Brucellae are intracellular parasites, penetrating and reproducing in phagocytic and non-phagocytic cells; thus, in most cases, they remain inaccessible to the immune system and damage virtually all bodily organs and systems. Brucellae have relatively low virulence, toxicity, and pyrogenicity, which leads to weak induction of inflammatory cytokines (TNF, INF). They reproduce in the endoplasmic reticulum and induce cell necrosis.