With every new variant of the coronavirus, the anxious question arises: Does the vaccination protection hold up? So far the answer has always been: yes. However, the vaccines on the market offer varying degrees of protection against the various mutants. However, it takes more time to be able to estimate with whom which vaccine works how well against which variant.
Researchers all over the world are investigating these questions and providing some very different and always provisional answers. The news came from Scotland in mid-June that the vaccine from Biontech / Pfizer prevented 80 percent of the infections with the Delta variant, while the vaccine from Astra Zeneca prevented only 60 percent of the infections. However, the protection against severe disease progression was much higher for both preparations, however, the case numbers are too small to recognize differences between the vaccines, the researchers write. However, the team emphasizes that such data “must be interpreted with caution”.
The good news is: vaccinating twice reliably protects against becoming seriously ill
In mid-June, Public Health England calculated an average of 80 percent protection against severe disease with the Delta variant after two vaccinations, without going into possible differences between the vaccines. The protection against a necessary treatment in the hospital because of Delta was put by the authority at 94 percent.
The Robert Koch Institute, in turn, gives the protection of mRNA vaccines such as that from Biontech / Pfizer against symptomatic infections with Delta at 88 percent. The protective effect of the vaccine from Astra Zeneca, however, is 60 percent. According to the RKI, the two types of vaccine provide far better protection against severe disease that requires hospital treatment. The protective effect for Biontech / Pfizer is 96 percent, that of the Astra Zeneca preparation at 92 percent – each after a complete vaccination with two doses, as the RKI emphasizes. Simple vaccination is far less effective.
On Monday, media reports finally revealed numbers from Israel that fit well with the current state of knowledge. Accordingly, the vaccine from Biontech / Pfizer prevents 93 percent of the serious disease courses but only 64 percent of the infections with the Delta variant. In March, when the Delta variant was by no means the dominant virus in Israel, protection against infection by this vaccine was estimated there at 91 percent, protection against serious illness was slightly higher at 98 percent.
If these figures are also confirmed in other countries, that would be mixed news. On the one hand, very few people become seriously ill if they become infected despite being vaccinated. On the other hand, more people who are vaccinated are infected with this virus variant than with other mutants. That makes efforts to slow the pandemic difficult.
It is still unclear how much the virus is actually spread by vaccinated people. However, data from India already indicate that people who have been vaccinated twice can produce dangerous quantities of the virus. A study among medical workers vaccinated with the Astra Zeneca vaccine came across infection clusters around individuals whose vaccination protection had failed.