Population-wide prophylactic vaccination is the principal means of quelling the COVID-19 pandemic. For this to succeed, knowledge of vaccine efficacy is imperative. Patients with lymphoid malignancies have an increased mortality risk from COVID-19. Many patients are apparently cured but have long-term immune defects. Our lack of knowledge of COVID-19 vaccination responses confers a morbidity and mortality risk in this population and significant societal impact. This study will assess COVID-19 vaccine efficacy defined by immunological responses (anti-spike IgG, virus neutralisation, T-cell recall).