Even if someone experiences mild symptoms after a vaccination or tests positive for the coronavirus, the vaccine is still effectively doing what it’s supposed to do: prevent severe disease progression and death.
All of the vaccines approved by the health authorities of the European Union (EMA) and the United States (FDA) have shown high efficacy. For example, mRNA vaccines from BioNtech-Pfizer and Moderna achieve about 95% efficacy, while AstraZeneca’s vector vaccine achieves 76%, according to recent data. However, this means that it’s still possible to become infected after a vaccination. Still, if efficacy is considered according to the severity of the course of the disease, all vaccines perform significantly better than going without. In the event of infection, for instance, vaccines usually prevent the type of severe reaction that requires people to be put on ventilators” or even kills them.
In Germany, however, there have been some cases in which seniors in nursing homes still had severe COVID-19 courses even after vaccination. Some even died. The reason? The body needs about two weeks to fully build up immunity. Thus, complete protection is only achieved two weeks after a patient has received his or her second vaccination shot.
But only with time will we learn how long the immunity from the COVID vaccines lasts. That’s why the period after vaccines are licensed is also known as Phase IV of vaccine development. We are now in the middle of this phase. Reliable statements about the duration of immunity will only be possible after several months or even years. - DW