RSV, the flu, and the winter cough: a parent's playbook

Every fall and winter, our exam rooms fill up with coughing, snotty, miserable little patients. Parents almost always ask the same question first: “Is this just a cold, or something worse?”

The honest answer is that most respiratory infections in kids look similar in the first 24–48 hours. Here’s how to tell them apart, what helps, and what doesn’t.

The usual suspects

• Common cold (rhinovirus, adenovirus, parainfluenza, etc.) — Runny nose, mild cough, mild fever, generally feels okay. Lasts 7–10 days.
• RSV (respiratory syncytial virus) — Starts like a cold; in babies and toddlers, can move into the lungs as bronchiolitis with wheezing, fast breathing, poor feeding. Peaks days 3–5.
• Flu (influenza) — Sudden onset, high fever, body aches, headache, dry cough. Kids often look more wiped out than with a cold.
• COVID-19 — Variable. Can mimic any of the above; sometimes loss of smell, headache, or GI symptoms.
• Croup (parainfluenza) — Barky “seal” cough, hoarse voice, often worse at night.

What actually helps at home

For colds, RSV, and the flu in kids who are still drinking and breathing comfortably:

• Saline nose drops + a bulb syringe for babies. Boring but the single most useful tool you own.
• Cool-mist humidifier in the room at night.
• Fluids, fluids, fluids. Small sips, frequently.
• Honey for cough — but only for children 1 year and older (never under 1). 1/2 to 1 teaspoon as needed.
• Acetaminophen / ibuprofen for fever and discomfort (ibuprofen only 6 months+). Treat the comfort, not the number.
• Rest. Boring advice, real medicine.

What doesn’t help — and may hurt

• Over-the-counter cough and cold medicines are not recommended under age 6, and most pediatricians extend that further. They don’t work well in kids and have real risks.
• Antibiotics do nothing for viruses. RSV, flu, COVID, and the common cold are all viral.
• Steam tents and hot showers — okay for croup, but won’t shorten any of these illnesses.

For RSV specifically (the babies, especially)

RSV is the one we worry about most in babies. The fever can be modest while the lungs are working hard. Watch the breathing, not the thermometer.

Call us — or 911 — if you see:

• Sucking in between the ribs or at the base of the neck with each breath
• Nostrils flaring with each breath
• Breathing faster than usual at rest (over 60/min in a young baby, over 40/min in a toddler)
• Pauses in breathing (apnea) in a young infant
• Bluish or grey color around the lips or fingertips
• Refusing to feed or fewer than half the usual wet diapers
• Wheezing that you can hear without a stethoscope
• A baby who is unusually sleepy, floppy, or hard to rouse

For the flu

We will sometimes prescribe oseltamivir (Tamiflu) if your child is in a high-risk group or seen within 48 hours of symptom onset. Annual flu shots from age 6 months are the single best protection — please don’t skip them.

Call us — same day — for any of these

• Any of the RSV breathing signs above
• Fever in a baby under 3 months (always)
• Fever over 104°F at any age, or fever lasting more than 3 days
• A cough lasting more than 2 weeks, or one that’s clearly getting worse after day 5
• Trouble keeping fluids down
• Wheezing in a child with no known asthma history
• Anything that worries you

A note from us

Most winter coughs run their course at home — and a pediatrician’s job is partly to tell you when to relax and partly to catch the one in twenty that needs more. Either way, that’s exactly what we’re here for.

This article is for general educational purposes and is not a substitute for advice from your child’s pediatrician.