Immune Thrombocytopenic Purpura (ITP): This condition is characterized by low platelet count due to immune-mediated destruction of platelets. It often follows a viral infection, and the patient's recent recovery from a viral illness makes this a plausible diagnosis.

Viral-Associated Thrombocytopenia: Certain viral infections can directly affect the bone marrow, leading to thrombocytopenia. The recent viral illness could be the cause of the thrombocytopenia.
Drug-Induced Thrombocytopenia: If the patient was taking any medications during the viral illness, some drugs can induce thrombocytopenia as a side effect.

Thrombotic Thrombocytopenic Purpura (TTP): Although less common, TPP is a life-threatening condition that presents with thrombocytopenia, microangiopathic hemolytic anemia, renal failure, and neurological symptoms. It requires prompt diagnosis and treatment.
Heparin-Induced Thrombocytopenia (HIT): If the patient received heparin during the illness, HIT is a potentially fatal condition that must be considered, despite its lower likelihood.
Disseminated Intravascular Coagulation (DIC): This is a serious disorder in which the proteins responsible for blood clotting become overactive, leading to widespread clotting and bleeding. It can be triggered by severe infections and requires immediate attention.

Congenital Thrombocytopenias: These are a group of rare genetic disorders affecting platelet production or function. While unlikely given the acute presentation following a viral illness, they should be considered if other diagnoses are ruled out.
Bone Marrow Failure Syndromes: Conditions like aplastic anemia or myelodysplastic syndromes can cause thrombocytopenia but are rare and typically present with additional cytopenias (anemia, leukopenia).