Carbohydrates are ubiquitous in nature and present across all kingdoms of life – bacteria, fungi, viruses, yeast, plants, animals and humans. They are essential to many biological processes. However, due to their complexity and heterogeneous nature they are often neglected, sometimes referred to as the ‘dark matter’ of biology. Nevertheless, due to their extensive biological impact on health and disease, glycans and the field of glycobiology have become increasingly popular in recent years, giving rise to glycan-based drug development and therapeutics. Forecasting of communicable diseases predicts that we will see an increase in pandemics of humans and livestock due to global loss of biodiversity from changes to land use, intensification of agriculture, climate change and disruption of ecosystems. As such, the development of point-of-care devices to detect pathogens is vital to prevent the transmission of infectious disease, as we have seen with the COVID-19 pandemic. So, can glycans be exploited to detect COVID-19 and other infectious diseases? And is this technology sensitive and accurate? Here, I discuss the structure and function of glycans, the current glycan-based therapeutics and how glycan binding can be exploited for detection of infectious disease, like COVID-19.