Viral Upper Respiratory Tract Infection (URTI): This is the most common cause of cough, colds, and fever, especially during seasonal peaks. The symptoms are typical for a self-limiting viral infection.

Influenza: Especially during flu season, influenza can present with similar symptoms and should be considered, particularly if the onset is sudden and the fever is high.
Acute Bronchitis: Often follows a viral upper respiratory infection, acute bronchitis can cause a persistent cough and may be accompanied by fever.
Pneumonia: Can present with cough, fever, and sometimes symptoms of a cold. It's more likely if the symptoms are severe or if the patient has underlying health conditions.

Pertussis (Whooping Cough): Although less common due to vaccination, pertussis can cause severe coughing fits and is a critical diagnosis not to miss, especially in infants or those not vaccinated.
Tuberculosis (TB): A chronic infection that can cause cough, fever, and other systemic symptoms. It's crucial to consider TB, especially in high-risk populations or those with exposure history.
Pneumocystis jirovecii Pneumonia (PCP): In immunocompromised patients, PCP can present with non-specific symptoms including cough and fever, making it a critical diagnosis not to miss.

Sarcoidosis: A systemic disease that can cause cough and fever among other symptoms, though it's less common and typically presents with additional findings like lymphadenopathy or skin lesions.
Lymphoma: Certain types of lymphoma can cause systemic symptoms including fever and cough, though this would be a rare initial presentation.
Histoplasmosis or Coccidioidomycosis: Fungal infections that can cause respiratory symptoms, including cough and fever, more commonly seen in specific geographic areas or in immunocompromised individuals.