Sigma Xi Publications



American Scientist

The Rise of New Pathogens

The plague and cholera have killed millions of people over the past centuries. Each of these diseases is caused by a bacterium that began as a harmless ancestor microorganism but evolved to become one of humanity’s worst scourges. This process, known as pathogen emergence, is difficult to predict. In “How Bacterial Pathogens Emerge,” Salvador Almagro-Moreno describes how his laboratory and others are trying to understand the biological rules and evolutionary forces that make a microorganism transition to causing disease in humans. For example, human-made ecological perturbations, such as climate change and pollution of ecosystems, are drastically affecting the spread and proliferation of disease-causing bacteria, accelerating the acquisition of antibiotic resistance, and increasing the likelihood that novel pathogens will emerge. Research in this area is beginning to provide the tools needed to forecast the events and drivers that lead to the emergence of novel infectious agents. Such research is pivotal for successful disease management and control. (Illustration by Joana C. Carvalho).

May–June 2022

Sigma Xi Publications