PF4 and Thrombocytopenia: Definitive diagnosis was based on the following as human medicine: (1) clinical signs appearing 4–42 days post‐vaccination; (2) thrombocytopenia; (3) presence of thrombus in lung vessels, alveolar septa vessels, gastric vessels and small intestine, as well as other organs, as confirmed by histopathologic examination; (4) positive result from anti‐heparin/PF4 ELISA testing.