and Novavax “are a little less effective, but still effective enough that we should remove viruses with them as quickly as possible while we study this idea of adjusting the vaccine”.
The Pfizer Vaccine
The South African variant could also significantly reduce the protection of the Pfizer / BionNTech vaccine. S
pecifically, a study published in the New England Journal of Medicine (NEJM) revealed that effectiveness could decrease by two thirds, though it is not clear whether this reduction can render the vaccine ineffective, since scientists discovered that the vaccine was able to neutralize the virus.
Pei-Yong Shi, professor at UTMB and co-author of the study, trust that the vaccine will be effective enough against the variant or, at least, help protect against serious illness and death. Health experts have said it’s the single most important factor in preventing stretched health systems from becoming overwhelmed.