Jennifer Heimall, MD, attending physician and Elizabeth Paige Lavin Endowed Chair in Research and Clinical Care in Immunology at Children’s Hospital of Philadelphia, discusses whether people with primary immunodeficiencies can receive the COVID-19 vaccine. The COVID-19 vaccine introduces a small amount of genetic material that is presented on body cells to the T cells, which talk to B cells and create antibodies. Clinical trials have shown that the T-cell response is beneficial against COVID-19 infection even if a patient’s B cells are not functioning. Dr Heimall notes that patients with primary immunodeficiencies or those on immunosuppressants should benefit from receiving the COVID-19 vaccine.