Chapter 2. Introduction to Microbes and Infection in the Modern World

Microbial infections single-handedly account for many diseases, acute as well as chronic, throughout the modern world, in developed as well as developing nations. In many cases, microbes are required for normal immune function, as germ-free animals have dysfunctional immunity. As a consequence, the traditional idea that all bacteria are bad, and thus the over-prescription of broad-spectrum antibiotics has led not only to multi-drug resistance, but also an imbalance of innocuous vs. harmful pathogens outside in warm bodies of water where we swim, as well as on and inside of our bodies (skin, mouth, lung, gut, urinary tract, vagina, etc.). This has created many difficulties, not only for patients, but also for healthcare providers, who not only have hospital-specific profiles for which drug-resistant bacterial strains (Gram-negative and/or positive) are prevalent in various patient-care facilities, but also worries about complicating and life-threatening incurable infections, obtained by traditional modes of transmission, or following invasive surgical procedures (e.g., implants, cancer resections, corrective surgery, etc.), and spread among patients, as well as the nurses and doctors who treat them. The Human Microbiome Project is a recent initiative to help derive essential understanding of how to discern which microbes are helpful vs. harmful, in an effort to determine improved preventative healthcare (probiotic maintenance, etc.), and in cases of diagnosed disease, the best course of treatment and how we may innovate more effective therapies.