- 乙型肝炎 yǐxínggānyán hepatitis Ban infectious inflammatory illness of the liver caused by the hepatitis B virus
- 乙型脑炎 yǐxíngnǎoyán Japanese encephalitisJapanese encephalitis; also known as epidemic encephalitis B
- 流行性乙型脑炎 liúxíngxìngyǐxíngnǎoyán Japanese encephalitisJapanese B encephalitis, a viral infection of the brain transmitted by mosquitoes