Omicron vaccines: These are the adapted corona vaccines!
The vaccines against BA.1 come from the manufacturers BioNTech/Pfizer and Moderna . In addition, special vaccines against BA.4/BA.5 from both companies were approved by the EU Commission in September and October. What is known about the effectiveness and does a booster with the new vaccines make sense?
How effective is the adapted vaccination against omicron?
BioNTech/Pfizer ‘s BA.1 vaccine is a so-called bivalent vaccine. This is a combination of a vaccine adapted to BA.1 and the previous COVID-19 vaccine .
The effectiveness was tested in a study with 1,200 participants aged at least 56 years. The number of neutralizing antibodies against BA.1 in the blood serum of the study participants was measured before and four weeks after the booster vaccination. The result: the antibody level had increased significantly after the vaccination compared to the previous measurement – on average by a factor of 9.1 to 10.9. The vaccine is considered to be well tolerated.
The study data from Moderna also show an increased level of antibodies against subvariant BA.1 after subjects had received a bivalent vaccine. The effectiveness was examined in 1,800 participants over the age of 55 and in 600 people between the ages of 18 and 55.
The vaccines that were approved shortly thereafter are also bivalent vaccines that contain a mixture of mRNA from the wild type and the omicron subtypes BA.4 and BA.5 . As with the previous adapted BA.1 vaccine, all other components of the vaccine remain the same. BioNTech/Pfizer and Moderna state that for the new vaccines, based on preclinical data, a high immune response can be demonstrated against all previously known omicron subvariants as well as against the wild type of the coronavirus .
Protective effect of the BA.1 vaccine also against BA.4 and BA.5?
According to the manufacturer’s information, the vaccines adapted to BA.1 also have a certain protective effect against subtypes BA.4 and BA.5, but this is naturally less than against BA.1.
The blood sera of the study participants were also examined as part of the BioNTech/Pfizer study with regard to the formation of antibodies against the omicron subtypes BA.4 and BA.5. It was found that after the vaccination, neutralizing antibodies against the two subtypes were also formed. However, three times fewer antibodies were formed than against BA.1.
Vaccination with one of the vaccines adapted to BA.1 thus increases protection against BA.4 and BA.5, despite being less effective than one of the previously available vaccines. This is because there are significantly fewer mutations between subtypes BA.1 and BA.4 or BA.5 than between BA.5 and the wild type of the coronavirus.
Vaccine against BA.4 and BA.5 available since September
In addition to the vaccines adapted to BA.1, the vaccine from BioNTech/Pfizer adapted to BA.4 and BA.5 is currently available in Germany. In addition, on October 20, 2022, the European Commission approved a Moderna vaccine adapted to the subvariants. When this will be used in Germany is still open at the moment.
The Standing Vaccination Commission (STIKO) issued a recommendation on the adapted vaccines on September 20th. In principle, all persons aged twelve and over who have not yet received a booster vaccination (third vaccination) are recommended one with a vaccine adapted to Omikron.
The STIKO recommends a fourth vaccination with one of the new vaccines for staff in the nursing and medical sector, among others. The recommendation also applies to people with an increased risk of a severe course of COVID-19 , for example people over the age of 60 or with certain underlying diseases.
A fifth vaccination is already recommended for people who are particularly at risk, such as the very old or residents of nursing homes. A minimum interval of six months (four months in exceptional cases) should be observed between vaccinations.
