A vaccination strategy called “prime and pull” shows that subcutaneous administration of HSV-tk (an attenuated strain of HSV, described as the “prime”) and subsequent topical administration of the chemokines CXCL9 and CXCL10, described as “pull,” to recruit HSV-specific T cells at the site of infection protects against genital HSV-2 infection (49). Here, TKT is linked to infection.