Growth rates of bacteria in vivo.

A quantitative framework is proposed for analyzing bacterial dynamics at the site of a biofilm infection. A key parameter in this analysis is the bacterial specific growth rate. The literature was surveyed for quantitative measurements of bacterial specific growth rate in vivo in animals or humans, with and without an implant present, and in different stages of infection. These few measurements offer clues, but the chemical microenvironment, physiology, and rates of microbial growth prevailing in vivo remain poorly characterized. New techniques for measuring bacterial growth rates, and for accessing in vivo chemistry and physiology, are becoming available and offer the potential to greatly improve our understanding of bacterial growth and metabolism in vivo. This article issues a call for the application of such techniques in situ and in vivo.