Scientific understanding of the immune response to COVID-19 is incomplete but numerous research studies are underway. There is little evidence to suggest that exposure to other coronaviruses can confer protection against SARS-CoV-2. There is very good evidence that it takes at least 14 days to develop an antibody response to SARS-CoV-2. A significant proportion of people exposed to SARS-CoV-2 make very little or no detectable antibodies at all. There is insufficient scientific evidence to know whether the presence of SARS-CoV-2 antibodies confers protection from subsequent infections, and if so at what level. The duration of immunity is not clear; long-term monitoring of this in large studies will be needed to provide clarity. Antibodies are only one part of the immune response to infection, which is complex, and understanding the overall immune response to COVID-19 is very important. Additional high-quality research evidence is needed in order to indicate the likelihood of future outbreaks of disease, how often and when they are likely to occur, and to inform the development of any future immunisation programmes.