Emerging research highlights the intricate roles of microbiota and immune modulation in health and disease. A new broad-spectrum antiviral mRNA platform inspired by a rare immune deficiency shows potential against viral infections by modulating interferon-stimulated gene pathways. Studies connect specific bacterial strains with cancer risk, such as colibactin-producing E. coli linked to colorectal cancer in familial adenomatous polyposis. Additionally, novel findings implicate bacterial infections and inflammatory pathways in neurodegenerative conditions such as Alzheimer’s. These discoveries refine our understanding of host-pathogen interactions and open pathways for innovative therapeutic strategies.