Investigation of hepatitis.
D000293:Adolescent; D002648:Child; D006509:Hepatitis B / Q000453:epidemiology*; D006514:Hepatitis B Surface Antigens; D006525:Hepatitis, Viral, Human / Q000453:epidemiology*; D006801:Humans; D009520:New Zealand
D006514:Hepatitis B Surface Antigens