Herpes simplex virus type 2 (HSV-2) causes life-long infection with episodic reactivation. For decades, antiviral drugs, such as guanosine analogues (aciclovir and its prodrug valaciclovir), have been used to treat or prevent frequent and painful episodes. One outstanding question about HSV is why transmission is not stopped by these suppressive treatments. In The Lancet, Christine Johnston and...
