Q: My child keeps getting recurrent high fevers up to 40.3°C every week for three weeks. Should we get a blood test?

Medically reviewed by Sang Hyun Ahn, MD

Content edited by Myeongchan Kim, MD

This post is a dramatization of a question and answer session experienced by our actual medical reviewers. Please note that this content is for informational purposes only and does not constitute medical advice. Always consult with a qualified healthcare professional for any health concerns or before making any decisions related to your health or treatment.

Question:

Hello, my child has been experiencing recurrent high fevers every week.

Three weeks ago on a Sunday morning, a fever of 38.5–39.5°C started. There was no runny nose or cough, and the fever would drop with medication only to rise again. By Monday morning, it finally went down. The pediatrician mentioned it might have been a mild case of stomatitis and gave us medication.

Then, the weekend before last, a fever of 38.6°C started on Saturday evening. It dropped a bit with medication but spiked to 40.3°C by Sunday morning. It kept fluctuating between 38°C and 40°C. There were no other symptoms, and although the fever made my child tired, they still ate and played well. We visited the pediatrician on Monday, who said the throat looked slightly swollen and prescribed antibiotics. The high fever continued until Tuesday afternoon before dropping.

Yesterday evening, the fever started yet again. It was 38.1°C, which went down after taking medication (still no runny nose, cough, or diarrhea). But at 5 AM, my baby rolled over to me and felt burning hot—I checked, and it was 40.3°C again.

This is the third high fever in just a month, and I am terrified because it keeps hitting 40°C every time. Is my baby just fighting off new germs? Should we ask for a blood test, or is this part of normal growing pains? Please help!

Answer:

I completely understand how incredibly worried you must be. Dealing with recurrent high fevers for three weeks, especially when it spikes to 40.3°C in the early morning, is a very frightening experience for any parent.

Based on the pattern you described:

• High fevers (38.5–40.3°C) are repeating at weekly intervals.

• The fever lasts for 2–3 days and then improves.

• The fever occurs without any other accompanying respiratory or gastrointestinal symptoms.

• Despite the high fever, your child is still eating and playing well.

This specific pattern of recurrent fever can lead us to suspect a few possibilities:

1. Sequential viral infections: Your child might be getting exposed to different viruses back-to-back (very common if they attend daycare or play with other children).

2. PFAPA Syndrome: This stands for Periodic Fever, Aphthous stomatitis, Pharyngitis, and Adenitis, which is a syndrome characterized by recurrent episodes of high fever.

3. Incompletely treated bacterial infection: An underlying infection that wasn't fully cleared during previous treatments.

Immediate Recommendations:

Please visit your pediatrician today and request a blood test. When you go, be sure to bring a written log of the fever pattern over the last three weeks (including dates, highest temperatures, and duration of the fevers). You can directly ask the doctor, "Given the recurrent high fevers, is it necessary to do a blood test now?"

When to visit the Emergency Room:

Please seek immediate emergency care if you notice any of the following:

• The fever is accompanied by severe lethargy or a complete refusal to eat/drink.

• Rashes or joint swelling appear.

• The fever does not drop below 38°C even after taking fever reducers.

• Your child experiences convulsions, seizures, or a decrease in consciousness.

Please be reassured that a fever of 40°C by itself does not cause brain damage. However, the repetitive pattern absolutely requires an investigation to pinpoint the underlying cause. A blood test will allow the doctor to check inflammation markers and white blood cell counts, which will help guide the proper treatment.

The fact that your child is eating and playing well is a very positive clinical sign. However, three weeks of cyclical high fevers is not just standard growing pains—it warrants an in-person medical evaluation and testing. Please consult your pediatrician as soon as possible for a thorough assessment.

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

fevercoach.us

Apple App Store

Google Play

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