noun
hepatitis B
Medical term for the liver infection caused by the hepatitis B virus.
B型肝炎の予防接種を受ける。
I get vaccinated against hepatitis B.
General term for hepatitis; B型肝炎 specifies the type caused by the hepatitis B virus.
Compound of B (the virus type) + 型 (type) + 肝炎 (hepatitis).