The prominent importance of IFN signalling in driving the host response to varicella zoster virus is also demonstrated by the increasing rates of reactivation observed when its pathway is intentionally inhibited by a monoclonal antibody antagonist of the type 1 interferon receptor (IFNAR), anifrolumab, employed in the management of Systemic lupus erythematosus (SLE) [31]. This evidence concerns the gene IFNAR1 and systemic lupus erythematosus.