My Child has a Fever - What should I do?

Definition: If the temperature of your child exceeds the following, they have a fever:
  • Rectal temperature exceeds 38°C (100.4°F)
  • Oral temperature exceeds 37.5°C (99.5°F)
  • Armpit temperature exceeds 37°C (98.6°F)
Children’s armpit temperature is usually around 36.5°C, and fluctuates within the day. Exercise, warm clothes, hot shower or a hot day could all raise their armpit temperature to above 37.5~38°C; hot food or drinks could also raise their oral temperature. If you doubt the higher than usual temperature of your child relates to the factors above, make a measurement again after half an hour. Reason: Fever is a symptom and not an illness or disease; it is our body’s reaction to bacteria, virus and or other infections, a sign that our body’s defence mechanism is fighting these outer enemies. Fever usually results an armpit temperature of 37.3~39.5°C, with an extra 0.5°C for oral temperature and 1°C for rectal temperature. Temperature at this range is not harmful to your child so there’s not too much to worry about. There are many reasons that could cause a fever, mostly seen are bacterial infection, some are virus related. Growing new teeth does not cause fever. Even though most bacterial infection will cure naturally, but it’s still best to consult your family doctor when your child has a fever, in case we missed some infection that require special treatment. How long does fever last? Most bacterial infection caused fever would have an armpit temperature of 37.8 to 39.5°C, and lasting two to three days. Normally speaking, your child’s body temperature does not necessarily correlate to the degree of illness. Instead, what reflects the degree of illness is often how uncomfortable your child looks like (referring to just after when the fever is gone, since during fever everyone feels bad). A fever with armpit temperature of less than 41.2°C does not cause any damage to the brain, so it is false to think that the fever is going to burn/damage the brain; our brain has its own built in temperature regulator mechanism that keeps our brain temperature within a certain range. Even though most children experience fever from time to time, only about 4% of the children will have fever seizure; and normally speaking fever seizure is not harmful to your child, so there’s not too much to worry about.   What can we do besides taking medicine? Warm Bath Usually medication takes effect after 20 minutes, so if your child’s armpit temperature is above 103.1°F (39.5°C), you can give him a warm bath after taking a dose of medicine. Help your child undress and have him sit inside the tube, fill the tube with 84-90°F (29-32°C) degree water (slightly colder than regular shower water temperature) around 5cm in deep, and rinse your child’s body continuously with a towel. If your child shivers, you can either increase the temperature a bit or just stop and wait for the medicine to come in effect. Usually within 10-15 minutes after this bathing, your child’s body temperature will drop slightly, but it’s unlikely to drop below 101.3°F (38.5°C) right away. Avoid applying alcohol product onto your child’s skin, as it’ll quickly cool your child’s skin and causing your child to shiver. Shivering will actually raise body temperature. Dress less During a fever our skin works hard as a heat sink to dissipate our body heat to the surrounding, so it’s important not to over dress during a fever. This is also true for infants. Wear just enough so your child doesn’t shiver.   Lots of Water We lose more water from our skin during a fever, so it’s important to keep up with water intake to prevent dehydration.  Unless for some particular reason that your child is not willing to drink water or the fever is too prolonged, intravenous feeding shouldn’t be needed.   We still recommend consulting your doctor immediately when you observe the following:
  1. Infant is less than 2 months old
  2. Armpit temperature is above 104°F (40°C)
  3. Your child cannot be waken up or wouldn’t stop crying
  4. Experiencing muscle cramp
  5. Your child is not eating or drinking anything
  6. Your child looks seriously ill
  7. Your child tell you that peeing hurts
  8. Your child is having difficulty breathing
Dr. Z