Jamie is a 1-year-old girl who is coughing and has had rhinorrhea with yellowish discharge for the past day. Her father says today he felt like she had a fever and has not been eating or pla

Scenario: Jamie is a 1-year-old girl who is coughing and has had rhinorrhea with yellowish discharge for the past day. Her father says today he felt like she had a fever and has not been eating or playing; she has been mostly sleeping. Her 5-year-old sibling has had a cold for a week.
Pertinent Information Provided:
Medications: none.
Allergies: no known drug allergies.
Vaccinations: up to date for age.
Social history: in day care; lives with mother, father, and 5-year-old sibling.
Physical examination: vital signs – temperature 101.5?F; pulse 120 beats per minute; respirations 34 per minute; blood pressure 100/60 mmHg; pulse oximeter 92%.
General: sitting in father’s lap; ill, lethargic appearance, and coughing.
HEENT: nasal flaring, nasal mucus yellowish bilaterally; oropharynx with mild erythema.
Neck: small anterior and posterior cervical nodes.
CV: unremarkable.
Lungs: intercostal retractions, expiratory wheezing.
Abdomen: unremarkable.
Answer the following questions or provide responses based on this scenario.
Question: What is the most likely diagnosis and pathogen causing this disorder? Discuss the mode of transmission and discuss data that supports your decision: and what diagnostic test, if any, should be done?
Final Question: based on answers to previous questions: What treatment plan would you develop for this patient?
Disclaimer: It should be noted that this scenario with question(s) has been submitted multiple times to provide credit to expert(s) for answering more that one question related to scenario.