Virus neutralization tests are an alternative method in the world trade. Complement fixation tests are a common serum antibody diagnose and survey method. PCR can diagnose the disease quickly.

Three tests (neutralization, sedimentation and dissociation) were used for determining the secretion intensity of ABH blood substance in saliva in 135 persons with known blood groups.

Serum tests including neutralization test, immune recall responses, and anti HAV IgG were performed 10 years after the initial immunization.