Quote: southyorksdave " they need to find out if the virus leaves behind antibodies '"
Antibody response is low and suspected to be short lived, but you are correct, serology tests are vital. The first antibody tests were as bad as 30% sensitive, which is completely useless. Roche will launch a serological diagnostic test this month and Abbott have launched a serology test (these the two big boys in diagnostic testing). The Abbott test I'm not convinced about, the Roche test will probably be good.