nowing how to control the spread of coronavirus is not rocket science. But actually doing it has proved elusive and difficult for many governments across the world. When China first alerted the World Health Organization about a novel coronavirus on 31 December, the countdown began for countries to each prepare. Some, such as South Korea, Taiwan and Hong Kong, were scarred by their recent experiences with two other deadly coronaviruses, Mers and Sars, and so reacted quickly to the coming threat. Others, such as the UK and US, consumed with domestic political issues, watched and waited, anticipating that this new virus would be more similar to a bad flu strain. We are now almost four months into this pandemic, and the lessons that can be drawn from east Asian countries on how best to control this coronavirus and keep daily new cases as low as possible are clear. Eight aspects in particular stand out as important for governments to recognise as they navigate difficult choices ahead. They also provide a guide for what the public should be expecting of and demanding from their governments. The first is to aggressively identify where the virus is and break chains of transmission. This requires a “test, trace, isolate” policy that involves mass community testing, tracing those who had been in contact in the previous week with any individual testing positive, and putting all of those individuals into a mandatory quarantine. Governments and local municipalities would have to recruit and train foot soldiers to carry this out. While testing itself is not a solution, it is a crucial part of a package of public health interventions needed to keep identifying clusters of infection and breaking these apart. Keeping daily cases low through this approach keeps the burden off hospitals and allows bare-bones economic and social activity to occur. The second is to protect health and social care workers who are most at risk from contracting the virus and who are exposed to high viral loads during the course of doing their jobs. This protection needs to involve not only priority access to testing, but also appropriate personal protective gear that is readily available. Much attention has been paid to ensuring that there are enough ventilators, beds and oxygen and much less to the need for sufficient and skilled frontline staff, who cannot be manufactured in days or weeks. The third is to keep constant surveillance of the virus using tracking systems to detect whether certain parts of the country are becoming hotspots and whether sub-populations, such as migrants living in close quarters, have a higher incidence of the virus. This can be done by building on existing flu surveillance networks and ensuring that data is shared in real time. Tied into this point is lesson four, which is about monitoring borders for imported cases. Travel bans towards certain countries have limited effectiveness, but blanket 14-day quarantines for any international arrivals can ensure that new cases are detected quickly rather than setting off more clusters of infections. The fifth is that clear and honest communication with the public is required to keep trust and compliance with the necessary policy guidance. This is an unsettling time for everyone as rules are introduced around daily behaviour and misinformation is rife. Therefore, consistent and straightforward messaging on why policies are being introduced and transparency on how governments are making their decisions is essential to create a beacon of trusted information in a sea of noise. The sixth is recognising that any “exit” strategy is not like a switch that means life will go back to pre-Covid days. A “new normal” will need to be adjusted to, which is likely to involve distancing whenever possible; possible temperature checks when entering public buildings and offices; and the use of face masks in public. The goal is to achieve some economic and social activity while keeping procedures in place that reduce the transmission of the virus. The seventh lesson is that lockdowns, if introduced early and quickly, can slow the spread of the virus, but are not a solution by themselves. They are a costly and crude policy instrument that should be used as sparingly as possible. They allow governments to buy time and use this time to massively increase important public health infrastructure. The final lesson is that all of the above are short-term strategies while countries await key scientific findings to create informed policy decisions and find the ultimate “exit strategy”. There are huge gaps in what we know about this virus, including about immunity, the individual risk of developing severe symptoms and how long it will take to develop an effective vaccine or therapy. But the steps above can ensure that countries keep daily new cases low and avoid a repeat of the 1918 flu pandemic, which was determined, in the end, by the “survival of the fittest”. • Devi Sridhar is chair of global public health at the University of Edinburgh