Thursday, October 20, 2016

The Human Microbiome, Koch's Postulates, Infection Prevention

This week our own Dr. Wenzel presented an update on the dynamic human microbiome, exploring the interaction of bacterial diversity, homeostasis and infection prevention. Masterful.  He will be giving this lecture at the 2016 ID Week conference in New Orleans, next week.

For hospital infection prevention, much of the current thought is on both preserving the current microbiome and restoration of bacterial normalcy in select situations (fecal microbiota transplants), as summarized in this scholarly review.

Our knowledge of the human microbiome is rapidly expanding, as witnessed by the number of publication cited over the last several years in PubMed (over 5,500 articless last year alone vs. 245 in 2005).

Our understanding of bacteria, disease and wellness is evolving such that Koch's Postulates are not so neatly applicable anymore. Some bacteria are important components of the normal microbiota, preserving homeostasis, yet pathogenic at other times (Staphylococcal species on the nose and skin, fermicutes, bacteriodetes and Clostiridium in the gut).

As we bathe patients with chlorhexidine and decolonize with mupirocin, decreasing the burden of potentially dangerous pathogens to prevent hospital acquired infection, we alter the normal microbiome, possibly disrupting our protective microbial balance. 

We are in a constant evolution with the microbes and we have much to learn.