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Does this describe your child's symptoms?

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Fifth Disease
Fifth Disease


Your child has a fever if:

  • Rectal, Ear or Temporal Artery (TA) temperature: 100.4° F (38.0° C) or higher
  • Oral or Pacifier temperature:  100° F (37.8° C) or higher
  • Under the arm (Axillary or armpit) temperature:  99° F (37.2° C) or higher
  • Limitation: Ear (Tympanic Membrane) temperatures are not reliable before 6 months of age
  • Temporal artery and skin infrared temperatures may be reliable in young infants (new research)
  • Use this guideline if fever is your child's only symptom


  • Main cause: colds and other viral infections
  • Fever may be the only symptom for the first 24 hours (i.e., viral fevers). The onset of symptoms (runny nose, cough, diarrhea, etc.) are often delayed. In the case of Roseola, fever may be the only symptom for 2 or 3 days.
  • The cause of the fever usually can't be determined until other symptoms develop. That may take 24 hours.
  • Bacterial infections (e.g.,  Strep throat or urinary tract infections) also cause fever
  • Teething does not cause fever

Fever and Crying

  • Fever on its own shouldn’t cause much crying
  • Frequent crying in a child with fever is caused by pain until proven otherwise
  • Possible hidden causes are ear infections, urinary tract infections, sore throats and meningitis.

Normal Variation of Temperature

  • Rectal: A reading of 98.6° F (37° C) is just the average rectal temperature. It normally can change from 96.8° F (36° C) in the morning to a high of 100.3° F (37.9° C) in the late afternoon.
  • Oral: A reading of 97.6° F (36.5° C) is just the average oral temperature. It normally can change from a low of 95.8° F (35.5° C) in the morning to a high of 99.9° F (37.7° C) in the late afternoon.

Return to School

  • Your child can return to child care or school after the fever is gone and your child feels well enough to participate in normal activities.

If not, see these topics

When to Call Your Doctor

Call 911 Now (your child may need an ambulance) If
  • Not moving or very weak
  • Unresponsive or difficult to awaken
  • Difficulty breathing with bluish lips
  • Purple or blood-colored spots or dots on skin
Call Your Doctor Now (night or day) If
  • Your child looks or acts very sick
  • Not alert when awake
  • Any difficulty breathing
  • Great difficulty swallowing fluids or saliva
  • Child is confused (delirious) or has stiff neck or bulging soft spot
  • Had a seizure with the fever
  • Age under 12 weeks with fever above 100.4° F (38.0° C) rectally (Caution: Do not give your baby any fever medicine before being seen)
  • Fever over 104° F (40° C) and not improved 2 hours after fever medicine
  • Very irritable (e.g., inconsolable crying or cries when touched or moved)
  • Won't move an arm or leg normally
  • Signs of dehydration (very dry mouth, no urine in more than 8 hours, etc.).
  • Burning or pain with urination
  • Pain suspected
  • Chronic disease (e.g., sickle cell disease) or medication (e.g., chemotherapy) that causes decreased immunity
  • You think your child needs to be seen urgently
Call Your Doctor Within 24 Hours (between 9 am and 4 pm) If
  • You think your child needs to be seen, but not urgently
  • Age 3-6 months with fever
  • Age 6-24 months with fever present over 24 hours but no other symptoms (e.g., no cold, cough, diarrhea, etc.)
  • Fever repeatedly above 104° F (40° C) despite fever medicine
  • Fever present for more than 3 days
  • Fever returns after gone for over 24 hours
Call Your Doctor During Weekday Office Hours If
  • You have other questions or concerns
Parent Care at Home If
  • Fever with no other symptoms AND you don't think your child needs to be seen

  1. Reassurance: Presence of a fever means your child has an infection, usually caused by a virus. Most fevers are good for sick children and help the body fight infection.  Use the following definitions to help put your child's level of fever into perspective:
    • 100°-102°F (37.8° - 39°C) Low grade fevers: beneficial, desirable range
    • 102°-104°F (39 - 40°C)    Average fever: beneficial
    • Over 104°F (40°C)          High fever: causes discomfort, but harmless
    • Over 106°F (41.1°C)       Very high fever: important to bring it down
    • Over 108°F (42.3°C)       Dangerous fever: fever itself can cause brain damage
  2. Treatment for All Fevers:  Extra Fluids and Less Clothing
    • Give cold fluids orally in unlimited amounts (Reason: good hydration replaces sweat and improves heat loss from the skin).
    • Dress in 1 layer of light weight clothing and sleep with 1 light blanket (avoid bundling).  (Caution: overheated infants can't undress themselves.)
    • For fevers 100°-102° F (37.8° - 39°C), this is the only treatment needed (fever medicines are unnecessary).
  3. Fever Medication:  
    • Fevers only need to be treated with medicine if they cause discomfort. That usually means fevers above 102°F (39°C).
    • Give acetaminophen (e.g., Tylenol) or ibuprofen (e.g., Advil). See the dosage charts.
    • The goal of fever therapy is to bring the temperature down to a comfortable level. Remember, the fever medicine usually lowers the fever by 2° to 3° F (1 - 1.5° C).
    • Avoid aspirin (Reason: risk of Reye's syndrome, a rare but serious brain disease)
    • Avoid alternating acetaminophen and ibuprofen (Reason: unnecessary and risk of overdosage)
  4. Sponging:
    • Note: Sponging is optional for high fevers, not required.
    • Indication: May sponge for (1) fever above 104° F (40° C) AND (2) doesn't come down with acetaminophen (e.g., Tylenol) or ibuprofen (always give fever medicine first).
    • How to sponge: Use lukewarm water (85 - 90° F) (29.4 - 32.2° C). Do not use rubbing alcohol. Sponge for 20-30 minutes.
    • If your child shivers or becomes cold, stop sponging or increase the water temperature.
  5. Contagiousness:  Your child can return to child care or school after the fever is gone and your child feels well enough to participate in normal activities.
  6. Expected Course of Fever:  Most fevers associated with viral illnesses fluctuate between 101° and 104° F (38.4° and 40° C) and last for 2 or 3 days.
  7. Call Your Doctor If:
    • Fever goes above 104° F (40° C) repeatedly
    • Any fever occurs if under 12 weeks old
    • Fever without a cause persists over 24 hours (if age less than 2 years)
    • Fever persists over 3 days (72 hours)
    • Your child becomes worse

And remember, contact your doctor if your child develops any of the "Call Your Doctor" symptoms.

Disclaimer: This information is not intended be a substitute for professional medical advice. It is provided for educational purposes only. You assume full responsibility for how you choose to use this information.

Author and Senior Reviewer: Barton D. Schmitt, M.D.

Last Reviewed: 11/14/2011

Last Revised: 11/14/2011

Content Set: Pediatric HouseCalls Symptom Checker

Copyright 1994-2012 Barton D. Schmitt, M.D.