The 2019-coronavirus disease (COVID-19), caused by SARS-CoV-2, was identified as the source of pneumonia cases in Wuhan city in China. It rapidly spread worldwide and was declared by WHO as a pandemic. COVID-19 vaccines are expected to be the breakthrough in controlling the pandemic. However, studies performed only in healthy adults, and specifically excluded patients who were under immunomodulatory/biologic therapy, thus excluding patients with chronic inflammatory diseases (IBD). In this study we wish to understand vaccine efficacy and immunological response in IBD patients.

Overall Aims:

1. To assess the immune response to COVID-19 vaccination in patients with IBD.
2. Comparing the short and long term immune response to vaccination among subgroups receiving different therapies.
3. To evaluate the different variables affecting immunity of these patients.
4. To assess adverse reactions to COVID-19 vaccines and IBD related complications.

Specifically:

1. To assess serologic response to COVID-19 vaccine(s) in patients with IBD treated with anti-TNF agents (+/- immunomodulators) compared to

   1. Healthy controls
   2. Patients with IBD not treated with anti-TNF (+/- immunomodulators)

2. To characterize serologic response: seroconversion, seroprotection and persistence of COVID-19 vaccine(s) in patients with IBD

3. To identify factors associated with serologic response

4. Side effects to vaccines

5. IBD exacerbation compared to activity at baseline

6. Symptomatic COVID-19

Inclusion Criteria:

• 1. Adults >18 years of age 2. Patients with either Crohn's disease, ulcerative colitis, ileostomy, pouch 3. Not vaccinated to COVID-19 [i.e. before 2 mRNA Pfizer vaccines provided, or before any vaccine provided as one injection 4. Ability to attend follow up visits 5. Ability to understand and sign an informed consent form

Exclusion Criteria:

• 1. Pregnant women](streamdown:incomplete-link)

IBD patients and healthy volunteers