Fig. 2.

Extreme aged centenarians and non-centenarians infected with SARS-CoV-2 elicit a robust anti-spike IgG response. Peripheral blood samples were collected from 16 residents of a long-term care facility in Halifax, Nova Scotia, who were considered exposed to the SARS-CoV-2 virus. All exposed residents were tested for the presence of virus in the upper respiratory tract by nasopharyngeal swabbing following by PCR to detect the viral N gene. Blood was collected approximately 30 days after a positive PCR test. Serum separated was subjected to a direct ELISA assay to determine the magnitude of SARS-CoV-2 spike protein directed antibodies of the IgG isotype. The ELISA was analyzed by participant group: centenarians PCR positive for SARS-CoV-2 nucleic acid encoding gene N (Ai); centenarians PCR negative for SARS-CoV-2 nucleic acid encoding gene N (Aii); non-centenarians PCR positive for SARS-CoV-2 nucleic acid encoding gene N (Bi); non-centenarians PCR negative for SARS-CoV-2 nucleic acid encoding gene N (Bii). Endpoint titers for each group are summarized (C).