The virus now causes primary infection called varicella or chickenpox, and it has two stages - primary viremia and secondary viremia.

这时候引起的初叫水痘，有第一病毒血症与第二病毒血症2个阶段。

I think the leg must be getting septic.

我觉得他的腿引发了脓毒血症。

In primary viremia the virus infects a part of immune system in the liver and spleen, called the reticuloendothelial system, which is made of phagocytic cells.

第一病毒血症中，病毒入侵肝脾的部分免疫系统，即由巨噬细胞组成的网状内皮系统。

About two weeks after entering the body, the virus starts infecting immune cells themselves - specifically T cells - and that is considered the secondary viremia.

周之后，病毒开始侵犯免疫细胞，特别是T细胞，这就是第二病毒血症。

Birds act as a reservoir for the virus, meaning the virus can replicate at high enough levels to cause significant viremia, or elevated viral blood counts, which allows for transmission to other uninfected mosquitoes.

鸟类是此病毒的宿主，意味着病毒可在其体内以较高的水平复制，以至于导致病毒血症，继而传播给其它未受的蚊子。