Inhaled anthrax is particularly deadly. Although the spores are dormant when breathed in, they germinate when exposed to a warm, moist environment, such as the lungs. Not all particles are small enough to pass into the alveoli, or air sacs, but those that do begin to multiply and may spread to the lymphatic system. When the spores germinate in the lymph nodes, several toxins are released. Particles illustrated are not to scale.
Review Date 5/19/2023
Updated by: Jatin M. Vyas, MD, PhD, Associate Professor in Medicine, Harvard Medical School; Associate in Medicine, Division of Infectious Disease, Department of Medicine, Massachusetts General Hospital, Boston, MA. Also reviewed by David C. Dugdale, MD, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.