After almost three years of trying to wholly eliminate the virus that causes Covid-19 from within its borders, the Chinese government has abruptly changed course. Now, the country is attempting to “live with Covid-19”. Testing is no longer required, and numbers of officially reported Covid-19 cases are at odds with scientific estimates of the situation.
While official estimates suggest there are 4,000 cases of Covid a day, scientists estimate the number is more like 1 million. Official death tolls are similarly unreliable. The lack of transparency from the Chinese government, and the lack of trust in what it’s saying about its domestic outbreak, has prompted concern across the world.
The US, Italy, Japan, Taiwan and India are among the countries that have already introduced strict checks on flights coming from China. The UK also now has a requirement for travellers from China to England to provide a pre-departure negative test. In addition, the UK Health Security Agency will soon start monitoring a sample of passengers to keep track of any new variants arriving.
These new policies in the west follow a period of largely “getting back to normal”. They’ve triggered a debate about whether testing travellers arriving in a country is a useful strategy, or simply performative. These arguments are confusing and circular, but the core issues are: what kind of testing is useful, and what objective does it serve?
The first point of testing is to identify positive cases to stop further transmission. Providing evidence of a negative test before boarding a flight will mean there are fewer positive cases on flights and therefore fewer arriving into a country. But imported cases make a substantial difference only if domestic cases are low. In summer 2020, when case numbers were low across Britain, it made sense to enforce strict policies to prevent importing Covid-19. New cases would get “seeded” within communities and trigger outbreaks.
Today, however, Covid-19 is endemic across Britain and the US. This doesn’t mean it is harmless, but it does mean that case numbers are unlikely to be affected by new imported cases. Testing passengers on flights coming to Britain in order to reduce domestic case numbers doesn’t make sense given this situation.
The second purpose of testing is to detect new variants that could be more transmissible, evade existing immunity by reinfecting people quickly, or cause more severe illness. While it’s impossible to completely stop the spread of a new variant, quickly detecting a new strain can help delay its spread and provide valuable data on how best to respond to a changing situation. Testing every single person on arrival isn’t necessary for this purpose; random sampling of passengers from China would be sufficient to keep a check on new variants and spot whether a new variant has emerged that has not yet spread widely in Britain.
Surveillance can also be done through wastewater testing on international aircraft. Wastewater that is flushed down plane toilets would indicate what variants passengers may have had, and doesn’t require individual-level data. Plane wastewater has already been used to show that – even when negative tests are presented pre-departure – there are positive Covid-19 cases among the passengers. The US is considering adding this testing to existing requirements of a negative test pre-departure.
It’s been three years since the World Health Organization first alerted the world to a new cluster of cases in Wuhan, and most countries are finding a way to live with Covid-19 through a combination of vaccines and major waves of infection. And while the disease is still a top 10 cause of death in Britain, and long Covid a continuing cause of disability, most countries seem to have accepted this toll as long as their hospitals don’t collapse. The UK is already seeing the NHS crumble, but this is not because of Covid-19. Twelve years of underinvestment in the NHS and its staff have strained the health system, which is now struggling to provide acute and chronic care.
Could a variant emerge that would change the entire picture? It seems unlikely, but we need to constantly assess the situation based on new data, and respond with suitable policies. We can’t live in a constant state of panic and worry, but we can prepare, plan and lay the groundwork for a rapid response to future health risks.
As we head into 2023, the centre of the pandemic has returned to China. Covid-19 has been a global hurricane, causing damage as it has torn across the world. Different places have been hit hard at different times, where governments have provided different levels of protection.
At the moment, China is getting hit badly. With a government intent on protecting its reputation and spinning official political narratives rather than providing transparency, it’s been hard to get a sense of what is happening there. Here again we have to remember that China is not just its government: its people are now facing their worst wave of Covid-19 yet, and its scientists are providing the world with valuable data, often at a great cost to themselves.
Prof Devi Sridhar is chair of global public health at the University of Edinburgh
