Iron is an essential nutrient for cell survival and is crucial for DNA replication, mitochondrial function and erythropoiesis. However, the immunological role of
iron in
viral infections has not been well defined. Here we found the
iron salt ferric ammonium citrate (FAC) inhibited Influenza A virus, HIV virus, Zika virus, and Enterovirus 71 (EV71)
infections. Of note, both
iron ion and
citrate ion were required for the
antiviral capability of FAC, as other
iron salts and
citrates did not exhibit viral inhibition. Mechanistically, FAC inhibited
viral infection through inducing viral fusion and blocking endosomal viral release. These were further evidenced by the fact that FAC induced
liposome aggregation and intracellular vesicle fusion, which was associated with a unique
iron-dependent cell death. Our results demonstrate a novel
antiviral function of FAC and suggest a therapeutic potential for
iron in the control of
viral infections.