It is an open question to what extent protection against reinfection persists after overcoming a SARS-CoV-2 infection. The “Rhineland Study”, a population-based study conducted by DZNE in the Bonn area, is now providing new findings in this regard. Blood samples taken last year indicate that an important component of immunity—the levels of specific neutralizing antibodies against the coronavirus—had dropped in most of the study participants with a previous infection after four to five months. In some, antibody titers even fell below the detection limit. These results, published in the scientific journal Nature Communications, lay the groundwork for planned follow-up studies.