My research aims at understanding how the mucosa-associated immune system recovers from acute infections and the long-term consequences for host immunity and metabolism. Acute infections at barrier sites, such as gut and lungs, are frequent occurrences worldwide, specially in populations under poor nutrition and sanitization conditions. We have demonstrated that defined episodes of intestinal infection can disrupt the immune communication in the gut and lead to the development of an immunological scar. This process drives profound long-term consequences, including metabolic changes, delayed cognitive and growth development and to the failure to respond properly to food and pathogens. Individuals exposed to such infections are particularly unable to respond against oral vaccines and are also more prone to develop inflammatory bowel diseases. Therefore, understanding the mechanisms mediating these long-term effects of infection to the host are essential to prevent the failure of oral vaccines, such as the polio vaccine, and also for the design of more efficient strategies to control the devastating effects of infection/malnutrition, particularly in low- to middle- income countries.