He was coming down with mononucleosis, but we could not know that then.

其实他当时已经染上了单核细胞增多症，但我们并不知道那件事。

Epstein-Barr is best known for causing " mono, " or infectious mononucleosis, in teenagers and young adults.

EB病毒最广为人知的是会在青少年中引起" 单核细胞增多症" 或传染性单核细胞增多症。

In fact, one common infection that's been proposed is the Epstein-Barr virus — more commonly known as mononucleosis, or mono.

事实上，研究人员提出的一种常见感染是爱泼斯坦-巴尔病毒，更常称为单核细胞增多症，或单核细胞增多症。