Bacteria and Viruses
Platelet counts can be affected by diseases caused by viruses, such as parvovirus, Epstein-Barr virus or chickenpox. HIV-positive people often experience thrombocytopenia. Platelet counts can be affected by cytomegalovirus or mononucleosis. Bacterial infections that affect the blood can also cause platelet destruction or reduction. Blood poisoning can be caused by a widespread bacterial infection, and this can reduce the platelet count.
Genetic Condition
A low platelet count can also be caused by genetic disorders. Some of these disorders are May-haggling syndrome and Wiskott Aldrich Syndrome.