European foulbrood, test (EVB).

European foulbrood, abbreviated EVB, is a bacterial disease that is contagious. It is possible to test a hive for this disease. You do this when symptoms seem to point toward EVB. Want to read more about EVB? Then read the Beekeeperpedia article

Notice: If the test kit is past its expiration date, this does not mean that it is no longer usable. As long as upon testing the control line becomes visible the test functions and the result is reliable.