2006, Max Planck Institute for Infection Biology
Shigella flexneri is the causative agent of Shigellosis, a severe form of bloody diarrhea which is prevalent in countries with poor sanitary conditions. Bacterial dysentery represents a severe health policy problem: Worldwide, an estimated 165 million cases of shigellosis annually occur resulting in at least 1.1 million deaths mainly among children. Shigella, which is transmitted through the fecal-oral route, is a remarkably virulent pathogen. In clinical trials, ten to a hundred bacteria are enough to trigger disease. S. flexneri is responsible for most of the infections, while infections with S. dysenteriae, the only species that produces Shigatoxin, are less common but can lead to devastating epidemics. The inflammatory response elicited by Shigella is rich in neutrophils, which are, like macrophages, effective antibacterial cells. Interestingly, neutrophils can also attack and kill Shigella extracellularly by producing net-like structures (Neutrophil Extracellular Traps, NETs).