Recognizing and Managing Common Infant Illnesses: A Myth vs. Medicine Perspective
Dear parents, let’s face this reality. Your baby will likely get sick. While it hurts and makes parents anxious, it is a way for the baby to build their immune system. The difficult part is knowing when a sniffle is just a cold—and when it's something more.
As a pediatrician, I deal with worried parents every day and as a parent myself, I’ve felt that worry too, in fact countless times.
My first child started daycare at six months of age. Within weeks of going to daycare, she was bringing home every bug. Today is runny nose, tomorrow cough and next is a fever. It felt nonstop. Even though I knew what to expect, I still checked her temperature constantly. I’ve seen firsthand how fast a fever can climb in a baby—and how high fevers can be complicated with febrile seizures.
That’s why recognizing signs of infections early and knowing when to call your pediatrician—or go straight to the ER—matters a lot!
Common Illnesses in Infants
Let’s briefly go over the most common illnesses I see in babies under one year—and what to watch for in these illnesses.
1. Colds (or Upper Respiratory Infections)
Symptoms:
Runny or stuffy nose
Sneezing
Mild cough
Low-grade fever
What to do:
Use saline drops and a bulb syringe to clear the nose
Offer extra fluids
Use a humidifier in the room (avoid menthol in humidifier)
Most colds in infants and children are mild and often go away in 7–10 days. But call your pediatrician if:
Your baby is under 3 months old and has a fever
Breathing faster than normal
Not taking enough feeds or refusing to eat
2. Fever
When a baby has a fever, it means their body is fighting something off. For infants, a temperature of 100.4°F (38°C) or higher is a concern and warrants attention.
What I do: I keep a reliable thermometer at home and use it any time my baby feels warm. I never guess based on touch as some parents do, not to judge anyone.
Call your pediatrician right away if:
Your baby is younger than 3 months and has a temperature of 100.4°F (38°C) or higher
The fever lasts more than 24 hours
Your baby is very sleepy or irritable or not just acting like themselves
Act fast and don’t wait unnecessarily. In infants, a simple fever can sometimes be the first sign of something more serious—like a urinary tract infection, pneumonia, or even meningitis.
🔬 Myth vs. Medicine Spotlight: What Research Says
🧠 Myth: Every infant fever means serious illness and needs antibiotics
Parents often panic at the first sign of fever in their baby. It's easy to assume it’s a sign of something severe, especially in infants under three months. But not all fevers indicate a dangerous infection, and not all require antibiotics.
📚 Key Study #1
A 2004 study published in JAMA analyzed how emergency departments managed febrile infants under 90 days old. The study found that although over 30% of infants were hospitalized and more than 50% received antibiotics, the actual rate of serious bacterial infection was very low—only 1.8% had bacteremia and 0.5% had meningitis.
This tells us that while caution is appropriate, unnecessary interventions can be avoided with good clinical judgment and thorough evaluation. Antibiotics aren’t always the answer—what matters most is monitoring symptoms and acting based on the full clinical picture.
Reference: Managing Febrile Infants: Clinical Guidelines Are No Better Than Clinical Judgment But More Expensive. AAP Grand Rounds July 2004; 12 (1): 1–2. https://doi.org/10.1542/gr.12-1-1
📖 Key Study #2
The American Academy of Pediatrics published updated guidelines in Pediatrics in 2021, recommending careful observation and selective testing for infants aged 8 to 60 days who appear well. These guidelines help pediatricians make evidence-informed decisions about when to observe, test, or treat young infants with fever.
The emphasis is on individualized care—recognizing that fever alone, especially when a child looks well and is feeding, doesn’t always call for invasive testing or hospital admission.
Reference: Robert H. et al, Evaluation and Management of Well-Appearing Febrile Infants 8 to 60 Days Old. Pediatrics August 2021; 148 (2): e2021052228. 10.1542/peds.2021-052228
🩺 Pediatrician Insight
As a pediatrician, I respect fever as a signal—not a diagnosis. I teach parents that fever is the body’s response to infection, not a danger in itself. My job is to evaluate what’s behind the fever. And as a parent, I know how stressful it feels when the thermometer creeps up. But when you have reliable information and a plan, it becomes easier to act with clarity and calm.
3. Ear Infections
Symptoms:
Fussiness during feeds
Tugging at the ear
Fever
Trouble sleeping
Babies can't tell you their ear hurts but you will probably notice some changes in their mood, eating, or sleep. If you notice any of these, it’s worth having their ears checked.
4. Stomach Bugs (Gastroenteritis)
Symptoms:
Vomiting
Diarrhea
Less wet diapers
Poor appetite
Stomach bugs are many times caused by viral infection. They generally do not require prescription medications. But the biggest risk here is dehydration. If your baby is not making tears when crying or having fewer than 4 wet diapers a day, call your doctor immediately.
5. Bronchiolitis (Often Caused by RSV)
This affects babies’ small airways and can make them have difficulty with breathing.
Watch for:
Fast or labored breathing
Flaring nostrils
Wheezing
Trouble feeding
In some cases, hospitalization is needed, and supplemental oxygen can be provided to them. I’ve seen babies go from mild cough to struggling to breathe in hours.
Pay Attention to Energy Level
One of the most important signs that something’s not right in a baby is a sudden drop in energy. If your baby seems weak, is unusually quiet, or less responsive—do not wait. Those are symptoms of a serious medical condition.
I once got a call from a mom whose baby “just seemed off”—not moving much, not feeding well but you know what? No fever. No cough. She was just different.
That baby was diagnosed with a serious infection. Her call—and quick action—made all the difference.
When to Go to the ER
While it is okay to follow your instinct, here are non-negotiables:
Trouble breathing
Skin looks blue or very pale
Baby won’t wake or is very hard to wake
Fever in a baby under 3 months
Seizures
Not eating and not peeing enough
My Approach at Home
Even as a pediatrician, I don’t take chances or feel overconfident. I watch my kids closely when they’re sick. I take temperatures often. I keep track of wet diapers. I examine them looking at their skin for any rashes—and I always encourage parents to do the same.
While babies can’t tell us what’s wrong with them, they show us, if we know how to look.
Final Thoughts
You don’t have to figure it out alone. If something feels off, reach out. That’s what we’re here for.
If you ever need help recognizing signs or deciding what to do, we’re ready to support you. No question is too small—because with babies, small signs can mean big things.
