Disease X. It's a term evocative of scary movies about runaway pandemics. In fact, it is a term coined by the World Health Organisation (WHO) and is part of a broader plan designed to avert precisely that. Its operating principles of vigilance, scientific scrutiny and proactive preparations are at play as the authorities in Singapore and elsewhere respond to the outbreak of a mysterious pneumonia-like illness in Wuhan, China. That there are systems in place and that these have kicked in without undue fuss is good news and assuring in these uncertain times. In the WHO lexicon, Disease X refers to unknown pathogens that may lead to an epidemic. The descriptor originated in 2018 as experts acknowledged the need to prioritise research and development for means to address such threats. Research on vaccines for "known unknowns" takes time but there are battle plans designed to contain outbreaks even as efforts are under way to identify the causal agents.

Since the world was alerted to the Wuhan cluster of patients, Singapore has rolled out several measures: The Health Ministry has sent out circulars to doctors to look out for suspected cases. It has issued advice to travellers to Wuhan on how to stay safe and what to do when unwell. Travellers from Wuhan will have to undergo temperature screening at Changi Airport, with suspected cases being referred to hospitals for further assessment. These multi-pronged measures serve to halt the spread of disease while not causing unnecessary alarm and inconvenience.