Q: My child has had a high fever for 4 days with a swollen throat, despite a negative flu test. Should we test for other viruses?
- Myeongchan Kim
- May 31
- 3 min read
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:
My child has had a high fever for 4 days. On Thursday morning, the fever hit 38.8°C. I gave a fever reducer and it went down, but the fever returned later with a runny nose. We saw a doctor who said the throat was a bit swollen and prescribed medication. However, the fever kept fluctuating and spiked to 39.6°C on Friday morning. We went back to the clinic, where a flu test came back negative. The doctor noted the throat was severely swollen and gave IV fluids. I thought my child was getting better, but the fever spiked again to 39.8°C early this morning. A fever reducer brings it down temporarily, but it spikes right back up during the day. Should we be testing for other viruses? My child has never had a fever last this long, and I want to know why this is happening.
Answer:
I understand how concerning it is when your child has a high fever that persists for four days. It is very stressful to see a fever constantly fluctuating.
When to Seek Immediate Care
If you notice any of the following warning signs, please take your child to an Urgent Care or Emergency Room today:
Breathing difficulties, such as wheezing or the chest sinking in below the ribs (retractions) while breathing.
Signs of dehydration, including no urine for more than 8 hours, or a dry mouth, lips, and tongue.
Extreme lethargy, where the child is constantly lying down and cannot make eye contact.
A stiff neck, severe headache, or repeated vomiting.
A red rash on the skin that does not fade or turn white when pressed.
What You Can Do at Home Right Now
Offer water or electrolyte drinks frequently in small amounts (every 15 to 30 minutes) to prevent dehydration.
Dress your child in a single, light layer of clothing and keep the room at a comfortable temperature (around 20-22°C or 68-72°F).
Administer fever reducers only when the child is uncomfortable. Avoid using wet towels or lukewarm baths to force the fever down.
Keep a daily log of your child's fluid intake, urine frequency and color, and overall activity level.
Typical Course of Viral Fevers
Viral infections accompanied by a swollen throat (pharyngitis) can commonly cause high fevers that last for 3 to 5 days. Even though the flu test was negative, there are many other viruses—such as Adenovirus, Enterovirus, or Epstein-Barr Virus (EBV)—that cause similar symptoms. Most of these viral infections will naturally improve over time with supportive care.
When to Consider Further Testing
You should contact your pediatrician to discuss if further testing (such as blood tests, urine tests, or a re-evaluation for strep throat) is needed if:
The fever lasts for 5 days or longer.
Any of the warning signs mentioned above appear.
Your child's symptoms worsen after 48 hours, especially if they are currently taking prescribed antibiotics.
Tips for Accessing Care
If it is the weekend or after-hours, check if your health insurance provides a 24-hour nurse advice line that you can utilize.
If you decide to visit an Urgent Care center, checking your insurance network beforehand can help minimize unexpected out-of-pocket costs.
For today, focus heavily on keeping your child hydrated and observing their symptoms closely. If the fever continues into tomorrow, or if any of the urgent warning signs develop at any point, please seek an in-person medical evaluation immediately.
For extra peace of mind and clear guidance when tracking your child's symptoms, the FeverCoach app is always there to help.
