Testing 5,000 people in representative locations would be enough, according to the virologist. This would require the approval of the ethics committee and an order from the federal government beforehand. Von Laer was also convinced that the meaningful antibody value will also find its way into the Green Pass.
“Studies on this are currently underway and it will be possible to set a clear limit value, as is the case with hepatitis B, for example, from which one is considered protected,” she explained. In previous studies it could be determined that “from the antibody level of 100 BAU / ml (Binding Antibody Units) standardized by the World Health Organization (WHO), there is at least a high probability of protection,” Von Laer quoted the current state of research.
Those who have been vaccinated may be less protected than those who have recovered
With the vaccinated, however, it is often difficult to make statements about the value of the antibody titer. “As we can see, there are vaccination breakthroughs with the Delta variant, although the titer is high,” said Von Laer in an interview with the “TT”. Those who have gone through an infection develop anti-N antibodies (against the nucleocapsid antigen) and S antibodies (against the spike protein) as well as T cells (long-term immune response). The vaccinated, on the other hand, would only produce anti-S antibodies, explained the scientist. So you can find out who has already gone through corona disease.
The protection of those who have recovered is to be equated with the protection of those who have been vaccinated, whereas the immune protection of those who have recovered is even more stable. In those who have recovered, antibodies can still be detected after 18 months, and after the Pfizer vaccination, the titer value drops by around six percent per month.
As for the booster vaccination, Von Laer recommended a third prick after eight months for elderly and risk patients; she did not consider an antibody test to be necessary in those cases. Everyone else could wait with an antibody level above 100 BAU / ml to 150 BAU / ml, according to the Innsbruck doctor.
Finally, she renewed her call to citizens to get vaccinated: “If 15 to 20 percent in Austria are now vaccinated, we can declare the pandemic to be over, as in Denmark,” emphasized Von Laer. Then the pandemic could “be over in two or three months”.
