COVID-19 is a novel strain of Coronavirus, a type of respiratory virus, which was not previously identified in humans. Although seasonal flu is also a contagious respiratory virus, that may affect some people worse than others, we have had the opportunity to study seasonal flu for many years which means we are more aware of how it spreads and changes each year. There are also effective vaccines that have been developed for flu to protect those more at risk of becoming very unwell. Our understanding of the novel coronavirus is much more limited and there are currently no vaccinations to prevent the disease and we are still trying to understand this new disease fully.