Common Cold
Usually gradual onset with runny/stuffy nose, mild cough, and low or no fever.
Symptoms typically peak within a few days and resolve within 7–10 days.
Flu (Influenza)
Often sudden onset with higher fever, body aches, fatigue, and more pronounced illness than a typical cold.
Young infants may show poor feeding and irritability rather than clear "aches."
RSV (Respiratory Syncytial Virus)
Common in infants and young children; can cause wheezing, rapid breathing, and, in some cases, more serious lower-airway illness like bronchiolitis.
Infants under 6 months and premature babies are at higher risk of more severe RSV.
When to Seek Care
Rapid or labored breathing, flaring nostrils, visible rib retractions, bluish lips, poor feeding, or lethargy need prompt evaluation regardless of which virus is suspected.
FAQ
Can these be told apart without testing?
There’s overlap in symptoms; a clinician may use testing to confirm, especially for flu or RSV in higher-risk infants.
Is RSV always serious?
Most cases are mild and cold-like, but close monitoring in young infants is important.
Do these viruses need antibiotics?
No — they are viral; antibiotics don’t treat them unless a bacterial complication develops.
How can I reduce the risk of catching these?
Frequent handwashing, avoiding sick contacts, and following recommended vaccination schedules where applicable can help.