The Impact of Obesity and Metabolic Syndrome on Vaccination Success.

The increase in the prevalence of obesity represents a worldwide phenomenon which is associated with several chronic diseases. In this review, we summarize published data showing how obesity, alone or together with the metabolic syndrome, induces defects in B cells similar to those induced by aging, contributes to systemic and B cell intrinsic inflammation and increases the secretion of autoimmune antibodies. We show that obese individuals contract more bacterial, viral, and fungal infections as compared to lean controls. These include periodontal, cutaneous, gastric, and respiratory tract infections, as well as postsurgical infections occurring after solid organ transplantation and surgeries for weight loss. Moreover, because obese individuals have a compromised immune system, they respond poorly to vaccination against influenza, hepatitis B, tetanus, and rabies. The results in this review highlight the importance to vaccinate individuals with obesity and/or with metabolic syndrome to prevent morbidity from vaccine-preventable diseases.