Varicella zoster virus in inflammatory bowel disease patients: what every gastroenterologist should know

Primary Varicella Zoster virus (VZV) infection results in varicella (chickenpox) while its reactivation results in herpes zoster (HZ; shingles). Patients with Inflammatory Bowel Disease (IBD) are susceptible to complications of primary VZV infection and have an increased risk of HZ. Concerns of VZV and HZ infection in the IBD population has been highlighted by the emergence of JAK-inhibitors and their safety profile in this patient population such as tofacitinib for the treatment of ulcerative colitis (UC). The current pipeline of emerging therapies include novel molecules targeting multiple pathways including JAK/signal transducer and cytokine signalling pathways such as JAK/STAT. Hence VZV and HZ will be increasingly relevant for gastroenterologists treating IBD patients in light of these emerging therapies.