PROBABLY BECAUSE THEY DON’T NEED THEM: Asymptomatic Cases of Coronavirus Seem to Lose Antibodies Sooner, Study Finds. I think we’ll find that T-cell immunity is what usually does the job, and people with asymptomatic cases clear the infection faster and hence don’t develop a strong antibody response. But given that T-cells have a long “memory,” that doesn’t mean less immunity.