The lockdown is wreaking havoc with the economy, children are missing vital education, those with mental health problems or experiencing domestic abuse are suffering, and people in need of non-Covid-19 healthcare are not getting it. Though the cabinet seems divided over the answer, the question is genuine: when will the UK exit the Covid-19 lockdown?

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If the government has an exit strategy, it is keeping it closely guarded. As with so much about the government’s response, such as the identity of most members of its Covid-19 advisory group, information is released on a strictly need-to-know basis. What we do know is that the government will not set a specific date. It is right not to do so. Donald Trump may believe he is battling a germ that is “brilliant”, a characteristic not normally associated with a microscopic clump of genetic material, but even he abandoned his initial goal of opening up the US by Easter. This “very smart” virus does not observe religious festivals or read his tweets.

The seeming unwillingness of the British government to share its thinking with the public contrasts starkly with the approach taken elsewhere. The European Union has published a roadmap that lays out a phased approach for containing the virus. Cynics might be forgiven for recalling the contrast between the EU’s detailed Brexit impact assessments and the superficial British ones, which had to be prised from the hands of ministers many months later. In the case of coronavirus, the UK would do well to follow the European roadmap, which recommends developing a robust system of contact tracing, expanding testing capacity and reinforcing PPE supplies as among the first steps towards lifting a lockdown.

Other European countries have also set out their proposals in varying levels of detail. Angela Merkel gave an in-depth explanation of the scientific basis behind Germany’s lockdown strategy, drawing on a deep understanding of the epidemiology. In a speech marked by humility and acceptance that mistakes had been made, Emmanuel Macron explained that the process would be lengthy: schools would be opened when the data supported it, but restaurants and bars would remain closed for much longer.

The countries that are most advanced in this process are those that closed down earliest, and thus managed to better contain the spread of the virus. This approach contrasts with that of the United Kingdom, which delayed its lockdown. Germany, which has attracted widespread praise for its ability to deliver widespread testing, is opening up smaller shops, as is Austria, although this is subject to customers distancing from each other and wearing face coverings. The Czech Republic, which like its neighbour Slovakia has strongly encouraged face coverings, is also opening small businesses. Denmark, meanwhile, is starting to open up elementary schools. These governments have made clear that continued progress is dependent on the course of the pandemic, and restrictions might well be reimposed – but they have been much more open with citizens about their respective approaches than the UK has been.

The key elements that a British exit strategy must include are fairly obvious, providing, as the UK government keeps repeating, that these decisions are led by science. The science is clear. The only way to get back to anything like normality is to get what epidemiologists call the reproduction number, or R 0 , below 1. Put another way, we must find ways to ensure that those who are infected in a community pass that infection on to fewer than one other person. We can be certain this point is being made by England’s chief medical officer, an experienced infectious disease epidemiologist. But how can this be achieved?

The EU’s document provides helpful guidance for what the UK’s strategy might look like. First, it should not even consider lifting restrictions until it has adequate data to be sure that the R 0 really is below one. It can only do so if it has sufficient testing in place, for both the virus, determining who is infected, and the antibody, telling us who has been infected in the past and is therefore, hopefully, immune. This will require many more tests than the government’s current daily target of 100,000.

At the same time, it will be important to show that the death rate really is falling, which will require far better data than is currently being provided, which has created considerable confusion about the number of deaths outside hospitals, especially in care homes. And the NHS must be ready for any resurgence once restrictions are lifted. This means having enough PPE, which is no more than an aspiration at present. Finally, the UK will need sufficient public health capacity to tackle resurgent infections, a task that will require enormous efforts to reverse the effects of a decade of cuts.

Easing the lockdown will have to be accompanied by other measures to reduce transmission, such as continued physical distancing and, increasingly likely, face coverings, as in France, Austria, the Czech Republic and Slovakia. Change must be gradual, with health authorities closely monitoring the effects. In Italy, regions are taking the first very hesitant steps at different speeds, while in Spain those in construction and manufacturing sectors who are now permitted to go back to work must maintain stringent precautions.

Throughout this process, it will be essential to follow what other countries are doing. The approaches taken by various European countries offer a natural laboratory in which to test our own ideas. We must avoid simplistic comparisons, but also accept that the different approaches offer many learning opportunities. Unfortunately, some government advisers seem reluctant to take this opportunity.

• Martin McKee is professor of European public health at the London School of Hygiene and Tropical Medicine and an adviser to the World Health Organization