As someone who had COVID-19, I've researched this issue a lot.<p>The single case presented here did have worse symptoms from the reinfection, but we do not know the antibody status after the first infection.<p>Other possible cases, involving nurses and such, also had much worse outcomes after the reinfection, but I think there is a selection bias in these cases.<p>There is the case of a Hong Kong man who only knew about his proven reinfection because he got tested in an airport, otherwise he was asymptomatic.<p>There was one case of a patient remaining infected for a very long time, but his infection immediately cleared after convalescent plasma was administered, so antibodies seem to work as expected.