Four main mechanisms by which HFVs induce thrombocytopenia.

aDestruction of platelets by direct interaction: HFV can bind platelets directly causing activation and granule release. bImmunological destruction of platelet-virus complexes: Thrombocytopenia can be mediated by macrophages sequestration of platelet-virus complexes at the infection site or/and in the spleen, platelets-virus-leukocyte aggregation and subsequent phagocytosis by macrophages or destruction mediated by platelet-virus associated antibodies. cMegakaryocytes or Megakaryocyte precursors impairment: HFV can infect megakaryocytes or their precursor causing reduction in platelets number or impairment in their function. dInhibition of platelet function: Some unidentified soluble factors present in plasma from infected patients can inhibit aggregation of platelets from healthy individuals.