Abstract
The use of coronavirus disease 2019 RNA vaccines in pregnant women led to reports on the first cases of newborns with antibodies to sudden acute respiratory syndrome coronavirus 2 (SARS-CoV-2), a phenomenon that was unknown when using immunizations with inactivated viruses. Thus, this study aimed to report a case of passive anti-SARS-CoV-2 immunity in a newborn through immunoprophylaxis of a pregnant woman who received the CoronaVac® vaccine in the third trimester of pregnancy. Twenty-four hours after delivery, samples were collected from the newborn and screened by enzyme immunoassays, which revealed antibodies to SARS-CoV-2.