Q: My 2-month-old has a fever after vaccinations. The hospital said it's rhinovirus. What should I do?

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Question:

My 2-month-old (65 days old) has a fever. We went to the ER, and all the tests (urine, blood, X-ray) came back clean. However, my baby tested positive for rhinovirus. Can this virus cause a fever? They sent us home because all the lab results were in the normal range, but the fever has returned, staying between 37.5°C and 37.8°C. Should I give a fever reducer and just monitor? My baby also had their 2-month vaccinations yesterday afternoon, and the fever started about 22 hours later. Could this just be a reaction to the shots?

Answer:

It must be very worrying that your 65-day-old baby has a fever.

[Summary of the Current Situation]

• ER tests (urine, blood, X-ray) were all normal.

• Positive for rhinovirus → This is a common cold virus and can certainly cause a fever.

• Current temperature is 37.5-37.8°C → This is in the low-grade fever range.

• Fever started about 22 hours after vaccination → It could be a vaccine reaction, but a co-occurring rhinovirus infection is also possible.

[What to Do at Home Now]

• Dress your baby in light clothing and keep the room at a comfortable temperature.

• Offer breast milk/formula in small, frequent amounts → Monitor feeding volume and the number of wet diapers.

• Use fever reducers only if your baby seems uncomfortable:

- Acetaminophen (e.g., Tylenol) at 10-15 mg/kg per dose, every 4-6 hours.

- Check the concentration (mg/mL) on the bottle label to calculate the correct dose → Use the provided measuring device for accuracy.

• Do not use wet towels or give a lukewarm bath to bring the fever down.

[When to Return to the ER/Pediatrician]

• Breathing fast or showing retractions (skin pulling in under the ribcage).

• Appears limp or won't make eye contact.

• No urine for more than 8 hours.

• Fever persists above 38.5°C or lasts for more than 48 hours.

• Refusing to feed or is unusually fussy and irritable.

[Vaccination Fever vs. Viral Fever]

A low-grade fever within 24-48 hours post-vaccination is common. However, since your baby tested positive for rhinovirus, you should also watch for cold symptoms like a runny nose or cough. It's possible for both to be happening at the same time.

To summarize the key points: Since the tests were normal and the fever is low-grade, it's reasonable to monitor your baby at home while ensuring good hydration and feeding. If you notice any of the warning signs listed above, seek medical re-evaluation immediately.

For extra peace of mind and clear guidance when tracking your child's symptoms, the FeverCoach app is always there to help.

https://fevercoach.us