Many countries are stepping up requirements for incoming travelers to show a recent negative COVID-19 test. The U.S. will accept results from either a standard test for COVID-19 or a rapid test. The test must have been taken no more than three days before flying to the U.S. England has a similar setup, accepting results from both types of tests. However, health authorities there also require that the tests meet certain standards for accuracy. European Union officials recently agreed to standardize testing requirements for entry across the 27-nation bloc.