In 2015, South Korea experienced an outbreak of Middle East respiratory syndrome, or MERS. Between May and July, 186 people contracted the MERS virus; 38 eventually died.
This diagram shows how quickly the pathogen spread within and between hospitals via a handful of “superspreaders.”
Case numbers are from the South Korean Ministry of Health, listed in the order that the individuals were diagnosed. Hover your mouse over the markers on the diagram to learn more about individual cases.