"According to the , the choice to abandon systematic testing and contract tracing, which were effective in Korea and Taiwan, was a major mistake that contributed to the spread of the virus in virtually every country. The ultimate cause of this alarming delay were strategic choices. Italy was quickly forced to adopt a strategy of absolute confinement in order to halt the epidemic, as China had previously done. Other countries waited far too long to react, largely on the basis of the and crypto-Darwinian strategy of "herd immunity." Boris Johnson's United Kingdom was entirely passive in its initial approach, and other countries equivocated and delayed their restrictive measures, such as France and Germany, not to mention the United States. By adopting a strategy of "mitigation," or epidemic delay by "," these countries have de facto renounced any serious attempt to keep the virus under control from the start through the use of systematic screening and general confinement of the population, as was done in and Hubei province. According to the forecasts of the German and French governments, the strategy of collective immunity necessitates 50 to 80 percent contamination across the entire population. This amounts to accepting the deaths of hundreds of thousands — even millions — of people who are supposedly the "most fragile." All the while, the WHO's recommendations were very clear: states must not abandon systematic screening and contact tracing of anyone who tests positive for the virus."