Review Article

Vaccination for Patients With Inflammatory Bowel Disease During the COVID-19 Pandemic

Jayne Doherty; Sean Fennessy; Roisin Stack; Neil O' Morain; Garret Cullen; Elizabeth J. Ryan; Cillian De Gascun; Glen A. Doherty


Aliment Pharmacol Ther. 2021;54(9):1110-1123. 

In This Article

Abstract and Introduction


Background: Poor immune responses are frequently observed in patients with inflammatory bowel disease (IBD) receiving established vaccines; risk factors include immunosuppressants and active disease.

Aims: To summarise available information regarding immune responses achieved in patients with IBD receiving established vaccines. Using this information, to identify risk factors in the IBD population related to poor vaccine-induced immunity that may be applicable to vaccines against COVID-19.

Methods: We undertook a literature review on immunity to currently recommended vaccines for patients with IBD and to COVID-19 vaccines and summarised the relevant literature.

Results: Patients with IBD have reduced immune responses following vaccination compared to the general population. Factors including the use of immunomodulators and anti-TNF agents reduce response rates. Patients with IBD should be vaccinated against COVID-19 at the earliest opportunity as recommended by International Advisory Committees, and vaccination should not be deferred because a patient is receiving immune-modifying therapies. Antibody titres to COVID-19 vaccines appear to be reduced in patients receiving anti-TNF therapy, especially in combination with immunomodulators after one vaccination. Therefore, we should optimise any established risk factors that could impact response to vaccination in patients with IBD before vaccination.

Conclusions: Ideally, patients with IBD should be vaccinated at the earliest opportunity against COVID-19. Patients should be in remission and, if possible, have their corticosteroid dose minimised before vaccination. Further research is required to determine the impact of different biologics on vaccine response to COVID-19 and the potential for booster vaccines or heterologous prime-boost vaccinations in the IBD population.


A novel coronavirus referred to as SARS-CoV-2 (severe acute respiratory syndrome coronavirus 21) was identified in late 2019 as the causative agent of a respiratory syndrome named coronavirus disease (COVID-19) and has subsequently resulted in a worldwide pandemic. As of summer 2021, COVID-19 has been confirmed in 184 324 026 people worldwide and has resulted in 3 992 680 deaths.[1] It is clear that risk factors such as older age, obesity and underlying conditions such as heart disease, diabetes and immune suppression can increase mortality. The Centres for Disease Control and Preventions (CDC) definition of immunocompromised individuals includes patients on prolonged courses of corticosteroids or other immunosuppressive medications, a group which includes a high proportion of patients with IBD.[2]

The aim of the SECURE-IBD database established during this current pandemic is to determine the risk of patients with IBD developing severe outcomes from COVID-19. To date, 6328 cases of COVID-19 have been reported in patients with IBD with 103 deaths.[3] From cases reported to SECURE-IBD 15% of patients with IBD have been hospitalised and 3% have required ICU admission.[3] A recent meta-analysis found that reassuringly the risk of contracting severe COVID-19 in patients with IBD is not higher than the general population and the use of biologics may be associated with better outcomes for patients who contract COVID-19.[4] Managing the risks of COVID-19 in patients with IBD has been the subject of much effort. Given the development of numerous vaccines against COVID-19, attention has turned to the role of vaccination as a key tool to manage the risks associated with COVID-19.

Effective vaccines generate an immune response that mimics that induced by natural infection. Vaccinated individuals can produce large quantities of high-affinity antibodies or effector T cells quickly, thus protecting them from severe disease if subsequently exposed to the pathogen. Vaccine-induced protective immune responses are especially important in vulnerable cohorts especially those considered immunocompromised which include a sub-cohort of patients with IBD. There is evidence that patients with IBD remain at significant risk of vaccine-preventable infections, suggesting vaccines confer suboptimal protection in this cohort.[5,6]

Several vaccines against COVID-19 have recently been approved for use and are being deployed in widespread immunisation programmes. In this review article, we aim to address several key questions which will help inform our approach to COVID-19 vaccination in patients with IBD. Firstly, we will discuss whether patients with IBD show altered vaccine responses and which disease characteristics contribute to modulating vaccine-induced immunity. Secondly, we will review what can be learnt from the existing data on the impact of IBD therapies on response to vaccination by focusing on a number of established anti-viral vaccines. Finally, we will examine how this informs our approach to the delivery of the current and upcoming COVID-19 vaccines to maximise their impact in the IBD community.