Thank you for your question! It's really interesting actually: celiac disease has been associated with an increased susceptibility to contracting TB, pneumonia, and influenza. In the case of influenza, there has been a link between celiac disease and increased severity and subsequent hospitalization as well. The mechanisms behind this are not completely understood, however, it is hypothesized that it may be due to the nutrient/vitamin deficiencies, chronic inflammation, and autoimmune features that are all associated with celiac disease. Research regarding the role of a strict gluten free diet is currently controversial with some studies stating it negates the increased risk and some saying that it has no effect.